Backports to beta v1.3.6 (#2571 )

* v1.3.6 * Print backtrace on panic (#2535) * Don't activate peers on connect; Test (#2537) * Removing unwarps from sync module (#2551) * Remove unwrap from client module (#2554) * remove unwraps in client * imporve block hash expect message * mining perf trace * Fixed race condition in trace import (#2555)
Update gitlab-ci
2016-10-11 15:53:45 +02:00 · 2016-10-08 10:51:42 +07:00 · 2016-10-08 02:00:06 +02:00 · 2016-10-08 01:02:41 +02:00 · 2016-10-08 00:59:04 +02:00 · 2016-10-07 17:39:41 +02:00
96 changed files with 3370 additions and 1076 deletions
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,7 +1,6 @@
 stages:
  - build
  - test
-  - deploy
 variables:
  GIT_DEPTH: "3"
  SIMPLECOV: "true" 
@@ -18,16 +17,43 @@ linux-stable:
    - tags
    - stable
  script:
-    - export
    - cargo build --release --verbose
    - strip target/release/parity
+    - md5sum target/release/parity >> checksum
+    - aws configure set aws_access_key_id $s3_key 
+    - aws configure set aws_secret_access_key $s3_secret
+    - aws s3api put-object --bucket builds-parity --key $CI_BUILD_REF_NAME/x86_64-unknown-linux-gnu/parity --body target/release/parity
+    - aws s3api put-object --bucket builds-parity --key $CI_BUILD_REF_NAME/x86_64-unknown-linux-gnu/checksum --body checksum
  tags:
    - rust
    - rust-stable
  artifacts:
    paths:
    - target/release/parity
-    name: "${CI_BUILD_NAME}_parity"
+    name: "stable-x86_64-unknown-linux-gnu_parity"
+linux-stable-14.04:
+  stage: build
+  image: ethcore/rust-14.04:latest
+  only:
+    - master
+    - beta
+    - tags
+    - stable
+  script:
+    - cargo build --release --verbose
+    - strip target/release/parity
+    - md5sum target/release/parity >> checksum
+    - aws configure set aws_access_key_id $s3_key 
+    - aws configure set aws_secret_access_key $s3_secret
+    - aws s3api put-object --bucket builds-parity --key $CI_BUILD_REF_NAME/x86_64-unknown-ubuntu_14_04-gnu/parity --body target/release/parity
+    - aws s3api put-object --bucket builds-parity --key $CI_BUILD_REF_NAME/x86_64-unknown-ubuntu_14_04-gnu/checksum --body checksum
+  tags:
+    - rust
+    - rust-14.04
+  artifacts:
+    paths:
+    - target/release/parity
+    name: "stable-x86_64-unknown-ubuntu_14_04-gnu_parity"
 linux-beta:
  stage: build
  image: ethcore/rust:beta
@@ -37,17 +63,16 @@ linux-beta:
    - tags
    - stable
  script:
-    - export
    - cargo build --release --verbose
    - strip target/release/parity
-    - cp target/release/parity parity
  tags:
    - rust
    - rust-beta
  artifacts:
    paths:
    - target/release/parity
-    name: "${CI_BUILD_NAME}_parity"
+    name: "beta-x86_64-unknown-linux-gnu_parity"
+  allow_failure: true
 linux-nightly:
  stage: build
  image: ethcore/rust:nightly
@@ -65,7 +90,7 @@ linux-nightly:
  artifacts:
    paths:
    - target/release/parity
-    name: "${CI_BUILD_NAME}_parity"
+    name: "nigthly-x86_64-unknown-linux-gnu_parity"
  allow_failure: true
 linux-centos:
  stage: build
@@ -80,13 +105,18 @@ linux-centos:
    - export CC="gcc"
    - cargo build --release --verbose
    - strip target/release/parity
+    - md5sum target/release/parity >> checksum
+    - aws configure set aws_access_key_id $s3_key 
+    - aws configure set aws_secret_access_key $s3_secret
+    - aws s3api put-object --bucket builds-parity --key $CI_BUILD_REF_NAME/x86_64-unknown-centos-gnu/parity --body target/release/parity
+    - aws s3api put-object --bucket builds-parity --key $CI_BUILD_REF_NAME/x86_64-unknown-centos-gnu/checksum --body checksum
  tags:
    - rust
    - rust-centos
  artifacts:
    paths:
    - target/release/parity
-    name: "${CI_BUILD_NAME}_parity"
+    name: "x86_64-unknown-centos-gnu_parity"
 linux-armv7:
  stage: build
  image: ethcore/rust-armv7:latest
@@ -96,7 +126,6 @@ linux-armv7:
    - tags
    - stable
  script:
-    - export
    - rm -rf .cargo
    - mkdir -p .cargo
    - echo "[target.armv7-unknown-linux-gnueabihf]" >> .cargo/config
@@ -104,13 +133,18 @@ linux-armv7:
    - cat .cargo/config
    - cargo build --target armv7-unknown-linux-gnueabihf --release --verbose
    - arm-linux-gnueabihf-strip target/armv7-unknown-linux-gnueabihf/release/parity
+    - md5sum target/armv7-unknown-linux-gnueabihf/release/parity >> checksum
+    - aws configure set aws_access_key_id $s3_key 
+    - aws configure set aws_secret_access_key $s3_secret
+    - aws s3api put-object --bucket builds-parity --key $CI_BUILD_REF_NAME/armv7-unknown-linux-gnueabihf/parity --body target/armv7-unknown-linux-gnueabihf/release/parity
+    - aws s3api put-object --bucket builds-parity --key $CI_BUILD_REF_NAME/armv7-unknown-linux-gnueabihf/checksum --body checksum
  tags:
    - rust
    - rust-arm
  artifacts:
    paths:
    - target/armv7-unknown-linux-gnueabihf/release/parity
-    name: "${CI_BUILD_NAME}_parity"
+    name: "armv7_unknown_linux_gnueabihf_parity"
  allow_failure: true
 linux-arm:
  stage: build
@@ -121,7 +155,6 @@ linux-arm:
    - tags
    - stable
  script:
-    - export
    - rm -rf .cargo
    - mkdir -p .cargo
    - echo "[target.arm-unknown-linux-gnueabihf]" >> .cargo/config
@@ -129,13 +162,18 @@ linux-arm:
    - cat .cargo/config
    - cargo build --target arm-unknown-linux-gnueabihf --release --verbose
    - arm-linux-gnueabihf-strip target/arm-unknown-linux-gnueabihf/release/parity
+    - md5sum target/arm-unknown-linux-gnueabihf/release/parity >> checksum
+    - aws configure set aws_access_key_id $s3_key 
+    - aws configure set aws_secret_access_key $s3_secret
+    - aws s3api put-object --bucket builds-parity --key $CI_BUILD_REF_NAME/arm-unknown-linux-gnueabihf/parity --body target/arm-unknown-linux-gnueabihf/release/parity
+    - aws s3api put-object --bucket builds-parity --key $CI_BUILD_REF_NAME/arm-unknown-linux-gnueabihf/checksum --body checksum
  tags:
    - rust
    - rust-arm
  artifacts:
    paths:
    - target/arm-unknown-linux-gnueabihf/release/parity
-    name: "${CI_BUILD_NAME}_parity"
+    name: "arm-unknown-linux-gnueabihf_parity"
  allow_failure: true
 linux-armv6:
  stage: build
@@ -146,7 +184,6 @@ linux-armv6:
    - tags
    - stable
  script:
-    - export
    - rm -rf .cargo
    - mkdir -p .cargo
    - echo "[target.arm-unknown-linux-gnueabi]" >> .cargo/config
@@ -154,13 +191,18 @@ linux-armv6:
    - cat .cargo/config
    - cargo build --target arm-unknown-linux-gnueabi --release --verbose
    - arm-linux-gnueabi-strip target/arm-unknown-linux-gnueabi/release/parity
+    - md5sum target/arm-unknown-linux-gnueabi/release/parity >> checksum 
+    - aws configure set aws_access_key_id $s3_key 
+    - aws configure set aws_secret_access_key $s3_secret
+    - aws s3api put-object --bucket builds-parity --key $CI_BUILD_REF_NAME/arm-unknown-linux-gnueabi/parity --body target/arm-unknown-linux-gnueabi/release/parity
+    - aws s3api put-object --bucket builds-parity --key $CI_BUILD_REF_NAME/arm-unknown-linux-gnueabi/checksum --body checksum
  tags:
    - rust
    - rust-arm
  artifacts:
    paths:
    - target/arm-unknown-linux-gnueabi/release/parity
-    name: "${CI_BUILD_NAME}_parity"
+    name: "arm-unknown-linux-gnueabi_parity"
  allow_failure: true
 linux-aarch64:
  stage: build
@@ -171,7 +213,6 @@ linux-aarch64:
    - tags
    - stable
  script:
-    - export
    - rm -rf .cargo
    - mkdir -p .cargo
    - echo "[target.aarch64-unknown-linux-gnu]" >> .cargo/config
@@ -179,13 +220,18 @@ linux-aarch64:
    - cat .cargo/config
    - cargo build --target aarch64-unknown-linux-gnu --release --verbose
    - aarch64-linux-gnu-strip target/aarch64-unknown-linux-gnu/release/parity
+    - md5sum target/aarch64-unknown-linux-gnu/release/parity >> checksum
+    - aws configure set aws_access_key_id $s3_key 
+    - aws configure set aws_secret_access_key $s3_secret
+    - aws s3api put-object --bucket builds-parity --key $CI_BUILD_REF_NAME/aarch64-unknown-linux-gnu/parity --body target/aarch64-unknown-linux-gnu/release/parity
+    - aws s3api put-object --bucket builds-parity --key $CI_BUILD_REF_NAME/aarch64-unknown-linux-gnu/checksum --body checksum
  tags:
    - rust
    - rust-arm
  artifacts:
    paths:
    - target/aarch64-unknown-linux-gnu/release/parity
-    name: "${CI_BUILD_NAME}_parity"
+    name: "aarch64-unknown-linux-gnu_parity"
  allow_failure: true
 darwin:
  stage: build
@@ -196,12 +242,17 @@ darwin:
    - stable
  script:
    - cargo build --release --verbose
+    - md5sum target/release/parity >> checksum
+    - aws configure set aws_access_key_id $s3_key 
+    - aws configure set aws_secret_access_key $s3_secret
+    - aws s3api put-object --bucket builds-parity --key $CI_BUILD_REF_NAME/x86_64-apple-darwin/parity --body target/release/parity
+    - aws s3api put-object --bucket builds-parity --key $CI_BUILD_REF_NAME/x86_64-apple-darwin/checksum --body checksum
  tags:
    - osx
  artifacts:
    paths:
    - target/release/parity
-    name: "${CI_BUILD_NAME}_parity"
+    name: "x86_64-apple-darwin_parity"
 windows:
  stage: build
  only:
@@ -213,31 +264,30 @@ windows:
    - set INCLUDE=C:\Program Files (x86)\Microsoft SDKs\Windows\v7.1A\Include;C:\vs2015\VC\include;C:\Program Files (x86)\Windows Kits\10\Include\10.0.10240.0\ucrt
    - set LIB=C:\vs2015\VC\lib;C:\Program Files (x86)\Windows Kits\10\Lib\10.0.10240.0\ucrt\x64
    - set RUST_BACKTRACE=1
+    - set RUSTFLAGS=-Zorbit=off
    - rustup default stable-x86_64-pc-windows-msvc
    - cargo build --release --verbose
+    - cmd md5sum target\release\parity >> checksum
+    - aws configure set aws_access_key_id %s3_key%
+    - aws configure set aws_secret_access_key %s3_secret%
+    - aws s3api put-object --bucket builds-parity --key %CI_BUILD_REF_NAME%/x86_64-pc-windows-msvc/parity --body target\release\parity.exe
+    - aws s3api put-object --bucket builds-parity --key %CI_BUILD_REF_NAME%/x86_64-pc-windows-msvc/parity --body target\release\parity.pdb
+    - aws s3api put-object --bucket builds-parity --key %CI_BUILD_REF_NAME%/x86_64-pc-windows-msvc/checksum --body checksum
  tags:
   - rust-windows
  artifacts:
    paths:
    - target/release/parity.exe
    - target/release/parity.pdb
-    name: "${CI_BUILD_NAME}_parity"
+    name: "x86_64-pc-windows-msvc_parity"
 test-linux:
  stage: test
  before_script:
    - git submodule update --init --recursive
  script:
+    - export RUST_BACKTRACE=1
    - ./test.sh --verbose
  tags:
    - rust-test
  dependencies:
    - linux-stable
-deploy-binaries:
-  stage: deploy
-  only:
-    - master
-    - beta
-    - tags
-    - stable
-  script:
-    - ll
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,12 +1,12 @@
 [root]
 name = "parity"
-version = "1.3.1"
+version = "1.3.6"
 dependencies = [
 "ansi_term 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
 "clippy 0.0.80 (registry+https://github.com/rust-lang/crates.io-index)",
 "ctrlc 1.1.1 (git+https://github.com/ethcore/rust-ctrlc.git)",
- "daemonize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "docopt 0.6.80 (registry+https://github.com/rust-lang/crates.io-index)",
+ "daemonize 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "docopt 0.6.86 (registry+https://github.com/rust-lang/crates.io-index)",
 "env_logger 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
 "ethcore 1.3.0",
 "ethcore-dapps 1.3.0",
@@ -20,22 +20,22 @@ dependencies = [
 "ethcore-logger 1.3.0",
 "ethcore-rpc 1.3.0",
 "ethcore-signer 1.3.0",
- "ethcore-util 1.3.1",
+ "ethcore-util 1.3.6",
 "ethsync 1.3.0",
 "fdlimit 0.1.0",
 "hyper 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "isatty 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "json-ipc-server 0.2.4 (git+https://github.com/ethcore/json-ipc-server.git)",
+ "json-ipc-server 0.2.4 (git+https://github.com/ethcore/json-ipc-server.git?branch=beta)",
 "lazy_static 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
 "num_cpus 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
- "number_prefix 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "number_prefix 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
 "regex 0.1.68 (registry+https://github.com/rust-lang/crates.io-index)",
- "rpassword 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rpassword 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
 "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
 "rustc_version 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
 "semver 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "syntex 0.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syntex 0.36.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "time 0.1.35 (registry+https://github.com/rust-lang/crates.io-index)",
 "winapi 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -112,6 +112,20 @@ name = "bloomchain"
 version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"

+[[package]]
+name = "bloomfilter"
+version = "0.0.10"
+source = "git+https://github.com/ethcore/rust-bloom-filter#e66a3f20443bc78810877390ad4da00ebdf74d78"
+dependencies = [
+ "bit-vec 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "byteorder"
+version = "0.5.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "bytes"
 version = "0.3.0"
@@ -178,7 +192,7 @@ dependencies = [

 [[package]]
 name = "daemonize"
-version = "0.2.2"
+version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "libc 0.2.12 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -194,12 +208,13 @@ dependencies = [

 [[package]]
 name = "docopt"
-version = "0.6.80"
+version = "0.6.86"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
+ "lazy_static 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "regex 0.1.68 (registry+https://github.com/rust-lang/crates.io-index)",
 "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
- "strsim 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "strsim 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]

 [[package]]
@@ -222,7 +237,7 @@ version = "0.5.4"
 source = "git+https://github.com/ethcore/rust-secp256k1#a9a0b1be1f39560ca86e8fc8e55e205a753ff25c"
 dependencies = [
 "arrayvec 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "gcc 0.3.28 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gcc 0.3.35 (registry+https://github.com/rust-lang/crates.io-index)",
 "libc 0.2.12 (registry+https://github.com/rust-lang/crates.io-index)",
 "rand 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
 "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -244,6 +259,8 @@ version = "1.3.0"
 dependencies = [
 "bit-set 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "bloomchain 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "bloomfilter 0.0.10 (git+https://github.com/ethcore/rust-bloom-filter)",
+ "byteorder 0.5.3 (registry+https://github.com/rust-lang/crates.io-index)",
 "clippy 0.0.80 (registry+https://github.com/rust-lang/crates.io-index)",
 "crossbeam 0.2.9 (registry+https://github.com/rust-lang/crates.io-index)",
 "env_logger 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -253,16 +270,18 @@ dependencies = [
 "ethcore-ipc 1.3.0",
 "ethcore-ipc-codegen 1.3.0",
 "ethcore-ipc-nano 1.3.0",
- "ethcore-util 1.3.1",
+ "ethcore-util 1.3.6",
 "ethjson 0.1.0",
 "ethstore 0.1.0",
+ "evmjit 1.3.0",
 "heapsize 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
 "hyper 0.9.4 (git+https://github.com/ethcore/hyper)",
 "lazy_static 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lru-cache 0.0.7 (registry+https://github.com/rust-lang/crates.io-index)",
 "num_cpus 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
 "rand 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
- "rayon 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rayon 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
 "rust-crypto 0.2.36 (registry+https://github.com/rust-lang/crates.io-index)",
 "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
 "semver 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -275,7 +294,7 @@ version = "1.3.0"
 dependencies = [
 "clippy 0.0.80 (registry+https://github.com/rust-lang/crates.io-index)",
 "ethcore-rpc 1.3.0",
- "ethcore-util 1.3.1",
+ "ethcore-util 1.3.6",
 "hyper 0.9.4 (git+https://github.com/ethcore/hyper)",
 "jsonrpc-core 2.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "jsonrpc-http-server 6.1.0 (git+https://github.com/ethcore/jsonrpc-http-server.git)",
@@ -317,7 +336,7 @@ name = "ethcore-ipc"
 version = "1.3.0"
 dependencies = [
 "ethcore-devtools 1.3.0",
- "ethcore-util 1.3.1",
+ "ethcore-util 1.3.6",
 "nanomsg 0.5.1 (git+https://github.com/ethcore/nanomsg.rs.git)",
 "semver 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -362,7 +381,7 @@ dependencies = [
 "ethcore-ipc 1.3.0",
 "ethcore-ipc-codegen 1.3.0",
 "ethcore-ipc-nano 1.3.0",
- "ethcore-util 1.3.1",
+ "ethcore-util 1.3.6",
 "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
 "nanomsg 0.5.1 (git+https://github.com/ethcore/nanomsg.rs.git)",
 "semver 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -374,7 +393,7 @@ name = "ethcore-logger"
 version = "1.3.0"
 dependencies = [
 "env_logger 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "ethcore-util 1.3.1",
+ "ethcore-util 1.3.6",
 "isatty 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "lazy_static 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -389,7 +408,7 @@ dependencies = [
 "ansi_term 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
 "ethcore-devtools 1.3.0",
 "ethcore-io 1.3.0",
- "ethcore-util 1.3.1",
+ "ethcore-util 1.3.6",
 "igd 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "libc 0.2.12 (registry+https://github.com/rust-lang/crates.io-index)",
 "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -413,10 +432,10 @@ dependencies = [
 "ethcore-devtools 1.3.0",
 "ethcore-io 1.3.0",
 "ethcore-ipc 1.3.0",
- "ethcore-util 1.3.1",
+ "ethcore-util 1.3.6",
 "ethjson 0.1.0",
 "ethsync 1.3.0",
- "json-ipc-server 0.2.4 (git+https://github.com/ethcore/json-ipc-server.git)",
+ "json-ipc-server 0.2.4 (git+https://github.com/ethcore/json-ipc-server.git?branch=beta)",
 "jsonrpc-core 2.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "jsonrpc-http-server 6.1.0 (git+https://github.com/ethcore/jsonrpc-http-server.git)",
 "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -436,7 +455,7 @@ dependencies = [
 "env_logger 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
 "ethcore-io 1.3.0",
 "ethcore-rpc 1.3.0",
- "ethcore-util 1.3.1",
+ "ethcore-util 1.3.6",
 "jsonrpc-core 2.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
 "parity-dapps-signer 1.4.0 (git+https://github.com/ethcore/parity-ui.git)",
@@ -447,7 +466,7 @@ dependencies = [

 [[package]]
 name = "ethcore-util"
-version = "1.3.1"
+version = "1.3.6"
 dependencies = [
 "ansi_term 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
 "arrayvec 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -480,7 +499,7 @@ dependencies = [
 name = "ethjson"
 version = "0.1.0"
 dependencies = [
- "ethcore-util 1.3.1",
+ "ethcore-util 1.3.6",
 "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
 "serde 0.7.9 (registry+https://github.com/rust-lang/crates.io-index)",
 "serde_codegen 0.7.9 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -528,7 +547,7 @@ dependencies = [
 "ethcore-ipc-codegen 1.3.0",
 "ethcore-ipc-nano 1.3.0",
 "ethcore-network 1.3.0",
- "ethcore-util 1.3.1",
+ "ethcore-util 1.3.6",
 "heapsize 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
 "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
 "parking_lot 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -537,6 +556,13 @@ dependencies = [
 "time 0.1.35 (registry+https://github.com/rust-lang/crates.io-index)",
 ]

+[[package]]
+name = "evmjit"
+version = "1.3.0"
+dependencies = [
+ "tiny-keccak 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "fdlimit"
 version = "0.1.0"
@@ -546,8 +572,11 @@ dependencies = [

 [[package]]
 name = "gcc"
-version = "0.3.28"
+version = "0.3.35"
 source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rayon 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
+]

 [[package]]
 name = "glob"
@@ -681,7 +710,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
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 version = "0.2.4"
-source = "git+https://github.com/ethcore/json-ipc-server.git#56b6307130710ebc73cb9be087b6ed0b6c400bcf"
+source = "git+https://github.com/ethcore/json-ipc-server.git?branch=beta#42d0dacc9cd203757ba894d7ba3690e12ef9f934"
 dependencies = [
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@@ -738,11 +767,24 @@ name = "libc"
 version = "0.2.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"

+[[package]]
+name = "linked-hash-map"
+version = "0.0.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
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 version = "0.3.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"

+[[package]]
+name = "lru-cache"
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "linked-hash-map 0.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "matches"
 version = "0.1.2"
@@ -847,7 +889,7 @@ name = "nanomsg-sys"
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 source = "git+https://github.com/ethcore/nanomsg.rs.git#c40fe442c9afaea5b38009a3d992ca044dcceb00"
 dependencies = [
- "gcc 0.3.28 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gcc 0.3.35 (registry+https://github.com/rust-lang/crates.io-index)",
 "libc 0.2.12 (registry+https://github.com/rust-lang/crates.io-index)",
 ]

@@ -974,7 +1016,7 @@ dependencies = [

 [[package]]
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-version = "0.2.5"
+version = "0.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
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@@ -1155,7 +1197,7 @@ dependencies = [

 [[package]]
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-version = "0.3.1"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
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@@ -1183,7 +1225,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
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 version = "0.4.5"
-source = "git+https://github.com/ethcore/rust-rocksdb#485dd747a2c9a9f910fc8ac696fc9edf5fa22aa3"
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 dependencies = [
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@@ -1192,9 +1234,9 @@ dependencies = [
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 version = "0.3.0"
-source = "git+https://github.com/ethcore/rust-rocksdb#485dd747a2c9a9f910fc8ac696fc9edf5fa22aa3"
+source = "git+https://github.com/ethcore/rust-rocksdb#ffc7c82380fe8569f85ae6743f7f620af2d4a679"
 dependencies = [
- "gcc 0.3.28 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gcc 0.3.35 (registry+https://github.com/rust-lang/crates.io-index)",
 "libc 0.2.12 (registry+https://github.com/rust-lang/crates.io-index)",
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@@ -1211,7 +1253,7 @@ dependencies = [

 [[package]]
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-version = "0.2.2"
+version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
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@@ -1225,7 +1267,7 @@ name = "rust-crypto"
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 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "gcc 0.3.28 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gcc 0.3.35 (registry+https://github.com/rust-lang/crates.io-index)",
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@@ -1293,7 +1335,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 name = "sha3"
 version = "0.1.0"
 dependencies = [
- "gcc 0.3.28 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gcc 0.3.35 (registry+https://github.com/rust-lang/crates.io-index)",
 ]

 [[package]]
@@ -1337,7 +1379,7 @@ source = "git+https://github.com/carllerche/stable-heap?rev=3c5cd1ca47#3c5cd1ca4

 [[package]]
 name = "strsim"
-version = "0.3.0"
+version = "0.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"

 [[package]]
@@ -1348,6 +1390,14 @@ dependencies = [
 "syntex_syntax 0.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]

+[[package]]
+name = "syntex"
+version = "0.36.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "syntex_syntax 0.36.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "syntex_syntax"
 version = "0.33.0"
@@ -1361,6 +1411,19 @@ dependencies = [
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 ]

+[[package]]
+name = "syntex_syntax"
+version = "0.36.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "bitflags 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.12 (registry+https://github.com/rust-lang/crates.io-index)",
+ "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
+ "term 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)",
+ "unicode-xid 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "table"
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@@ -1593,6 +1656,8 @@ dependencies = [
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@@ -1601,13 +1666,13 @@ dependencies = [
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@@ -1620,14 +1685,16 @@ dependencies = [
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@@ -1673,13 +1740,13 @@ dependencies = [
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 "checksum syntex 0.33.0 (registry+https://github.com/rust-lang/crates.io-index)" = "393b6dd0889df2b064beeea954cfda6bc2571604ac460deeae0fed55a53988af"
+"checksum syntex 0.36.0 (registry+https://github.com/rust-lang/crates.io-index)" = "61dc0bbe1e46dcd53ec50d6600e750152c22e0e9352cadbd413e86fb847ae899"
 "checksum syntex_syntax 0.33.0 (registry+https://github.com/rust-lang/crates.io-index)" = "44bded3cabafc65c90b663b1071bd2d198a9ab7515e6ce729e4570aaf53c407e"
+"checksum syntex_syntax 0.36.0 (registry+https://github.com/rust-lang/crates.io-index)" = "2b92a8c33fad2fa99e14fe499ec17e82b6c6496a7a38a499f33b584ffa1886fa"
 "checksum target_info 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c63f48baada5c52e65a29eef93ab4f8982681b67f9e8d29c7b05abcfec2b9ffe"
 "checksum term 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)" = "f2077e54d38055cf1ca0fd7933a2e00cd3ec8f6fed352b2a377f06dcdaaf3281"
 "checksum termios 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "d5d9cf598a6d7ce700a4e6a9199da127e6819a61e64b68609683cc9a01b5683a"
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 description = "Ethcore client."
 name = "parity"
-version = "1.3.1"
+version = "1.3.6"
 license = "GPL-3.0"
 authors = ["Ethcore <admin@ethcore.io>"]
 build = "build.rs"
@@ -39,7 +39,7 @@ ethcore-ipc-nano = { path = "ipc/nano" }
 ethcore-ipc = { path = "ipc/rpc" }
 ethcore-ipc-hypervisor = { path = "ipc/hypervisor" }
 ethcore-logger = { path = "logger" }
-json-ipc-server = { git = "https://github.com/ethcore/json-ipc-server.git" }
+json-ipc-server = { git = "https://github.com/ethcore/json-ipc-server.git", branch = "beta" }
 ethcore-dapps = { path = "dapps", optional = true }
 clippy = { version = "0.0.80", optional = true}

@@ -59,6 +59,7 @@ ui = ["dapps", "ethcore-signer/ui"]
 use-precompiled-js = ["ethcore-dapps/use-precompiled-js", "ethcore-signer/use-precompiled-js"]
 dapps = ["ethcore-dapps"]
 ipc = ["ethcore/ipc"]
+jit = ["ethcore/jit"]
 dev = ["clippy", "ethcore/dev", "ethcore-util/dev", "ethsync/dev", "ethcore-rpc/dev", "ethcore-dapps/dev", "ethcore-signer/dev"]
 json-tests = ["ethcore/json-tests"]

@@ -67,6 +68,6 @@ path = "parity/main.rs"
 name = "parity"

 [profile.release]
-debug = true
+debug = false
 lto = false

--- a/appveyor.yml
+++ b/appveyor.yml
@@ -6,6 +6,7 @@ environment:
  certpass:
    secure: 0BgXJqxq9Ei34/hZ7121FQ==
  keyfile: C:\users\appveyor\Certificates.p12
+  RUSTFLAGS: -Zorbit=off

 branches:
  only:
@@ -18,10 +19,10 @@ branches:
 install:
  - git submodule update --init --recursive
  - ps: Install-Product node 6
-  - ps: Start-FileDownload "https://static.rust-lang.org/dist/rust-1.10.0-x86_64-pc-windows-msvc.exe"
+  - ps: Start-FileDownload "https://static.rust-lang.org/dist/rust-1.12.0-x86_64-pc-windows-msvc.exe"
  - ps: Start-FileDownload "https://github.com/ethcore/win-build/raw/master/SimpleFC.dll" -FileName nsis\SimpleFC.dll
  - ps: Start-FileDownload "https://github.com/ethcore/win-build/raw/master/vc_redist.x64.exe" -FileName nsis\vc_redist.x64.exe
-  - rust-1.10.0-x86_64-pc-windows-msvc.exe /VERYSILENT /NORESTART /DIR="C:\Program Files (x86)\Rust"
+  - rust-1.12.0-x86_64-pc-windows-msvc.exe /VERYSILENT /NORESTART /DIR="C:\Program Files (x86)\Rust"
  - SET PATH=%PATH%;C:\Program Files (x86)\Rust\bin;C:\Program Files (x86)\NSIS;C:\Program Files (x86)\Microsoft SDKs\Windows\v7.1A\Bin
  - rustc -V
  - cargo -V
--- a/docker/ubuntu-aarch64/Dockerfile
+++ b/docker/ubuntu-aarch64/Dockerfile
@@ -23,15 +23,9 @@ RUN rustup target add aarch64-unknown-linux-gnu
 # show backtraces
 ENV RUST_BACKTRACE 1

-# set compilers
-ENV CXX aarch64-linux-gnu-g++
-ENV CC aarch64-linux-gnu-gcc
-
 # show tools
 RUN rustc -vV && \
- cargo -V && \
- gcc -v &&\
- g++ -v
+ cargo -V 

 # build parity
 RUN git clone https://github.com/ethcore/parity && \
--- a/docker/ubuntu-arm/Dockerfile
+++ b/docker/ubuntu-arm/Dockerfile
@@ -23,15 +23,9 @@ RUN rustup target add armv7-unknown-linux-gnueabihf
 # show backtraces
 ENV RUST_BACKTRACE 1

-# set compilers
-ENV CXX arm-linux-gnueabihf-g++
-ENV CC arm-linux-gnueabihf-gcc
-
 # show tools
 RUN rustc -vV && \
- cargo -V && \
- gcc -v &&\
- g++ -v
+ cargo -V

 # build parity
 RUN git clone https://github.com/ethcore/parity && \
--- a/ethcore/Cargo.toml
+++ b/ethcore/Cargo.toml
@@ -20,7 +20,7 @@ num_cpus = "0.2"
 crossbeam = "0.2.9"
 lazy_static = "0.2"
 bloomchain = "0.1"
-rayon = "0.3.1"
+rayon = "0.4"
 semver = "0.2"
 bit-set = "0.4"
 time = "0.1"
@@ -35,6 +35,9 @@ ethcore-ipc = { path = "../ipc/rpc" }
 ethstore = { path = "../ethstore" }
 ethcore-ipc-nano = { path = "../ipc/nano" }
 rand = "0.3"
+lru-cache = "0.0.7"
+bloomfilter = { git = "https://github.com/ethcore/rust-bloom-filter" }
+byteorder = "0.5"

 [dependencies.hyper]
 git = "https://github.com/ethcore/hyper"
--- a/ethcore/src/account.rs
+++ b/ethcore/src/account.rs
@@ -16,15 +16,18 @@

 //! Single account in the system.

-use std::collections::hash_map::Entry;
 use util::*;
 use pod_account::*;
 use account_db::*;
+use lru_cache::LruCache;

-use std::cell::{Ref, RefCell, Cell};
+use std::cell::{RefCell, Cell};
+
+const STORAGE_CACHE_ITEMS: usize = 8192;

 /// Single account in the system.
-#[derive(Clone)]
+/// Keeps track of changes to the code and storage.
+/// The changes are applied in `commit_storage` and `commit_code`
 pub struct Account {
 	// Balance of the account.
 	balance: U256,
@@ -32,14 +35,20 @@ pub struct Account {
 	nonce: U256,
 	// Trie-backed storage.
 	storage_root: H256,
-	// Overlay on trie-backed storage - tuple is (<clean>, <value>).
-	storage_overlay: RefCell<HashMap<H256, (Filth, H256)>>,
-	// Code hash of the account. If None, means that it's a contract whose code has not yet been set.
-	code_hash: Option<H256>,
+	// LRU Cache of the trie-backed storage.
+	// This is limited to `STORAGE_CACHE_ITEMS` recent queries
+	storage_cache: RefCell<LruCache<H256, H256>>,
+	// Modified storage. Accumulates changes to storage made in `set_storage`
+	// Takes precedence over `storage_cache`.
+	storage_changes: HashMap<H256, H256>,
+	// Code hash of the account.
+	code_hash: H256,
+	// Size of the accoun code.
+	code_size: Option<u64>,
 	// Code cache of the account.
-	code_cache: Bytes,
-	// Account is new or has been modified
-	filth: Filth,
+	code_cache: Arc<Bytes>,
+	// Account code new or has been modified.
+	code_filth: Filth,
 	// Cached address hash.
 	address_hash: Cell<Option<H256>>,
 }
@@ -52,24 +61,32 @@ impl Account {
 			balance: balance,
 			nonce: nonce,
 			storage_root: SHA3_NULL_RLP,
-			storage_overlay: RefCell::new(storage.into_iter().map(|(k, v)| (k, (Filth::Dirty, v))).collect()),
-			code_hash: Some(code.sha3()),
-			code_cache: code,
-			filth: Filth::Dirty,
+			storage_cache: Self::empty_storage_cache(),
+			storage_changes: storage,
+			code_hash: code.sha3(),
+			code_size: Some(code.len() as u64),
+			code_cache: Arc::new(code),
+			code_filth: Filth::Dirty,
 			address_hash: Cell::new(None),
 		}
 	}

+	fn empty_storage_cache() -> RefCell<LruCache<H256, H256>> {
+		RefCell::new(LruCache::new(STORAGE_CACHE_ITEMS))
+	}
+
 	/// General constructor.
 	pub fn from_pod(pod: PodAccount) -> Account {
 		Account {
 			balance: pod.balance,
 			nonce: pod.nonce,
 			storage_root: SHA3_NULL_RLP,
-			storage_overlay: RefCell::new(pod.storage.into_iter().map(|(k, v)| (k, (Filth::Dirty, v))).collect()),
-			code_hash: pod.code.as_ref().map(|c| c.sha3()),
-			code_cache: pod.code.as_ref().map_or_else(|| { warn!("POD account with unknown code is being created! Assuming no code."); vec![] }, |c| c.clone()),
-			filth: Filth::Dirty,
+			storage_cache: Self::empty_storage_cache(),
+			storage_changes: pod.storage.into_iter().collect(),
+			code_hash: pod.code.as_ref().map_or(SHA3_EMPTY, |c| c.sha3()),
+			code_filth: Filth::Dirty,
+			code_size: Some(pod.code.as_ref().map_or(0, |c| c.len() as u64)),
+			code_cache: Arc::new(pod.code.map_or_else(|| { warn!("POD account with unknown code is being created! Assuming no code."); vec![] }, |c| c)),
 			address_hash: Cell::new(None),
 		}
 	}
@@ -80,10 +97,12 @@ impl Account {
 			balance: balance,
 			nonce: nonce,
 			storage_root: SHA3_NULL_RLP,
-			storage_overlay: RefCell::new(HashMap::new()),
-			code_hash: Some(SHA3_EMPTY),
-			code_cache: vec![],
-			filth: Filth::Dirty,
+			storage_cache: Self::empty_storage_cache(),
+			storage_changes: HashMap::new(),
+			code_hash: SHA3_EMPTY,
+			code_cache: Arc::new(vec![]),
+			code_size: Some(0),
+			code_filth: Filth::Clean,
 			address_hash: Cell::new(None),
 		}
 	}
@@ -95,10 +114,12 @@ impl Account {
 			nonce: r.val_at(0),
 			balance: r.val_at(1),
 			storage_root: r.val_at(2),
-			storage_overlay: RefCell::new(HashMap::new()),
-			code_hash: Some(r.val_at(3)),
-			code_cache: vec![],
-			filth: Filth::Clean,
+			storage_cache: Self::empty_storage_cache(),
+			storage_changes: HashMap::new(),
+			code_hash: r.val_at(3),
+			code_cache: Arc::new(vec![]),
+			code_size: None,
+			code_filth: Filth::Clean,
 			address_hash: Cell::new(None),
 		}
 	}
@@ -110,10 +131,12 @@ impl Account {
 			balance: balance,
 			nonce: nonce,
 			storage_root: SHA3_NULL_RLP,
-			storage_overlay: RefCell::new(HashMap::new()),
-			code_hash: None,
-			code_cache: vec![],
-			filth: Filth::Dirty,
+			storage_cache: Self::empty_storage_cache(),
+			storage_changes: HashMap::new(),
+			code_hash: SHA3_EMPTY,
+			code_cache: Arc::new(vec![]),
+			code_size: None,
+			code_filth: Filth::Clean,
 			address_hash: Cell::new(None),
 		}
 	}
@@ -121,46 +144,52 @@ impl Account {
 	/// Set this account's code to the given code.
 	/// NOTE: Account should have been created with `new_contract()`
 	pub fn init_code(&mut self, code: Bytes) {
-		assert!(self.code_hash.is_none());
-		self.code_cache = code;
-		self.filth = Filth::Dirty;
+		self.code_hash = code.sha3();
+		self.code_cache = Arc::new(code);
+		self.code_size = Some(self.code_cache.len() as u64);
+		self.code_filth = Filth::Dirty;
 	}

 	/// Reset this account's code to the given code.
 	pub fn reset_code(&mut self, code: Bytes) {
-		self.code_hash = None;
 		self.init_code(code);
 	}

 	/// Set (and cache) the contents of the trie's storage at `key` to `value`.
 	pub fn set_storage(&mut self, key: H256, value: H256) {
-		match self.storage_overlay.borrow_mut().entry(key) {
-			Entry::Occupied(ref mut entry) if entry.get().1 != value => {
-				entry.insert((Filth::Dirty, value));
-				self.filth = Filth::Dirty;
-			},
-			Entry::Vacant(entry) => {
-				entry.insert((Filth::Dirty, value));
-				self.filth = Filth::Dirty;
-			},
-			_ => (),
-		}
+		self.storage_changes.insert(key, value);
 	}

 	/// Get (and cache) the contents of the trie's storage at `key`.
+	/// Takes modifed storage into account.
 	pub fn storage_at(&self, db: &AccountDB, key: &H256) -> H256 {
-		self.storage_overlay.borrow_mut().entry(key.clone()).or_insert_with(||{
-			let db = SecTrieDB::new(db, &self.storage_root)
-				.expect("Account storage_root initially set to zero (valid) and only altered by SecTrieDBMut. \
-				SecTrieDBMut would not set it to an invalid state root. Therefore the root is valid and DB creation \
-				using it will not fail.");
+		if let Some(value) = self.cached_storage_at(key) {
+			return value;
+		}
+		let db = SecTrieDB::new(db, &self.storage_root)
+			.expect("Account storage_root initially set to zero (valid) and only altered by SecTrieDBMut. \
+			SecTrieDBMut would not set it to an invalid state root. Therefore the root is valid and DB creation \
+			using it will not fail.");

-			let item: U256 = match db.get(key){
-				Ok(x) => x.map_or_else(U256::zero, decode),
-				Err(e) => panic!("Encountered potential DB corruption: {}", e),
-			};
-			(Filth::Clean, item.into())
-		}).1.clone()
+		let item: U256 = match db.get(key){
+			Ok(x) => x.map_or_else(U256::zero, decode),
+			Err(e) => panic!("Encountered potential DB corruption: {}", e),
+		};
+		let value: H256 = item.into();
+		self.storage_cache.borrow_mut().insert(key.clone(), value.clone());
+		value
+	}
+
+	/// Get cached storage value if any. Returns `None` if the
+	/// key is not in the cache.
+	pub fn cached_storage_at(&self, key: &H256) -> Option<H256> {
+		if let Some(value) = self.storage_changes.get(key) {
+			return Some(value.clone())
+		}
+		if let Some(value) = self.storage_cache.borrow_mut().get_mut(key) {
+			return Some(value.clone())
+		}
+		None
 	}

 	/// return the balance associated with this account.
@@ -169,10 +198,9 @@ impl Account {
 	/// return the nonce associated with this account.
 	pub fn nonce(&self) -> &U256 { &self.nonce }

-	#[cfg(test)]
 	/// return the code hash associated with this account.
 	pub fn code_hash(&self) -> H256 {
-		self.code_hash.clone().unwrap_or(SHA3_EMPTY)
+		self.code_hash.clone()
 	}

 	/// return the code hash associated with this account.
@@ -187,41 +215,35 @@ impl Account {

 	/// returns the account's code. If `None` then the code cache isn't available -
 	/// get someone who knows to call `note_code`.
-	pub fn code(&self) -> Option<&[u8]> {
-		match self.code_hash {
-			Some(c) if c == SHA3_EMPTY && self.code_cache.is_empty() => Some(&self.code_cache),
-			Some(_) if !self.code_cache.is_empty() => Some(&self.code_cache),
-			None => Some(&self.code_cache),
-			_ => None,
+	pub fn code(&self) -> Option<Arc<Bytes>> {
+		if self.code_hash != SHA3_EMPTY && self.code_cache.is_empty() {
+			return None;
 		}
+		Some(self.code_cache.clone())
+	}
+
+	/// returns the account's code size. If `None` then the code cache or code size cache isn't available -
+	/// get someone who knows to call `note_code`.
+	pub fn code_size(&self) -> Option<u64> {
+		self.code_size.clone()
 	}

 	#[cfg(test)]
 	/// Provide a byte array which hashes to the `code_hash`. returns the hash as a result.
 	pub fn note_code(&mut self, code: Bytes) -> Result<(), H256> {
 		let h = code.sha3();
-		match self.code_hash {
-			Some(ref i) if h == *i => {
-				self.code_cache = code;
-				Ok(())
-			},
-			_ => Err(h)
+		if self.code_hash == h {
+			self.code_cache = Arc::new(code);
+			self.code_size = Some(self.code_cache.len() as u64);
+			Ok(())
+		} else {
+			Err(h)
 		}
 	}

 	/// Is `code_cache` valid; such that code is going to return Some?
 	pub fn is_cached(&self) -> bool {
-		!self.code_cache.is_empty() || (self.code_cache.is_empty() && self.code_hash == Some(SHA3_EMPTY))
-	}
-
-	/// Is this a new or modified account?
-	pub fn is_dirty(&self) -> bool {
-		self.filth == Filth::Dirty
-	}
-
-	/// Mark account as clean.
-	pub fn set_clean(&mut self) {
-		self.filth = Filth::Clean
+		!self.code_cache.is_empty() || (self.code_cache.is_empty() && self.code_hash == SHA3_EMPTY)
 	}

 	/// Provide a database to get `code_hash`. Should not be called if it is a contract without code.
@@ -229,83 +251,100 @@ impl Account {
 		// TODO: fill out self.code_cache;
 		trace!("Account::cache_code: ic={}; self.code_hash={:?}, self.code_cache={}", self.is_cached(), self.code_hash, self.code_cache.pretty());
 		self.is_cached() ||
-			match self.code_hash {
-				Some(ref h) => match db.get(h) {
-					Some(x) => { self.code_cache = x.to_vec(); true },
+		match db.get(&self.code_hash) {
+			Some(x) => {
+				self.code_cache = Arc::new(x.to_vec());
+				self.code_size = Some(x.len() as u64);
+				true
+			},
+			_ => {
+				warn!("Failed reverse get of {}", self.code_hash);
+				false
+			},
+		}
+	}
+
+	/// Provide a database to get `code_size`. Should not be called if it is a contract without code.
+	pub fn cache_code_size(&mut self, db: &AccountDB) -> bool {
+		// TODO: fill out self.code_cache;
+		trace!("Account::cache_code_size: ic={}; self.code_hash={:?}, self.code_cache={}", self.is_cached(), self.code_hash, self.code_cache.pretty());
+		self.code_size.is_some() ||
+			if self.code_hash != SHA3_EMPTY {
+				match db.get(&self.code_hash) {
+					Some(x) => {
+						self.code_size = Some(x.len() as u64);
+						true
+					},
 					_ => {
-						warn!("Failed reverse get of {}", h);
+						warn!("Failed reverse get of {}", self.code_hash);
 						false
 					},
-				},
-				_ => false,
+				}
+			} else {
+				false
 			}
 	}

-	#[cfg(test)]
 	/// Determine whether there are any un-`commit()`-ed storage-setting operations.
-	pub fn storage_is_clean(&self) -> bool { self.storage_overlay.borrow().iter().find(|&(_, &(f, _))| f == Filth::Dirty).is_none() }
+	pub fn storage_is_clean(&self) -> bool { self.storage_changes.is_empty() }

 	#[cfg(test)]
 	/// return the storage root associated with this account or None if it has been altered via the overlay.
 	pub fn storage_root(&self) -> Option<&H256> { if self.storage_is_clean() {Some(&self.storage_root)} else {None} }

 	/// return the storage overlay.
-	pub fn storage_overlay(&self) -> Ref<HashMap<H256, (Filth, H256)>> { self.storage_overlay.borrow() }
+	pub fn storage_changes(&self) -> &HashMap<H256, H256> { &self.storage_changes }

 	/// Increment the nonce of the account by one.
 	pub fn inc_nonce(&mut self) {
 		self.nonce = self.nonce + U256::from(1u8);
-		self.filth = Filth::Dirty;
 	}

-	/// Increment the nonce of the account by one.
+	/// Increase account balance.
 	pub fn add_balance(&mut self, x: &U256) {
-		if !x.is_zero() {
-			self.balance = self.balance + *x;
-			self.filth = Filth::Dirty;
-		}
+		self.balance = self.balance + *x;
 	}

-	/// Increment the nonce of the account by one.
+	/// Decrease account balance.
 	/// Panics if balance is less than `x`
 	pub fn sub_balance(&mut self, x: &U256) {
-		if !x.is_zero() {
-			assert!(self.balance >= *x);
-			self.balance = self.balance - *x;
-			self.filth = Filth::Dirty;
-		}
+		assert!(self.balance >= *x);
+		self.balance = self.balance - *x;
 	}

-	/// Commit the `storage_overlay` to the backing DB and update `storage_root`.
+	/// Commit the `storage_changes` to the backing DB and update `storage_root`.
 	pub fn commit_storage(&mut self, trie_factory: &TrieFactory, db: &mut AccountDBMut) {
 		let mut t = trie_factory.from_existing(db, &mut self.storage_root)
 			.expect("Account storage_root initially set to zero (valid) and only altered by SecTrieDBMut. \
 				SecTrieDBMut would not set it to an invalid state root. Therefore the root is valid and DB creation \
 				using it will not fail.");
-		for (k, &mut (ref mut f, ref mut v)) in self.storage_overlay.borrow_mut().iter_mut() {
-			if f == &Filth::Dirty {
-				// cast key and value to trait type,
-				// so we can call overloaded `to_bytes` method
-				let res = match v.is_zero() {
-					true => t.remove(k),
-					false => t.insert(k, &encode(&U256::from(v.as_slice()))),
-				};
+		for (k, v) in self.storage_changes.drain() {
+			// cast key and value to trait type,
+			// so we can call overloaded `to_bytes` method
+			let res = match v.is_zero() {
+				true => t.remove(k.as_slice()),
+				false => t.insert(k.as_slice(), &encode(&U256::from(v.as_slice()))),
+			};

-				if let Err(e) = res {
-					warn!("Encountered potential DB corruption: {}", e);
-				}
-				*f = Filth::Clean;
+			if let Err(e) = res {
+				warn!("Encountered potential DB corruption: {}", e);
 			}
+			self.storage_cache.borrow_mut().insert(k, v);
 		}
 	}

 	/// Commit any unsaved code. `code_hash` will always return the hash of the `code_cache` after this.
 	pub fn commit_code(&mut self, db: &mut AccountDBMut) {
-		trace!("Commiting code of {:?} - {:?}, {:?}", self, self.code_hash.is_none(), self.code_cache.is_empty());
-		match (self.code_hash.is_none(), self.code_cache.is_empty()) {
-			(true, true) => self.code_hash = Some(SHA3_EMPTY),
+		trace!("Commiting code of {:?} - {:?}, {:?}", self, self.code_filth == Filth::Dirty, self.code_cache.is_empty());
+		match (self.code_filth == Filth::Dirty, self.code_cache.is_empty()) {
+			(true, true) => {
+				self.code_size = Some(0);
+				self.code_filth = Filth::Clean;
+			},
 			(true, false) => {
-				self.code_hash = Some(db.insert(&self.code_cache));
+				db.emplace(self.code_hash.clone(), (*self.code_cache).clone());
+				self.code_size = Some(self.code_cache.len() as u64);
+				self.code_filth = Filth::Clean;
 			},
 			(false, _) => {},
 		}
@@ -317,9 +356,59 @@ impl Account {
 		stream.append(&self.nonce);
 		stream.append(&self.balance);
 		stream.append(&self.storage_root);
-		stream.append(self.code_hash.as_ref().expect("Cannot form RLP of contract account without code."));
+		stream.append(&self.code_hash);
 		stream.out()
 	}
+
+	/// Clone basic account data
+	pub fn clone_basic(&self) -> Account {
+		Account {
+			balance: self.balance.clone(),
+			nonce: self.nonce.clone(),
+			storage_root: self.storage_root.clone(),
+			storage_cache: Self::empty_storage_cache(),
+			storage_changes: HashMap::new(),
+			code_hash: self.code_hash.clone(),
+			code_size: self.code_size.clone(),
+			code_cache: self.code_cache.clone(),
+			code_filth: self.code_filth,
+			address_hash: self.address_hash.clone(),
+		}
+	}
+
+	/// Clone account data and dirty storage keys
+	pub fn clone_dirty(&self) -> Account {
+		let mut account = self.clone_basic();
+		account.storage_changes = self.storage_changes.clone();
+		account.code_cache = self.code_cache.clone();
+		account
+	}
+
+	/// Clone account data, dirty storage keys and cached storage keys.
+	pub fn clone_all(&self) -> Account {
+		let mut account = self.clone_dirty();
+		account.storage_cache = self.storage_cache.clone();
+		account
+	}
+
+	/// Replace self with the data from other account merging storage cache.
+	/// Basic account data and all modifications are overwritten
+	/// with new values.
+	pub fn overwrite_with(&mut self, other: Account) {
+		self.balance = other.balance;
+		self.nonce = other.nonce;
+		self.storage_root = other.storage_root;
+		self.code_hash = other.code_hash;
+		self.code_filth = other.code_filth;
+		self.code_cache = other.code_cache;
+		self.code_size = other.code_size;
+		self.address_hash = other.address_hash;
+		let mut cache = self.storage_cache.borrow_mut();
+		for (k, v) in other.storage_cache.into_inner().into_iter() {
+			cache.insert(k.clone() , v.clone()); //TODO: cloning should not be required here
+		}
+		self.storage_changes = other.storage_changes;
+	}
 }

 impl fmt::Debug for Account {
@@ -414,7 +503,8 @@ mod tests {
 		let mut db = MemoryDB::new();
 		let mut db = AccountDBMut::new(&mut db, &Address::new());
 		a.init_code(vec![0x55, 0x44, 0xffu8]);
-		assert_eq!(a.code_hash(), SHA3_EMPTY);
+		assert_eq!(a.code_filth, Filth::Dirty);
+		assert_eq!(a.code_size(), Some(3));
 		a.commit_code(&mut db);
 		assert_eq!(a.code_hash().hex(), "af231e631776a517ca23125370d542873eca1fb4d613ed9b5d5335a46ae5b7eb");
 	}
@@ -425,11 +515,12 @@ mod tests {
 		let mut db = MemoryDB::new();
 		let mut db = AccountDBMut::new(&mut db, &Address::new());
 		a.init_code(vec![0x55, 0x44, 0xffu8]);
-		assert_eq!(a.code_hash(), SHA3_EMPTY);
+		assert_eq!(a.code_filth, Filth::Dirty);
 		a.commit_code(&mut db);
+		assert_eq!(a.code_filth, Filth::Clean);
 		assert_eq!(a.code_hash().hex(), "af231e631776a517ca23125370d542873eca1fb4d613ed9b5d5335a46ae5b7eb");
 		a.reset_code(vec![0x55]);
-		assert_eq!(a.code_hash(), SHA3_EMPTY);
+		assert_eq!(a.code_filth, Filth::Dirty);
 		a.commit_code(&mut db);
 		assert_eq!(a.code_hash().hex(), "37bf2238b11b68cdc8382cece82651b59d3c3988873b6e0f33d79694aa45f1be");
 	}
--- a/ethcore/src/action_params.rs
+++ b/ethcore/src/action_params.rs
@@ -43,6 +43,8 @@ impl ActionValue {
 pub struct ActionParams {
 	/// Address of currently executed code.
 	pub code_address: Address,
+	/// Hash of currently executed code.
+	pub code_hash: H256,
 	/// Receive address. Usually equal to code_address,
 	/// except when called using CALLCODE.
 	pub address: Address,
@@ -57,7 +59,7 @@ pub struct ActionParams {
 	/// Transaction value.
 	pub value: ActionValue,
 	/// Code being executed.
-	pub code: Option<Bytes>,
+	pub code: Option<Arc<Bytes>>,
 	/// Input data.
 	pub data: Option<Bytes>,
 	/// Type of call
@@ -70,6 +72,7 @@ impl Default for ActionParams {
 	fn default() -> ActionParams {
 		ActionParams {
 			code_address: Address::new(),
+			code_hash: SHA3_EMPTY,
 			address: Address::new(),
 			sender: Address::new(),
 			origin: Address::new(),
@@ -88,10 +91,11 @@ impl From<ethjson::vm::Transaction> for ActionParams {
 		let address: Address = t.address.into();
 		ActionParams {
 			code_address: Address::new(),
+			code_hash: (&*t.code).sha3(),
 			address: address,
 			sender: t.sender.into(),
 			origin: t.origin.into(),
-			code: Some(t.code.into()),
+			code: Some(Arc::new(t.code.into())),
 			data: Some(t.data.into()),
 			gas: t.gas.into(),
 			gas_price: t.gas_price.into(),
--- a/ethcore/src/block.rs
+++ b/ethcore/src/block.rs
@@ -19,6 +19,7 @@
 use common::*;
 use engines::Engine;
 use state::*;
+use state_db::StateDB;
 use verification::PreverifiedBlock;
 use trace::FlatTrace;
 use evm::Factory as EvmFactory;
@@ -178,7 +179,7 @@ pub trait IsBlock {
 /// Trait for a object that has a state database.
 pub trait Drain {
 	/// Drop this object and return the underlieing database.
-	fn drain(self) -> Box<JournalDB>;
+	fn drain(self) -> StateDB;
 }

 impl IsBlock for ExecutedBlock {
@@ -233,7 +234,7 @@ impl<'x> OpenBlock<'x> {
 		vm_factory: &'x EvmFactory,
 		trie_factory: TrieFactory,
 		tracing: bool,
-		db: Box<JournalDB>,
+		db: StateDB,
 		parent: &Header,
 		last_hashes: Arc<LastHashes>,
 		author: Address,
@@ -465,7 +466,9 @@ impl LockedBlock {

 impl Drain for LockedBlock {
 	/// Drop this object and return the underlieing database.
-	fn drain(self) -> Box<JournalDB> { self.block.state.drop().1 }
+	fn drain(self) -> StateDB {
+		self.block.state.drop().1
+	}
 }

 impl SealedBlock {
@@ -481,7 +484,9 @@ impl SealedBlock {

 impl Drain for SealedBlock {
 	/// Drop this object and return the underlieing database.
-	fn drain(self) -> Box<JournalDB> { self.block.state.drop().1 }
+	fn drain(self) -> StateDB {
+		self.block.state.drop().1
+	}
 }

 impl IsBlock for SealedBlock {
@@ -496,7 +501,7 @@ pub fn enact(
 	uncles: &[Header],
 	engine: &Engine,
 	tracing: bool,
-	db: Box<JournalDB>,
+	db: StateDB,
 	parent: &Header,
 	last_hashes: Arc<LastHashes>,
 	vm_factory: &EvmFactory,
@@ -529,7 +534,7 @@ pub fn enact_bytes(
 	block_bytes: &[u8],
 	engine: &Engine,
 	tracing: bool,
-	db: Box<JournalDB>,
+	db: StateDB,
 	parent: &Header,
 	last_hashes: Arc<LastHashes>,
 	vm_factory: &EvmFactory,
@@ -546,7 +551,7 @@ pub fn enact_verified(
 	block: &PreverifiedBlock,
 	engine: &Engine,
 	tracing: bool,
-	db: Box<JournalDB>,
+	db: StateDB,
 	parent: &Header,
 	last_hashes: Arc<LastHashes>,
 	vm_factory: &EvmFactory,
@@ -562,7 +567,7 @@ pub fn enact_and_seal(
 	block_bytes: &[u8],
 	engine: &Engine,
 	tracing: bool,
-	db: Box<JournalDB>,
+	db: StateDB,
 	parent: &Header,
 	last_hashes: Arc<LastHashes>,
 	vm_factory: &EvmFactory,
@@ -583,9 +588,9 @@ mod tests {
 		use spec::*;
 		let spec = Spec::new_test();
 		let genesis_header = spec.genesis_header();
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let last_hashes = Arc::new(vec![genesis_header.hash()]);
 		let vm_factory = Default::default();
 		let b = OpenBlock::new(&*spec.engine, &vm_factory, Default::default(), false, db, &genesis_header, last_hashes, Address::zero(), (3141562.into(), 31415620.into()), vec![]).unwrap();
@@ -600,9 +605,9 @@ mod tests {
 		let engine = &*spec.engine;
 		let genesis_header = spec.genesis_header();

-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let vm_factory = Default::default();
 		let last_hashes = Arc::new(vec![genesis_header.hash()]);
 		let b = OpenBlock::new(engine, &vm_factory, Default::default(), false, db, &genesis_header, last_hashes.clone(), Address::zero(), (3141562.into(), 31415620.into()), vec![]).unwrap()
@@ -610,16 +615,16 @@ mod tests {
 		let orig_bytes = b.rlp_bytes();
 		let orig_db = b.drain();

-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let e = enact_and_seal(&orig_bytes, engine, false, db, &genesis_header, last_hashes, &Default::default(), Default::default()).unwrap();

 		assert_eq!(e.rlp_bytes(), orig_bytes);

 		let db = e.drain();
-		assert_eq!(orig_db.keys(), db.keys());
-		assert!(orig_db.keys().iter().filter(|k| orig_db.get(k.0) != db.get(k.0)).next() == None);
+		assert_eq!(orig_db.journal_db().keys(), db.journal_db().keys());
+		assert!(orig_db.journal_db().keys().iter().filter(|k| orig_db.journal_db().get(k.0) != db.journal_db().get(k.0)).next() == None);
 	}

 	#[test]
@@ -629,9 +634,9 @@ mod tests {
 		let engine = &*spec.engine;
 		let genesis_header = spec.genesis_header();

-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let vm_factory = Default::default();
 		let last_hashes = Arc::new(vec![genesis_header.hash()]);
 		let mut open_block = OpenBlock::new(engine, &vm_factory, Default::default(), false, db, &genesis_header, last_hashes.clone(), Address::zero(), (3141562.into(), 31415620.into()), vec![]).unwrap();
@@ -646,9 +651,9 @@ mod tests {
 		let orig_bytes = b.rlp_bytes();
 		let orig_db = b.drain();

-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let e = enact_and_seal(&orig_bytes, engine, false, db, &genesis_header, last_hashes, &Default::default(), Default::default()).unwrap();

 		let bytes = e.rlp_bytes();
@@ -657,7 +662,7 @@ mod tests {
 		assert_eq!(uncles[1].extra_data, b"uncle2");

 		let db = e.drain();
-		assert_eq!(orig_db.keys(), db.keys());
-		assert!(orig_db.keys().iter().filter(|k| orig_db.get(k.0) != db.get(k.0)).next() == None);
+		assert_eq!(orig_db.journal_db().keys(), db.journal_db().keys());
+		assert!(orig_db.journal_db().keys().iter().filter(|k| orig_db.journal_db().get(k.0) != db.journal_db().get(k.0)).next() == None);
 	}
 }
--- a/ethcore/src/blockchain/blockchain.rs
+++ b/ethcore/src/blockchain/blockchain.rs
@@ -165,7 +165,7 @@ pub struct BlockChain {

 	pending_best_block: RwLock<Option<BestBlock>>,
 	pending_block_hashes: RwLock<HashMap<BlockNumber, H256>>,
-	pending_transaction_addresses: RwLock<HashMap<H256, TransactionAddress>>,
+	pending_transaction_addresses: RwLock<HashMap<H256, Option<TransactionAddress>>>,
 }

 impl BlockProvider for BlockChain {
@@ -584,8 +584,8 @@ impl BlockChain {
 				block_hashes: self.prepare_block_hashes_update(bytes, &info),
 				block_details: self.prepare_block_details_update(bytes, &info),
 				block_receipts: self.prepare_block_receipts_update(receipts, &info),
-				transactions_addresses: self.prepare_transaction_addresses_update(bytes, &info),
 				blocks_blooms: self.prepare_block_blooms_update(bytes, &info),
+				transactions_addresses: self.prepare_transaction_addresses_update(bytes, &info),
 				info: info,
 				block: bytes
 			}, is_best);
@@ -618,8 +618,8 @@ impl BlockChain {
 				block_hashes: self.prepare_block_hashes_update(bytes, &info),
 				block_details: update,
 				block_receipts: self.prepare_block_receipts_update(receipts, &info),
-				transactions_addresses: self.prepare_transaction_addresses_update(bytes, &info),
 				blocks_blooms: self.prepare_block_blooms_update(bytes, &info),
+				transactions_addresses: self.prepare_transaction_addresses_update(bytes, &info),
 				info: info,
 				block: bytes,
 			}, is_best);
@@ -687,8 +687,8 @@ impl BlockChain {
 			block_hashes: self.prepare_block_hashes_update(bytes, &info),
 			block_details: self.prepare_block_details_update(bytes, &info),
 			block_receipts: self.prepare_block_receipts_update(receipts, &info),
-			transactions_addresses: self.prepare_transaction_addresses_update(bytes, &info),
 			blocks_blooms: self.prepare_block_blooms_update(bytes, &info),
+			transactions_addresses: self.prepare_transaction_addresses_update(bytes, &info),
 			info: info.clone(),
 			block: bytes,
 		}, true);
@@ -744,8 +744,9 @@ impl BlockChain {
 			let mut write_details = self.block_details.write();
 			batch.extend_with_cache(DB_COL_EXTRA, &mut *write_details, update.block_details, CacheUpdatePolicy::Overwrite);

+			let mut cache_man = self.cache_man.write();
 			for hash in block_hashes.into_iter() {
-				self.note_used(CacheID::BlockDetails(hash));
+				cache_man.note_used(CacheID::BlockDetails(hash));
 			}
 		}

@@ -780,7 +781,7 @@ impl BlockChain {
 			let mut write_txs = self.pending_transaction_addresses.write();

 			batch.extend_with_cache(DB_COL_EXTRA, &mut *write_hashes, update.block_hashes, CacheUpdatePolicy::Overwrite);
-			batch.extend_with_cache(DB_COL_EXTRA, &mut *write_txs, update.transactions_addresses, CacheUpdatePolicy::Overwrite);
+			batch.extend_with_option_cache(DB_COL_EXTRA, &mut *write_txs, update.transactions_addresses, CacheUpdatePolicy::Overwrite);
 		}
 	}

@@ -798,18 +799,26 @@ impl BlockChain {
 			*best_block = block;
 		}

+		let pending_txs = mem::replace(&mut *pending_write_txs, HashMap::new());
+		let (retracted_txs, enacted_txs) = pending_txs.into_iter().partition::<HashMap<_, _>, _>(|&(_, ref value)| value.is_none());
+
 		let pending_hashes_keys: Vec<_> = pending_write_hashes.keys().cloned().collect();
-		let pending_txs_keys: Vec<_> = pending_write_txs.keys().cloned().collect();
+		let enacted_txs_keys: Vec<_> = enacted_txs.keys().cloned().collect();

 		write_hashes.extend(mem::replace(&mut *pending_write_hashes, HashMap::new()));
-		write_txs.extend(mem::replace(&mut *pending_write_txs, HashMap::new()));
+		write_txs.extend(enacted_txs.into_iter().map(|(k, v)| (k, v.expect("Transactions were partitioned; qed"))));

-		for n in pending_hashes_keys.into_iter() {
-			self.note_used(CacheID::BlockHashes(n));
+		for hash in retracted_txs.keys() {
+			write_txs.remove(hash);
 		}

-		for hash in pending_txs_keys.into_iter() {
-			self.note_used(CacheID::TransactionAddresses(hash));
+		let mut cache_man = self.cache_man.write();
+		for n in pending_hashes_keys.into_iter() {
+			cache_man.note_used(CacheID::BlockHashes(n));
+		}
+
+		for hash in enacted_txs_keys {
+			cache_man.note_used(CacheID::TransactionAddresses(hash));
 		}
 	}

@@ -910,7 +919,7 @@ impl BlockChain {
 	}

 	/// This function returns modified transaction addresses.
-	fn prepare_transaction_addresses_update(&self, block_bytes: &[u8], info: &BlockInfo) -> HashMap<H256, TransactionAddress> {
+	fn prepare_transaction_addresses_update(&self, block_bytes: &[u8], info: &BlockInfo) -> HashMap<H256, Option<TransactionAddress>> {
 		let block = BlockView::new(block_bytes);
 		let transaction_hashes = block.transaction_hashes();

@@ -919,10 +928,10 @@ impl BlockChain {
 				transaction_hashes.into_iter()
 					.enumerate()
 					.map(|(i ,tx_hash)| {
-						(tx_hash, TransactionAddress {
+						(tx_hash, Some(TransactionAddress {
 							block_hash: info.hash.clone(),
 							index: i
-						})
+						}))
 					})
 					.collect()
 			},
@@ -933,23 +942,30 @@ impl BlockChain {
 						let hashes = BodyView::new(&bytes).transaction_hashes();
 						hashes.into_iter()
 							.enumerate()
-							.map(|(i, tx_hash)| (tx_hash, TransactionAddress {
+							.map(|(i, tx_hash)| (tx_hash, Some(TransactionAddress {
 								block_hash: hash.clone(),
 								index: i,
-							}))
-							.collect::<HashMap<H256, TransactionAddress>>()
+							})))
+							.collect::<HashMap<H256, Option<TransactionAddress>>>()
 					});

 				let current_addresses = transaction_hashes.into_iter()
 					.enumerate()
 					.map(|(i ,tx_hash)| {
-						(tx_hash, TransactionAddress {
+						(tx_hash, Some(TransactionAddress {
 							block_hash: info.hash.clone(),
 							index: i
-						})
+						}))
 					});

-				addresses.chain(current_addresses).collect()
+				let retracted = data.retracted.iter().flat_map(|hash| {
+					let bytes = self.block_body(hash).expect("Retracted block must be in database.");
+					let hashes = BodyView::new(&bytes).transaction_hashes();
+					hashes.into_iter().map(|hash| (hash, None)).collect::<HashMap<H256, Option<TransactionAddress>>>()
+				});
+
+				// The order here is important! Don't remove transaction if it was part of enacted blocks as well.
+				retracted.chain(addresses).chain(current_addresses).collect()
 			},
 			BlockLocation::Branch => HashMap::new(),
 		}
@@ -1248,6 +1264,70 @@ mod tests {
 		// TODO: insert block that already includes one of them as an uncle to check it's not allowed.
 	}

+	#[test]
+	fn test_fork_transaction_addresses() {
+		let mut canon_chain = ChainGenerator::default();
+		let mut finalizer = BlockFinalizer::default();
+		let genesis = canon_chain.generate(&mut finalizer).unwrap();
+		let mut fork_chain = canon_chain.fork(1);
+		let mut fork_finalizer = finalizer.fork();
+
+		let t1 = Transaction {
+			nonce: 0.into(),
+			gas_price: 0.into(),
+			gas: 100_000.into(),
+			action: Action::Create,
+			value: 100.into(),
+			data: "601080600c6000396000f3006000355415600957005b60203560003555".from_hex().unwrap(),
+		}.sign(&"".sha3());
+
+
+		let b1a = canon_chain
+			.with_transaction(t1.clone())
+			.generate(&mut finalizer).unwrap();
+
+		// Empty block
+		let b1b = fork_chain
+			.generate(&mut fork_finalizer).unwrap();
+
+		let b2 = fork_chain
+			.generate(&mut fork_finalizer).unwrap();
+
+		let b1a_hash = BlockView::new(&b1a).header_view().sha3();
+		let b2_hash = BlockView::new(&b2).header_view().sha3();
+
+		let t1_hash = t1.hash();
+
+		let temp = RandomTempPath::new();
+		let db = new_db(temp.as_str());
+		let bc = BlockChain::new(Config::default(), &genesis, db.clone());
+
+		let mut batch = db.transaction();
+		let _ = bc.insert_block(&mut batch, &b1a, vec![]);
+		bc.commit();
+		let _ = bc.insert_block(&mut batch, &b1b, vec![]);
+		bc.commit();
+		db.write(batch).unwrap();
+
+		assert_eq!(bc.best_block_hash(), b1a_hash);
+		assert_eq!(bc.transaction_address(&t1_hash), Some(TransactionAddress {
+			block_hash: b1a_hash.clone(),
+			index: 0,
+		}));
+
+		// now let's make forked chain the canon chain
+		let mut batch = db.transaction();
+		let _ = bc.insert_block(&mut batch, &b2, vec![]);
+		bc.commit();
+		db.write(batch).unwrap();
+
+		// Transaction should be retracted
+		assert_eq!(bc.best_block_hash(), b2_hash);
+		assert_eq!(bc.transaction_address(&t1_hash), None);
+	}
+
+
+
 	#[test]
 	fn test_overwriting_transaction_addresses() {
 		let mut canon_chain = ChainGenerator::default();
@@ -1318,14 +1398,14 @@ mod tests {
 		db.write(batch).unwrap();

 		assert_eq!(bc.best_block_hash(), b1a_hash);
-		assert_eq!(bc.transaction_address(&t1_hash).unwrap(), TransactionAddress {
+		assert_eq!(bc.transaction_address(&t1_hash), Some(TransactionAddress {
 			block_hash: b1a_hash.clone(),
 			index: 0,
-		});
-		assert_eq!(bc.transaction_address(&t2_hash).unwrap(), TransactionAddress {
+		}));
+		assert_eq!(bc.transaction_address(&t2_hash), Some(TransactionAddress {
 			block_hash: b1a_hash.clone(),
 			index: 1,
-		});
+		}));

 		// now let's make forked chain the canon chain
 		let mut batch = db.transaction();
@@ -1334,18 +1414,18 @@ mod tests {
 		db.write(batch).unwrap();

 		assert_eq!(bc.best_block_hash(), b2_hash);
-		assert_eq!(bc.transaction_address(&t1_hash).unwrap(), TransactionAddress {
+		assert_eq!(bc.transaction_address(&t1_hash), Some(TransactionAddress {
 			block_hash: b1b_hash.clone(),
 			index: 1,
-		});
-		assert_eq!(bc.transaction_address(&t2_hash).unwrap(), TransactionAddress {
+		}));
+		assert_eq!(bc.transaction_address(&t2_hash), Some(TransactionAddress {
 			block_hash: b1b_hash.clone(),
 			index: 0,
-		});
-		assert_eq!(bc.transaction_address(&t3_hash).unwrap(), TransactionAddress {
+		}));
+		assert_eq!(bc.transaction_address(&t3_hash), Some(TransactionAddress {
 			block_hash: b2_hash.clone(),
 			index: 0,
-		});
+		}));
 	}

 	#[test]
--- a/ethcore/src/blockchain/update.rs
+++ b/ethcore/src/blockchain/update.rs
@@ -17,8 +17,8 @@ pub struct ExtrasUpdate<'a> {
 	pub block_details: HashMap<H256, BlockDetails>,
 	/// Modified block receipts.
 	pub block_receipts: HashMap<H256, BlockReceipts>,
-	/// Modified transaction addresses.
-	pub transactions_addresses: HashMap<H256, TransactionAddress>,
 	/// Modified blocks blooms.
 	pub blocks_blooms: HashMap<LogGroupPosition, BloomGroup>,
+	/// Modified transaction addresses (None signifies removed transactions).
+	pub transactions_addresses: HashMap<H256, Option<TransactionAddress>>,
 }
--- a/ethcore/src/client/client.rs
+++ b/ethcore/src/client/client.rs
@@ -23,7 +23,6 @@ use time::precise_time_ns;

 // util
 use util::{journaldb, rlp, Bytes, View, PerfTimer, Itertools, Mutex, RwLock};
-use util::journaldb::JournalDB;
 use util::rlp::{UntrustedRlp};
 use util::numbers::*;
 use util::sha3::*;
@@ -65,6 +64,7 @@ use evm::Factory as EvmFactory;
 use miner::{Miner, MinerService};
 use util::TrieFactory;
 use snapshot::{self, io as snapshot_io};
+use state_db::StateDB;

 // re-export
 pub use types::blockchain_info::BlockChainInfo;
@@ -124,7 +124,7 @@ pub struct Client {
 	tracedb: Arc<TraceDB<BlockChain>>,
 	engine: Arc<Engine>,
 	db: Arc<Database>,
-	state_db: Mutex<Box<JournalDB>>,
+	state_db: Mutex<StateDB>,
 	block_queue: BlockQueue,
 	report: RwLock<ClientReport>,
 	import_lock: Mutex<()>,
@@ -154,15 +154,10 @@ pub const DB_COL_BODIES: Option<u32> = Some(2);
 pub const DB_COL_EXTRA: Option<u32> = Some(3);
 /// Column for Traces
 pub const DB_COL_TRACE: Option<u32> = Some(4);
+/// Column for Traces
+pub const DB_COL_ACCOUNT_BLOOM: Option<u32> = Some(5);
 /// Number of columns in DB
-pub const DB_NO_OF_COLUMNS: Option<u32> = Some(5);
-
-/// Append a path element to the given path and return the string.
-pub fn append_path<P>(path: P, item: &str) -> String where P: AsRef<Path> {
-	let mut p = path.as_ref().to_path_buf();
-	p.push(item);
-	p.to_str().unwrap().to_owned()
-}
+pub const DB_NO_OF_COLUMNS: Option<u32> = Some(6);

 impl Client {
 	/// Create a new client with given spec and DB path and custom verifier.
@@ -180,18 +175,19 @@ impl Client {
 		db_config.compaction = config.db_compaction.compaction_profile();
 		db_config.wal = config.db_wal;

-		let db = Arc::new(try!(Database::open(&db_config, &path.to_str().unwrap()).map_err(ClientError::Database)));
+		let db = Arc::new(try!(Database::open(&db_config, &path.to_str().expect("DB path could not be converted to string.")).map_err(ClientError::Database)));
 		let chain = Arc::new(BlockChain::new(config.blockchain, &gb, db.clone()));
 		let tracedb = Arc::new(try!(TraceDB::new(config.tracing, db.clone(), chain.clone())));

-		let mut state_db = journaldb::new(db.clone(), config.pruning, DB_COL_STATE);
-		if state_db.is_empty() && try!(spec.ensure_db_good(state_db.as_hashdb_mut())) {
+		let journal_db = journaldb::new(db.clone(), config.pruning, DB_COL_STATE);
+		let mut state_db = StateDB::new(journal_db);
+		if state_db.journal_db().is_empty() && try!(spec.ensure_db_good(&mut state_db)) {
 			let batch = DBTransaction::new(&db);
 			try!(state_db.commit(&batch, 0, &spec.genesis_header().hash(), None));
 			try!(db.write(batch).map_err(ClientError::Database));
 		}

-		if !chain.block_header(&chain.best_block_hash()).map_or(true, |h| state_db.contains(h.state_root())) {
+		if !chain.block_header(&chain.best_block_hash()).map_or(true, |h| state_db.journal_db().contains(h.state_root())) {
 			warn!("State root not found for block #{} ({})", chain.best_block_number(), chain.best_block_hash().hex());
 		}

@@ -292,31 +288,28 @@ impl Client {
 		};

 		// Check if Parent is in chain
-		let chain_has_parent = self.chain.block_header(&header.parent_hash);
-		if let None = chain_has_parent {
-			warn!(target: "client", "Block import failed for #{} ({}): Parent not found ({}) ", header.number(), header.hash(), header.parent_hash);
-			return Err(());
-		};
+		let chain_has_parent = self.chain.block_header(header.parent_hash());
+		if let Some(parent) = chain_has_parent {
+			// Enact Verified Block
+			let last_hashes = self.build_last_hashes(header.parent_hash().clone());
+			let db = self.state_db.lock().boxed_clone_canon(&header.parent_hash());

-		// Enact Verified Block
-		let parent = chain_has_parent.unwrap();
-		let last_hashes = self.build_last_hashes(header.parent_hash.clone());
-		let db = self.state_db.lock().boxed_clone();
+			let enact_result = enact_verified(block, engine, self.tracedb.tracing_enabled(), db, &parent, last_hashes, &self.vm_factory, self.trie_factory.clone());
+			let locked_block = try!(enact_result.map_err(|e| {
+				warn!(target: "client", "Block import failed for #{} ({})\nError: {:?}", header.number(), header.hash(), e);
+			}));

-		let enact_result = enact_verified(block, engine, self.tracedb.tracing_enabled(), db, &parent, last_hashes, &self.vm_factory, self.trie_factory.clone());
-		if let Err(e) = enact_result {
-			warn!(target: "client", "Block import failed for #{} ({})\nError: {:?}", header.number(), header.hash(), e);
-			return Err(());
-		};
+			// Final Verification
+			if let Err(e) = self.verifier.verify_block_final(header, locked_block.block().header()) {
+				warn!(target: "client", "Stage 4 block verification failed for #{} ({})\nError: {:?}", header.number(), header.hash(), e);
+				return Err(());
+			}

-		// Final Verification
-		let locked_block = enact_result.unwrap();
-		if let Err(e) = self.verifier.verify_block_final(header, locked_block.block().header()) {
-			warn!(target: "client", "Stage 4 block verification failed for #{} ({})\nError: {:?}", header.number(), header.hash(), e);
-			return Err(());
+			Ok(locked_block)
+		} else {
+			warn!(target: "client", "Block import failed for #{} ({}): Parent not found ({}) ", header.number(), header.hash(), header.parent_hash());
+			Err(())
 		}
-
-		Ok(locked_block)
 	}

 	fn calculate_enacted_retracted(&self, import_results: &[ImportRoute]) -> (Vec<H256>, Vec<H256>) {
@@ -369,14 +362,17 @@ impl Client {
 					invalid_blocks.insert(header.hash());
 					continue;
 				}
+				let is_invalid = invalid_blocks.contains(header.parent_hash());
+				if let (false, Ok(closed_block)) = (is_invalid, self.check_and_close_block(&block)) {
+					imported_blocks.push(header.hash());

-				let closed_block = closed_block.unwrap();
-				imported_blocks.push(header.hash());
+					let route = self.commit_block(closed_block, &header.hash(), &block.bytes);
+					import_results.push(route);

-				let route = self.commit_block(closed_block, &header.hash(), &block.bytes);
-				import_results.push(route);
-
-				self.report.write().accrue_block(&block);
+					self.report.write().accrue_block(&block);
+				} else {
+					invalid_blocks.insert(header.hash());
+				}
 			}

 			let imported = imported_blocks.len();
@@ -425,7 +421,7 @@ impl Client {
 		// Are we committing an era?
 		let ancient = if number >= HISTORY {
 			let n = number - HISTORY;
-			Some((n, self.chain.block_hash(n).unwrap()))
+			Some((n, self.chain.block_hash(n).expect("only verified blocks can be commited; verified block has hash; qed")))
 		} else {
 			None
 		};
@@ -438,12 +434,12 @@ impl Client {
 			.collect();

 		//let traces = From::from(block.traces().clone().unwrap_or_else(Vec::new));
-
 		let batch = DBTransaction::new(&self.db);
 		// CHECK! I *think* this is fine, even if the state_root is equal to another
 		// already-imported block of the same number.
 		// TODO: Prove it with a test.
-		block.drain().commit(&batch, number, hash, ancient).expect("DB commit failed.");
+		let mut state = block.drain();
+		state.commit(&batch, number, hash, ancient).expect("DB commit failed.");

 		let route = self.chain.insert_block(&batch, block_data, receipts);
 		self.tracedb.import(&batch, TraceImportRequest {
@@ -453,10 +449,11 @@ impl Client {
 			enacted: route.enacted.clone(),
 			retracted: route.retracted.len()
 		});
+		let is_canon = route.enacted.last().map_or(false, |h| h == hash);
+		state.sync_cache(&route.enacted, &route.retracted, is_canon);
 		// Final commit to the DB
 		self.db.write_buffered(batch).expect("DB write failed.");
 		self.chain.commit();
-
 		self.update_last_hashes(&parent, hash);
 		route
 	}
@@ -528,9 +525,11 @@ impl Client {

 	/// Get a copy of the best block's state.
 	pub fn state(&self) -> State {
+		let header = self.best_block_header();
+		let header = HeaderView::new(&header);
 		State::from_existing(
-			self.state_db.lock().boxed_clone(),
-			HeaderView::new(&self.best_block_header()).state_root(),
+			self.state_db.lock().boxed_clone_canon(&header.hash()),
+			header.state_root(),
 			self.engine.account_start_nonce(),
 			self.trie_factory.clone())
 		.expect("State root of best block header always valid.")
@@ -600,7 +599,7 @@ impl Client {
 	/// Take a snapshot at the given block.
 	/// If the ID given is "latest", this will default to 1000 blocks behind.
 	pub fn take_snapshot<W: snapshot_io::SnapshotWriter + Send>(&self, writer: W, at: BlockID, p: &snapshot::Progress) -> Result<(), ::error::Error> {
-		let db = self.state_db.lock().boxed_clone();
+		let db = self.state_db.lock().journal_db().boxed_clone();
 		let best_block_number = self.chain_info().best_block_number;
 		let block_number = try!(self.block_number(at).ok_or(snapshot::Error::InvalidStartingBlock(at)));

@@ -804,7 +803,7 @@ impl BlockChainClient for Client {
 	}

 	fn code(&self, address: &Address, id: BlockID) -> Option<Option<Bytes>> {
-		self.state_at(id).map(|s| s.code(address))
+		self.state_at(id).map(|s| s.code(address).map(|c| (*c).clone()))
 	}

 	fn balance(&self, address: &Address, id: BlockID) -> Option<U256> {
@@ -829,8 +828,9 @@ impl BlockChainClient for Client {
 			let t = self.chain.block_body(&address.block_hash)
 				.and_then(|block| BodyView::new(&block).localized_transaction_at(&address.block_hash, block_number, address.index));

-			match (t, self.chain.transaction_receipt(&address)) {
-				(Some(tx), Some(receipt)) => {
+			let tx_and_sender = t.and_then(|tx| tx.sender().ok().map(|sender| (tx, sender)));
+			match (tx_and_sender, self.chain.transaction_receipt(&address)) {
+				(Some((tx, sender)), Some(receipt)) => {
 					let block_hash = tx.block_hash.clone();
 					let block_number = tx.block_number.clone();
 					let transaction_hash = tx.hash();
@@ -852,7 +852,7 @@ impl BlockChainClient for Client {
 						gas_used: receipt.gas_used - prior_gas_used,
 						contract_address: match tx.action {
 							Action::Call(_) => None,
-							Action::Create => Some(contract_address(&tx.sender().unwrap(), &tx.nonce))
+							Action::Create => Some(contract_address(&sender, &tx.nonce))
 						},
 						logs: receipt.logs.into_iter().enumerate().map(|(i, log)| LocalizedLogEntry {
 							entry: log,
@@ -881,7 +881,7 @@ impl BlockChainClient for Client {
 	}

 	fn state_data(&self, hash: &H256) -> Option<Bytes> {
-		self.state_db.lock().state(hash)
+		self.state_db.lock().journal_db().state(hash)
 	}

 	fn block_receipts(&self, hash: &H256) -> Option<Bytes> {
@@ -975,17 +975,18 @@ impl BlockChainClient for Client {
 		let start = self.block_number(filter.range.start);
 		let end = self.block_number(filter.range.end);

-		if start.is_some() && end.is_some() {
-			let filter = trace::Filter {
-				range: start.unwrap() as usize..end.unwrap() as usize,
-				from_address: From::from(filter.from_address),
-				to_address: From::from(filter.to_address),
-			};
+		match (start, end) {
+			(Some(s), Some(e)) => {
+				let filter = trace::Filter {
+					range: s as usize..e as usize,
+					from_address: From::from(filter.from_address),
+					to_address: From::from(filter.to_address),
+				};

-			let traces = self.tracedb.filter(&filter);
-			Some(traces)
-		} else {
-			None
+				let traces = self.tracedb.filter(&filter);
+				Some(traces)
+			},
+			_ => None,
 		}
 	}

@@ -1032,7 +1033,7 @@ impl BlockChainClient for Client {
 	}

 	fn pending_transactions(&self) -> Vec<SignedTransaction> {
-		self.miner.pending_transactions()
+		self.miner.pending_transactions(self.chain.best_block_number())
 	}
 }

@@ -1046,7 +1047,7 @@ impl MiningBlockChainClient for Client {
 			&self.vm_factory,
 			self.trie_factory.clone(),
 			false,	// TODO: this will need to be parameterised once we want to do immediate mining insertion.
-			self.state_db.lock().boxed_clone(),
+			self.state_db.lock().boxed_clone_canon(&h),
 			&self.chain.block_header(&h).expect("h is best block hash: so its header must exist: qed"),
 			self.build_last_hashes(h.clone()),
 			author,
@@ -1057,11 +1058,15 @@ impl MiningBlockChainClient for Client {
 		// Add uncles
 		self.chain
 			.find_uncle_headers(&h, engine.maximum_uncle_age())
-			.unwrap()
+			.unwrap_or_else(Vec::new)
 			.into_iter()
 			.take(engine.maximum_uncle_count())
 			.foreach(|h| {
-				open_block.push_uncle(h).unwrap();
+				open_block.push_uncle(h).expect("pushing maximum_uncle_count;
+												open_block was just created;
+												push_uncle is not ok only if more than maximum_uncle_count is pushed;
+												so all push_uncle are Ok;
+												qed");
 			});

 		open_block
@@ -1080,8 +1085,10 @@ impl MiningBlockChainClient for Client {
 		let number = block.header().number();

 		let block_data = block.rlp_bytes();
+		// Clear canonical state cache
 		let route = self.commit_block(block, &h, &block_data);
 		trace!(target: "client", "Imported sealed block #{} ({})", number, h);
+		self.state_db.lock().sync_cache(&route.enacted, &route.retracted, false);

 		let (enacted, retracted) = self.calculate_enacted_retracted(&[route]);
 		self.miner.chain_new_blocks(self, &[h.clone()], &[], &enacted, &retracted);
--- a/ethcore/src/client/test_client.rs
+++ b/ethcore/src/client/test_client.rs
@@ -23,7 +23,8 @@ use transaction::{Transaction, LocalizedTransaction, SignedTransaction, Action};
 use blockchain::TreeRoute;
 use client::{
 	BlockChainClient, MiningBlockChainClient, BlockChainInfo, BlockStatus, BlockID,
-	TransactionID, UncleID, TraceId, TraceFilter, LastHashes, CallAnalytics, BlockImportError
+	TransactionID, UncleID, TraceId, TraceFilter, LastHashes, CallAnalytics, BlockImportError,
+	DB_NO_OF_COLUMNS, DB_COL_STATE,
 };
 use header::{Header as BlockHeader, BlockNumber};
 use filter::Filter;
@@ -40,6 +41,7 @@ use block::{OpenBlock, SealedBlock};
 use executive::Executed;
 use error::CallError;
 use trace::LocalizedTrace;
+use state_db::StateDB;

 /// Test client.
 pub struct TestBlockChainClient {
@@ -51,6 +53,8 @@ pub struct TestBlockChainClient {
 	pub genesis_hash: H256,
 	/// Last block hash.
 	pub last_hash: RwLock<H256>,
+	/// Extra data do set for each block
+	pub extra_data: Bytes,
 	/// Difficulty.
 	pub difficulty: RwLock<U256>,
 	/// Balances.
@@ -97,11 +101,17 @@ impl Default for TestBlockChainClient {
 impl TestBlockChainClient {
 	/// Creates new test client.
 	pub fn new() -> Self {
+		Self::new_with_extra_data(Bytes::new())
+	}
+
+	/// Creates new test client with specified extra data for each block
+	pub fn new_with_extra_data(extra_data: Bytes) -> Self {
 		let spec = Spec::new_test();
 		let mut client = TestBlockChainClient {
 			blocks: RwLock::new(HashMap::new()),
 			numbers: RwLock::new(HashMap::new()),
 			genesis_hash: H256::new(),
+			extra_data: extra_data,
 			last_hash: RwLock::new(H256::new()),
 			difficulty: RwLock::new(From::from(0)),
 			balances: RwLock::new(HashMap::new()),
@@ -119,7 +129,7 @@ impl TestBlockChainClient {
 		client.genesis_hash = client.last_hash.read().clone();
 		client
 	}
-
+	
 	/// Set the transaction receipt result
 	pub fn set_transaction_receipt(&self, id: TransactionID, receipt: LocalizedReceipt) {
 		self.receipts.write().insert(id, receipt);
@@ -164,6 +174,7 @@ impl TestBlockChainClient {
 			header.parent_hash = self.last_hash.read().clone();
 			header.number = n as BlockNumber;
 			header.gas_limit = U256::from(1_000_000);
+			header.extra_data = self.extra_data.clone();
 			let uncles = match with {
 				EachBlockWith::Uncle | EachBlockWith::UncleAndTransaction => {
 					let mut uncles = RlpStream::new_list(1);
@@ -247,13 +258,14 @@ impl TestBlockChainClient {
 	}
 }

-pub fn get_temp_journal_db() -> GuardedTempResult<Box<JournalDB>> {
+pub fn get_temp_state_db() -> GuardedTempResult<StateDB> {
 	let temp = RandomTempPath::new();
-	let db = Database::open_default(temp.as_str()).unwrap();
-	let journal_db = journaldb::new(Arc::new(db), journaldb::Algorithm::EarlyMerge, None);
+	let db = Database::open(&DatabaseConfig::with_columns(DB_NO_OF_COLUMNS), temp.as_str()).unwrap();
+	let journal_db = journaldb::new(Arc::new(db), journaldb::Algorithm::EarlyMerge, DB_COL_STATE);
+	let state_db = StateDB::new(journal_db);
 	GuardedTempResult {
 		_temp: temp,
-		result: Some(journal_db)
+		result: Some(state_db)
 	}
 }

@@ -261,9 +273,9 @@ impl MiningBlockChainClient for TestBlockChainClient {
 	fn prepare_open_block(&self, author: Address, gas_range_target: (U256, U256), extra_data: Bytes) -> OpenBlock {
 		let engine = &*self.spec.engine;
 		let genesis_header = self.spec.genesis_header();
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		self.spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		self.spec.ensure_db_good(&mut db).unwrap();

 		let last_hashes = vec![genesis_header.hash()];
 		let mut open_block = OpenBlock::new(
@@ -348,11 +360,11 @@ impl BlockChainClient for TestBlockChainClient {
 	}

 	fn transaction(&self, _id: TransactionID) -> Option<LocalizedTransaction> {
-		unimplemented!();
+		None
 	}

 	fn uncle(&self, _id: UncleID) -> Option<Bytes> {
-		unimplemented!();
+		None
 	}

 	fn transaction_receipt(&self, id: TransactionID) -> Option<LocalizedReceipt> {
@@ -555,6 +567,6 @@ impl BlockChainClient for TestBlockChainClient {
 	}

 	fn pending_transactions(&self) -> Vec<SignedTransaction> {
-		self.miner.pending_transactions()
+		self.miner.pending_transactions(self.chain_info().best_block_number)
 	}
 }
--- a/ethcore/src/db.rs
+++ b/ethcore/src/db.rs
@@ -64,6 +64,9 @@ pub trait Writable {
 	/// Writes the value into the database.
 	fn write<T, R>(&self, col: Option<u32>, key: &Key<T, Target = R>, value: &T) where T: Encodable, R: Deref<Target = [u8]>;

+	/// Deletes key from the databse.
+	fn delete<T, R>(&self, col: Option<u32>, key: &Key<T, Target = R>) where T: Encodable, R: Deref<Target = [u8]>;
+
 	/// Writes the value into the database and updates the cache.
 	fn write_with_cache<K, T, R>(&self, col: Option<u32>, cache: &mut Cache<K, T>, key: K, value: T, policy: CacheUpdatePolicy) where
 	K: Key<T, Target = R> + Hash + Eq,
@@ -100,6 +103,34 @@ pub trait Writable {
 			},
 		}
 	}
+
+	/// Writes and removes the values into the database and updates the cache.
+	fn extend_with_option_cache<K, T, R>(&self, col: Option<u32>, cache: &mut Cache<K, Option<T>>, values: HashMap<K, Option<T>>, policy: CacheUpdatePolicy) where
+	K: Key<T, Target = R> + Hash + Eq,
+	T: Encodable,
+	R: Deref<Target = [u8]> {
+		match policy {
+			CacheUpdatePolicy::Overwrite => {
+				for (key, value) in values.into_iter() {
+					match value {
+						Some(ref v) => self.write(col, &key, v),
+						None => self.delete(col, &key),
+					}
+					cache.insert(key, value);
+				}
+			},
+			CacheUpdatePolicy::Remove => {
+				for (key, value) in values.into_iter() {
+					match value {
+						Some(v) => self.write(col, &key, &v),
+						None => self.delete(col, &key),
+					}
+					cache.remove(&key);
+				}
+			},
+		}
+	}
+
 }

 /// Should be used to read values from database.
@@ -154,6 +185,13 @@ impl Writable for DBTransaction {
 			panic!("db put failed, key: {:?}, err: {:?}", &key.key() as &[u8], err);
 		}
 	}
+
+	fn delete<T, R>(&self, col: Option<u32>, key: &Key<T, Target = R>) where T: Encodable, R: Deref<Target = [u8]> {
+		let result = DBTransaction::delete(self, col, &key.key());
+		if let Err(err) = result {
+			panic!("db delete failed, key: {:?}, err: {:?}", &key.key() as &[u8], err);
+		}
+	}
 }

 impl Readable for Database {
--- a/ethcore/src/engines/basic_authority.rs
+++ b/ethcore/src/engines/basic_authority.rs
@@ -248,9 +248,9 @@ mod tests {
 		let spec = new_test_authority();
 		let engine = &*spec.engine;
 		let genesis_header = spec.genesis_header();
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let last_hashes = Arc::new(vec![genesis_header.hash()]);
 		let vm_factory = Default::default();
 		let b = OpenBlock::new(engine, &vm_factory, Default::default(), false, db, &genesis_header, last_hashes, addr, (3141562.into(), 31415620.into()), vec![]).unwrap();
--- a/ethcore/src/engines/instant_seal.rs
+++ b/ethcore/src/engines/instant_seal.rs
@@ -82,9 +82,9 @@ mod tests {
 		let spec = new_test_instant();
 		let engine = &*spec.engine;
 		let genesis_header = spec.genesis_header();
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let last_hashes = Arc::new(vec![genesis_header.hash()]);
 		let vm_factory = Default::default();
 		let b = OpenBlock::new(engine, &vm_factory, Default::default(), false, db, &genesis_header, last_hashes, addr, (3141562.into(), 31415620.into()), vec![]).unwrap();
--- a/ethcore/src/ethereum/ethash.rs
+++ b/ethcore/src/ethereum/ethash.rs
@@ -353,9 +353,9 @@ mod tests {
 		let spec = new_morden();
 		let engine = &*spec.engine;
 		let genesis_header = spec.genesis_header();
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let last_hashes = Arc::new(vec![genesis_header.hash()]);
 		let vm_factory = Default::default();
 		let b = OpenBlock::new(engine, &vm_factory, Default::default(), false, db, &genesis_header, last_hashes, Address::zero(), (3141562.into(), 31415620.into()), vec![]).unwrap();
@@ -368,9 +368,9 @@ mod tests {
 		let spec = new_morden();
 		let engine = &*spec.engine;
 		let genesis_header = spec.genesis_header();
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let last_hashes = Arc::new(vec![genesis_header.hash()]);
 		let vm_factory = Default::default();
 		let mut b = OpenBlock::new(engine, &vm_factory, Default::default(), false, db, &genesis_header, last_hashes, Address::zero(), (3141562.into(), 31415620.into()), vec![]).unwrap();
--- a/ethcore/src/ethereum/mod.rs
+++ b/ethcore/src/ethereum/mod.rs
@@ -65,9 +65,9 @@ mod tests {
 		let spec = new_morden();
 		let engine = &spec.engine;
 		let genesis_header = spec.genesis_header();
-		let mut db_result = get_temp_journal_db();
+		let mut db_result = get_temp_state_db();
 		let mut db = db_result.take();
-		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+		spec.ensure_db_good(&mut db).unwrap();
 		let s = State::from_existing(db, genesis_header.state_root.clone(), engine.account_start_nonce(), Default::default()).unwrap();
 		assert_eq!(s.balance(&address_from_hex("0000000000000000000000000000000000000001")), U256::from(1u64));
 		assert_eq!(s.balance(&address_from_hex("0000000000000000000000000000000000000002")), U256::from(1u64));
--- a/ethcore/src/evm/ext.rs
+++ b/ethcore/src/evm/ext.rs
@@ -81,7 +81,10 @@ pub trait Ext {
 	) -> MessageCallResult;

 	/// Returns code at given address
-	fn extcode(&self, address: &Address) -> Bytes;
+	fn extcode(&self, address: &Address) -> Arc<Bytes>;
+
+	/// Returns code length in bytes at given address
+	fn extcode_len(&self, address: &Address) -> u64;

 	/// Creates log entry with given topics and data
 	fn log(&mut self, topics: Vec<H256>, data: &[u8]);
--- a/ethcore/src/evm/factory.rs
+++ b/ethcore/src/evm/factory.rs
@@ -18,8 +18,10 @@
 //!
 //! TODO: consider spliting it into two separate files.
 use std::fmt;
+use std::sync::Arc;
 use evm::Evm;
 use util::{U256, Uint};
+use super::interpreter::SharedCache;

 #[derive(Debug, PartialEq, Clone)]
 /// Type of EVM to use.
@@ -81,7 +83,8 @@ impl VMType {

 /// Evm factory. Creates appropriate Evm.
 pub struct Factory {
-	evm: VMType
+	evm: VMType,
+	evm_cache: Arc<SharedCache>,
 }

 impl Factory {
@@ -94,9 +97,9 @@ impl Factory {
 				Box::new(super::jit::JitEvm::default())
 			},
 			VMType::Interpreter => if Self::can_fit_in_usize(gas) {
-				Box::new(super::interpreter::Interpreter::<usize>::default())
+				Box::new(super::interpreter::Interpreter::<usize>::new(self.evm_cache.clone()))
 			} else {
-				Box::new(super::interpreter::Interpreter::<U256>::default())
+				Box::new(super::interpreter::Interpreter::<U256>::new(self.evm_cache.clone()))
 			}
 		}
 	}
@@ -107,9 +110,9 @@ impl Factory {
 	pub fn create(&self, gas: U256) -> Box<Evm> {
 		match self.evm {
 			VMType::Interpreter => if Self::can_fit_in_usize(gas) {
-				Box::new(super::interpreter::Interpreter::<usize>::default())
+				Box::new(super::interpreter::Interpreter::<usize>::new(self.evm_cache.clone()))
 			} else {
-				Box::new(super::interpreter::Interpreter::<U256>::default())
+				Box::new(super::interpreter::Interpreter::<U256>::new(self.evm_cache.clone()))
 			}
 		}
 	}
@@ -117,7 +120,8 @@ impl Factory {
 	/// Create new instance of specific `VMType` factory
 	pub fn new(evm: VMType) -> Self {
 		Factory {
-			evm: evm
+			evm: evm,
+			evm_cache: Arc::new(SharedCache::default()),
 		}
 	}

@@ -131,7 +135,8 @@ impl Default for Factory {
 	#[cfg(feature = "jit")]
 	fn default() -> Factory {
 		Factory {
-			evm: VMType::Jit
+			evm: VMType::Jit,
+			evm_cache: Arc::new(SharedCache::default()),
 		}
 	}

@@ -139,7 +144,8 @@ impl Default for Factory {
 	#[cfg(not(feature = "jit"))]
 	fn default() -> Factory {
 		Factory {
-			evm: VMType::Interpreter
+			evm: VMType::Interpreter,
+			evm_cache: Arc::new(SharedCache::default()),
 		}
 	}
 }
--- a/ethcore/src/evm/interpreter/mod.rs
+++ b/ethcore/src/evm/interpreter/mod.rs
@@ -31,10 +31,12 @@ macro_rules! evm_debug {
 mod gasometer;
 mod stack;
 mod memory;
+mod shared_cache;

 use self::gasometer::Gasometer;
 use self::stack::{Stack, VecStack};
 use self::memory::Memory;
+pub use self::shared_cache::SharedCache;

 use std::marker::PhantomData;
 use common::*;
@@ -53,6 +55,17 @@ fn color(instruction: Instruction, name: &'static str) -> String {
 type CodePosition = usize;
 type ProgramCounter = usize;

+const ONE: U256 = U256([1, 0, 0, 0]);
+const TWO: U256 = U256([2, 0, 0, 0]);
+const TWO_POW_5: U256 = U256([0x20, 0, 0, 0]);
+const TWO_POW_8: U256 = U256([0x100, 0, 0, 0]);
+const TWO_POW_16: U256 = U256([0x10000, 0, 0, 0]);
+const TWO_POW_24: U256 = U256([0x1000000, 0, 0, 0]);
+const TWO_POW_64: U256 = U256([0, 0x1, 0, 0]); // 0x1 00000000 00000000
+const TWO_POW_96: U256 = U256([0, 0x100000000, 0, 0]); //0x1 00000000 00000000 00000000
+const TWO_POW_224: U256 = U256([0, 0, 0, 0x100000000]); //0x1 00000000 00000000 00000000 00000000 00000000 00000000 00000000
+const TWO_POW_248: U256 = U256([0, 0, 0, 0x100000000000000]); //0x1 00000000 00000000 00000000 00000000 00000000 00000000 00000000 000000
+
 /// Abstraction over raw vector of Bytes. Easier state management of PC.
 struct CodeReader<'a> {
 	position: ProgramCounter,
@@ -87,9 +100,9 @@ enum InstructionResult<Gas> {


 /// Intepreter EVM implementation
-#[derive(Default)]
 pub struct Interpreter<Cost: CostType> {
 	mem: Vec<u8>,
+	cache: Arc<SharedCache>,
 	_type: PhantomData<Cost>,
 }

@@ -98,7 +111,7 @@ impl<Cost: CostType> evm::Evm for Interpreter<Cost> {
 		self.mem.clear();

 		let code = &params.code.as_ref().unwrap();
-		let valid_jump_destinations = self.find_jump_destinations(code);
+		let valid_jump_destinations = self.cache.jump_destinations(&params.code_hash, code);

 		let mut gasometer = Gasometer::<Cost>::new(try!(Cost::from_u256(params.gas)));
 		let mut stack = VecStack::with_capacity(ext.schedule().stack_limit, U256::zero());
@@ -177,6 +190,14 @@ impl<Cost: CostType> evm::Evm for Interpreter<Cost> {
 }

 impl<Cost: CostType> Interpreter<Cost> {
+	/// Create a new `Interpreter` instance with shared cache.
+	pub fn new(cache: Arc<SharedCache>) -> Interpreter<Cost> {
+		Interpreter {
+			mem: Vec::new(),
+			cache: cache,
+			_type: PhantomData::default(),
+		}
+	}

 	fn verify_instruction(&self, ext: &evm::Ext, instruction: Instruction, info: &InstructionInfo, stack: &Stack<U256>) -> evm::Result<()> {
 		let schedule = ext.schedule();
@@ -471,14 +492,14 @@ impl<Cost: CostType> Interpreter<Cost> {
 			},
 			instructions::EXTCODESIZE => {
 				let address = u256_to_address(&stack.pop_back());
-				let len = ext.extcode(&address).len();
+				let len = ext.extcode_len(&address);
 				stack.push(U256::from(len));
 			},
 			instructions::CALLDATACOPY => {
-				self.copy_data_to_memory(stack, &params.data.clone().unwrap_or_else(|| vec![]));
+				self.copy_data_to_memory(stack, params.data.as_ref().map_or_else(|| &[] as &[u8], |d| &*d as &[u8]));
 			},
 			instructions::CODECOPY => {
-				self.copy_data_to_memory(stack, &params.code.clone().unwrap_or_else(|| vec![]));
+				self.copy_data_to_memory(stack, params.code.as_ref().map_or_else(|| &[] as &[u8], |c| &**c as &[u8]));
 			},
 			instructions::EXTCODECOPY => {
 				let address = u256_to_address(&stack.pop_back());
@@ -599,7 +620,19 @@ impl<Cost: CostType> Interpreter<Cost> {
 				let a = stack.pop_back();
 				let b = stack.pop_back();
 				stack.push(if !self.is_zero(&b) {
-					a.overflowing_div(b).0
+					match b {
+						ONE => a,
+						TWO => a >> 1,
+						TWO_POW_5 => a >> 5,
+						TWO_POW_8 => a >> 8,
+						TWO_POW_16 => a >> 16,
+						TWO_POW_24 => a >> 24,
+						TWO_POW_64 => a >> 64,
+						TWO_POW_96 => a >> 96,
+						TWO_POW_224 => a >> 224,
+						TWO_POW_248 => a >> 248,
+						_ => a.overflowing_div(b).0,
+					}
 				} else {
 					U256::zero()
 				});
@@ -767,23 +800,6 @@ impl<Cost: CostType> Interpreter<Cost> {
 		Ok(())
 	}

-	fn find_jump_destinations(&self, code: &[u8]) -> BitSet {
-		let mut jump_dests = BitSet::with_capacity(code.len());
-		let mut position = 0;
-
-		while position < code.len() {
-			let instruction = code[position];
-
-			if instruction == instructions::JUMPDEST {
-				jump_dests.insert(position);
-			} else if instructions::is_push(instruction) {
-				position += instructions::get_push_bytes(instruction);
-			}
-			position += 1;
-		}
-
-		jump_dests
-	}
 }

 fn get_and_reset_sign(value: U256) -> (U256, bool) {
@@ -810,15 +826,3 @@ fn address_to_u256(value: Address) -> U256 {
 	U256::from(H256::from(value).as_slice())
 }

-#[test]
-fn test_find_jump_destinations() {
-	// given
-	let interpreter = Interpreter::<U256>::default();
-	let code = "7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff5b01600055".from_hex().unwrap();
-
-	// when
-	let valid_jump_destinations = interpreter.find_jump_destinations(&code);
-
-	// then
-	assert!(valid_jump_destinations.contains(66));
-}
--- a/ethcore/src/evm/interpreter/shared_cache.rs
+++ b/ethcore/src/evm/interpreter/shared_cache.rs
@@ -0,0 +1,84 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+use std::sync::Arc;
+use lru_cache::LruCache;
+use util::{H256, Mutex};
+use util::sha3::*;
+use bit_set::BitSet;
+use super::super::instructions;
+
+const CACHE_CODE_ITEMS: usize = 65536;
+
+/// GLobal cache for EVM interpreter
+pub struct SharedCache {
+	jump_destinations: Mutex<LruCache<H256, Arc<BitSet>>>
+}
+
+impl SharedCache {
+	/// Get jump destincations bitmap for a contract.
+	pub fn jump_destinations(&self, code_hash: &H256, code: &[u8]) -> Arc<BitSet> {
+		if code_hash == &SHA3_EMPTY {
+			return Self::find_jump_destinations(code);
+		}
+		if let Some(d) = self.jump_destinations.lock().get_mut(code_hash) {
+			return d.clone();
+		}
+
+		let d = Self::find_jump_destinations(code);
+		self.jump_destinations.lock().insert(code_hash.clone(), d.clone());
+		d
+	}
+
+	fn find_jump_destinations(code: &[u8]) -> Arc<BitSet> {
+		let mut jump_dests = BitSet::with_capacity(code.len());
+		let mut position = 0;
+
+		while position < code.len() {
+			let instruction = code[position];
+
+			if instruction == instructions::JUMPDEST {
+				jump_dests.insert(position);
+			} else if instructions::is_push(instruction) {
+				position += instructions::get_push_bytes(instruction);
+			}
+			position += 1;
+		}
+		Arc::new(jump_dests)
+	}
+}
+
+impl Default for SharedCache {
+	fn default() -> SharedCache {
+		SharedCache {
+			jump_destinations: Mutex::new(LruCache::new(CACHE_CODE_ITEMS)),
+		}
+	}
+}
+
+
+#[test]
+fn test_find_jump_destinations() {
+	use util::FromHex;
+	// given
+	let code = "7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff5b01600055".from_hex().unwrap();
+
+	// when
+	let valid_jump_destinations = SharedCache::find_jump_destinations(&code);
+
+	// then
+	assert!(valid_jump_destinations.contains(66));
+}
--- a/ethcore/src/evm/jit.rs
+++ b/ethcore/src/evm/jit.rs
@@ -18,6 +18,7 @@
 use common::*;
 use evmjit;
 use evm::{self, GasLeft};
+use types::executed::CallType;

 /// Should be used to convert jit types to ethcore
 trait FromJit<T>: Sized {
@@ -77,10 +78,11 @@ impl IntoJit<evmjit::I256> for U256 {
 impl IntoJit<evmjit::I256> for H256 {
 	fn into_jit(self) -> evmjit::I256 {
 		let mut ret = [0; 4];
-		for i in 0..self.bytes().len() {
-			let rev = self.bytes().len() - 1 - i;
+		let len = self.len();
+		for i in 0..len {
+			let rev = len - 1 - i;
 			let pos = rev / 8;
-			ret[pos] += (self.bytes()[i] as u64) << ((rev % 8) * 8);
+			ret[pos] += (self[i] as u64) << ((rev % 8) * 8);
 		}
 		evmjit::I256 { words: ret }
 	}
@@ -194,6 +196,7 @@ impl<'a> evmjit::Ext for ExtAdapter<'a> {
 				receive_address: *const evmjit::H256,
 				code_address: *const evmjit::H256,
 				transfer_value: *const evmjit::I256,
+				// Ignoring apparent value - it's handled correctly in executive.
 				_apparent_value: *const evmjit::I256,
 				in_beg: *const u8,
 				in_size: u64,
@@ -207,10 +210,12 @@ impl<'a> evmjit::Ext for ExtAdapter<'a> {
 		let receive_address = unsafe { Address::from_jit(&*receive_address) };
 		let code_address = unsafe { Address::from_jit(&*code_address) };
 		let transfer_value = unsafe { U256::from_jit(&*transfer_value) };
-		let value = Some(transfer_value);

 		// receive address and code address are the same in normal calls
 		let is_callcode = receive_address != code_address;
+		let is_delegatecall = is_callcode && sender_address != receive_address;
+
+		let value = if is_delegatecall { None } else { Some(transfer_value) };

 		if !is_callcode && !self.ext.exists(&code_address) {
 			gas_cost = gas_cost + U256::from(self.ext.schedule().call_new_account_gas);
@@ -239,6 +244,12 @@ impl<'a> evmjit::Ext for ExtAdapter<'a> {
 			}
 		}

+		let call_type = match (is_callcode, is_delegatecall) {
+			(_, true) => CallType::DelegateCall,
+			(true, false) => CallType::CallCode,
+			(false, false) => CallType::Call,
+		};
+
 		match self.ext.call(
 					  &call_gas,
 					  &sender_address,
@@ -246,7 +257,9 @@ impl<'a> evmjit::Ext for ExtAdapter<'a> {
 					  value,
 					  unsafe { slice::from_raw_parts(in_beg, in_size as usize) },
 					  &code_address,
-					  unsafe { slice::from_raw_parts_mut(out_beg, out_size as usize) }) {
+					  unsafe { slice::from_raw_parts_mut(out_beg, out_size as usize) },
+					  call_type,
+					  ) {
 			evm::MessageCallResult::Success(gas_left) => unsafe {
 				*io_gas = (gas + gas_left).low_u64();
 				true
--- a/ethcore/src/evm/tests.rs
+++ b/ethcore/src/evm/tests.rs
@@ -49,7 +49,7 @@ pub struct FakeExt {
 	depth: usize,
 	store: HashMap<H256, H256>,
 	blockhashes: HashMap<U256, H256>,
-	codes: HashMap<Address, Bytes>,
+	codes: HashMap<Address, Arc<Bytes>>,
 	logs: Vec<FakeLogEntry>,
 	_suicides: HashSet<Address>,
 	info: EnvInfo,
@@ -136,8 +136,12 @@ impl Ext for FakeExt {
 		MessageCallResult::Success(*gas)
 	}

-	fn extcode(&self, address: &Address) -> Bytes {
-		self.codes.get(address).unwrap_or(&Bytes::new()).clone()
+	fn extcode(&self, address: &Address) -> Arc<Bytes> {
+		self.codes.get(address).unwrap_or(&Arc::new(Bytes::new())).clone()
+	}
+
+	fn extcode_len(&self, address: &Address) -> u64 {
+		self.codes.get(address).map_or(0, |c| c.len() as u64)
 	}

 	fn log(&mut self, topics: Vec<H256>, data: &[u8]) {
@@ -180,11 +184,11 @@ fn test_stack_underflow() {
 	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let err = {
-		let mut vm : Box<evm::Evm> = Box::new(super::interpreter::Interpreter::<usize>::default());
+		let mut vm : Box<evm::Evm> = Box::new(super::interpreter::Interpreter::<usize>::new(Arc::new(super::interpreter::SharedCache::default())));
 		test_finalize(vm.exec(params, &mut ext)).unwrap_err()
 	};

@@ -207,7 +211,7 @@ fn test_add(factory: super::Factory) {
 	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -227,7 +231,7 @@ fn test_sha3(factory: super::Factory) {
 	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -247,7 +251,7 @@ fn test_address(factory: super::Factory) {
 	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -269,7 +273,7 @@ fn test_origin(factory: super::Factory) {
 	params.address = address.clone();
 	params.origin = origin.clone();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -291,7 +295,7 @@ fn test_sender(factory: super::Factory) {
 	params.address = address.clone();
 	params.sender = sender.clone();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -325,9 +329,9 @@ fn test_extcodecopy(factory: super::Factory) {
 	params.address = address.clone();
 	params.sender = sender.clone();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();
-	ext.codes.insert(sender, sender_code);
+	ext.codes.insert(sender, Arc::new(sender_code));

 	let gas_left = {
 		let mut vm = factory.create(params.gas);
@@ -346,7 +350,7 @@ fn test_log_empty(factory: super::Factory) {
 	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -378,7 +382,7 @@ fn test_log_sender(factory: super::Factory) {
 	params.address = address.clone();
 	params.sender = sender.clone();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -402,7 +406,7 @@ fn test_blockhash(factory: super::Factory) {
 	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();
 	ext.blockhashes.insert(U256::zero(), blockhash.clone());

@@ -424,7 +428,7 @@ fn test_calldataload(factory: super::Factory) {
 	let mut params = ActionParams::default();
 	params.address = address.clone();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	params.data = Some(data);
 	let mut ext = FakeExt::new();

@@ -445,7 +449,7 @@ fn test_author(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();
 	ext.info.author = author;

@@ -465,7 +469,7 @@ fn test_timestamp(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();
 	ext.info.timestamp = timestamp;

@@ -485,7 +489,7 @@ fn test_number(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();
 	ext.info.number = number;

@@ -505,7 +509,7 @@ fn test_difficulty(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();
 	ext.info.difficulty = difficulty;

@@ -525,7 +529,7 @@ fn test_gas_limit(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();
 	ext.info.gas_limit = gas_limit;

@@ -544,7 +548,7 @@ fn test_mul(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -562,7 +566,7 @@ fn test_sub(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -580,7 +584,7 @@ fn test_div(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -598,7 +602,7 @@ fn test_div_zero(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -616,7 +620,7 @@ fn test_mod(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -635,7 +639,7 @@ fn test_smod(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -654,7 +658,7 @@ fn test_sdiv(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -673,7 +677,7 @@ fn test_exp(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -693,7 +697,7 @@ fn test_comparison(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -714,7 +718,7 @@ fn test_signed_comparison(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -735,7 +739,7 @@ fn test_bitops(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(150_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -758,7 +762,7 @@ fn test_addmod_mulmod(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -779,7 +783,7 @@ fn test_byte(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -798,7 +802,7 @@ fn test_signextend(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -818,7 +822,7 @@ fn test_badinstruction_int() {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let err = {
@@ -838,7 +842,7 @@ fn test_pop(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(100_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -858,7 +862,7 @@ fn test_extops(factory: super::Factory) {
 	params.gas = U256::from(150_000);
 	params.gas_price = U256::from(0x32);
 	params.value = ActionValue::Transfer(U256::from(0x99));
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -881,7 +885,7 @@ fn test_jumps(factory: super::Factory) {

 	let mut params = ActionParams::default();
 	params.gas = U256::from(150_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	let mut ext = FakeExt::new();

 	let gas_left = {
@@ -904,7 +908,7 @@ fn test_calls(factory: super::Factory) {
 	let code_address = Address::from(0x998);
 	let mut params = ActionParams::default();
 	params.gas = U256::from(150_000);
-	params.code = Some(code);
+	params.code = Some(Arc::new(code));
 	params.address = address.clone();
 	let mut ext = FakeExt::new();
 	ext.balances = {
--- a/ethcore/src/executive.rs
+++ b/ethcore/src/executive.rs
@@ -26,10 +26,10 @@ use trace::{FlatTrace, Tracer, NoopTracer, ExecutiveTracer, VMTrace, VMTracer, E
 use crossbeam;
 pub use types::executed::{Executed, ExecutionResult};

-/// Max depth to avoid stack overflow (when it's reached we start a new thread with VM)
+/// Roughly estimate what stack size each level of evm depth will use
 /// TODO [todr] We probably need some more sophisticated calculations here (limit on my machine 132)
 /// Maybe something like here: `https://github.com/ethereum/libethereum/blob/4db169b8504f2b87f7d5a481819cfb959fc65f6c/libethereum/ExtVM.cpp`
-const MAX_VM_DEPTH_FOR_THREAD: usize = 64;
+const STACK_SIZE_PER_DEPTH: usize = 24*1024;

 /// Returns new address created from address and given nonce.
 pub fn contract_address(address: &Address, nonce: &U256) -> Address {
@@ -148,12 +148,13 @@ impl<'a> Executive<'a> {

 		// TODO: we might need bigints here, or at least check overflows.
 		let balance = self.state.balance(&sender);
-		let gas_cost = U512::from(t.gas) * U512::from(t.gas_price);
+		let gas_cost = t.gas.full_mul(t.gas_price);
 		let total_cost = U512::from(t.value) + gas_cost;

 		// avoid unaffordable transactions
-		if U512::from(balance) < total_cost {
-			return Err(From::from(ExecutionError::NotEnoughCash { required: total_cost, got: U512::from(balance) }));
+		let balance512 = U512::from(balance);
+		if balance512 < total_cost {
+			return Err(From::from(ExecutionError::NotEnoughCash { required: total_cost, got: balance512 }));
 		}

 		// NOTE: there can be no invalid transactions from this point.
@@ -167,13 +168,14 @@ impl<'a> Executive<'a> {
 				let new_address = contract_address(&sender, &nonce);
 				let params = ActionParams {
 					code_address: new_address.clone(),
+					code_hash: t.data.sha3(),
 					address: new_address,
 					sender: sender.clone(),
 					origin: sender.clone(),
 					gas: init_gas,
 					gas_price: t.gas_price,
 					value: ActionValue::Transfer(t.value),
-					code: Some(t.data.clone()),
+					code: Some(Arc::new(t.data.clone())),
 					data: None,
 					call_type: CallType::None,
 				};
@@ -189,6 +191,7 @@ impl<'a> Executive<'a> {
 					gas_price: t.gas_price,
 					value: ActionValue::Transfer(t.value),
 					code: self.state.code(address),
+					code_hash: self.state.code_hash(address),
 					data: Some(t.data.clone()),
 					call_type: CallType::Call,
 				};
@@ -210,8 +213,11 @@ impl<'a> Executive<'a> {
 		tracer: &mut T,
 		vm_tracer: &mut V
 	) -> evm::Result<U256> where T: Tracer, V: VMTracer {
+
+		let depth_threshold = ::io::LOCAL_STACK_SIZE.with(|sz| sz.get() / STACK_SIZE_PER_DEPTH);
+
 		// Ordinary execution - keep VM in same thread
-		if (self.depth + 1) % MAX_VM_DEPTH_FOR_THREAD != 0 {
+		if (self.depth + 1) % depth_threshold != 0 {
 			let vm_factory = self.vm_factory;
 			let mut ext = self.as_externalities(OriginInfo::from(&params), unconfirmed_substate, output_policy, tracer, vm_tracer);
 			trace!(target: "executive", "ext.schedule.have_delegate_call: {}", ext.schedule().have_delegate_call);
@@ -263,7 +269,7 @@ impl<'a> Executive<'a> {
 			let cost = self.engine.cost_of_builtin(&params.code_address, data);
 			if cost <= params.gas {
 				self.engine.execute_builtin(&params.code_address, data, &mut output);
-				self.state.clear_snapshot();
+				self.state.discard_snapshot();

 				// trace only top level calls to builtins to avoid DDoS attacks
 				if self.depth == 0 {
@@ -283,7 +289,7 @@ impl<'a> Executive<'a> {
 				Ok(params.gas - cost)
 			} else {
 				// just drain the whole gas
-				self.state.revert_snapshot();
+				self.state.revert_to_snapshot();

 				tracer.trace_failed_call(trace_info, vec![]);

@@ -329,7 +335,7 @@ impl<'a> Executive<'a> {
 				res
 			} else {
 				// otherwise it's just a basic transaction, only do tracing, if necessary.
-				self.state.clear_snapshot();
+				self.state.discard_snapshot();

 				tracer.trace_call(trace_info, U256::zero(), trace_output, vec![]);
 				Ok(params.gas)
@@ -411,7 +417,7 @@ impl<'a> Executive<'a> {

 		// real ammount to refund
 		let gas_left_prerefund = match result { Ok(x) => x, _ => 0.into() };
-		let refunded = cmp::min(refunds_bound, (t.gas - gas_left_prerefund) / U256::from(2));
+		let refunded = cmp::min(refunds_bound, (t.gas - gas_left_prerefund) >> 1);
 		let gas_left = gas_left_prerefund + refunded;

 		let gas_used = t.gas - gas_left;
@@ -471,10 +477,10 @@ impl<'a> Executive<'a> {
 				| Err(evm::Error::BadInstruction {.. })
 				| Err(evm::Error::StackUnderflow {..})
 				| Err(evm::Error::OutOfStack {..}) => {
-					self.state.revert_snapshot();
+					self.state.revert_to_snapshot();
 			},
 			Ok(_) | Err(evm::Error::Internal) => {
-				self.state.clear_snapshot();
+				self.state.discard_snapshot();
 				substate.accrue(un_substate);
 			}
 		}
@@ -510,7 +516,7 @@ mod tests {
 		params.address = address.clone();
 		params.sender = sender.clone();
 		params.gas = U256::from(100_000);
-		params.code = Some("3331600055".from_hex().unwrap());
+		params.code = Some(Arc::new("3331600055".from_hex().unwrap()));
 		params.value = ActionValue::Transfer(U256::from(0x7));
 		let mut state_result = get_temp_state();
 		let mut state = state_result.reference_mut();
@@ -569,7 +575,7 @@ mod tests {
 		params.sender = sender.clone();
 		params.origin = sender.clone();
 		params.gas = U256::from(100_000);
-		params.code = Some(code.clone());
+		params.code = Some(Arc::new(code));
 		params.value = ActionValue::Transfer(U256::from(100));
 		let mut state_result = get_temp_state();
 		let mut state = state_result.reference_mut();
@@ -624,7 +630,7 @@ mod tests {
 		params.sender = sender.clone();
 		params.origin = sender.clone();
 		params.gas = U256::from(100_000);
-		params.code = Some(code.clone());
+		params.code = Some(Arc::new(code));
 		params.value = ActionValue::Transfer(U256::from(100));
 		params.call_type = CallType::Call;
 		let mut state_result = get_temp_state();
@@ -734,7 +740,7 @@ mod tests {
 		params.sender = sender.clone();
 		params.origin = sender.clone();
 		params.gas = U256::from(100_000);
-		params.code = Some(code.clone());
+		params.code = Some(Arc::new(code));
 		params.value = ActionValue::Transfer(100.into());
 		let mut state_result = get_temp_state();
 		let mut state = state_result.reference_mut();
@@ -822,7 +828,7 @@ mod tests {
 		params.sender = sender.clone();
 		params.origin = sender.clone();
 		params.gas = U256::from(100_000);
-		params.code = Some(code.clone());
+		params.code = Some(Arc::new(code));
 		params.value = ActionValue::Transfer(U256::from(100));
 		let mut state_result = get_temp_state();
 		let mut state = state_result.reference_mut();
@@ -874,7 +880,7 @@ mod tests {
 		params.sender = sender.clone();
 		params.origin = sender.clone();
 		params.gas = U256::from(100_000);
-		params.code = Some(code.clone());
+		params.code = Some(Arc::new(code));
 		params.value = ActionValue::Transfer(U256::from(100));
 		let mut state_result = get_temp_state();
 		let mut state = state_result.reference_mut();
@@ -931,7 +937,7 @@ mod tests {
 		params.address = address_a.clone();
 		params.sender = sender.clone();
 		params.gas = U256::from(100_000);
-		params.code = Some(code_a.clone());
+		params.code = Some(Arc::new(code_a.clone()));
 		params.value = ActionValue::Transfer(U256::from(100_000));

 		let mut state_result = get_temp_state();
@@ -981,10 +987,10 @@ mod tests {
 		let mut params = ActionParams::default();
 		params.address = address.clone();
 		params.gas = U256::from(100_000);
-		params.code = Some(code.clone());
+		params.code = Some(Arc::new(code.clone()));
 		let mut state_result = get_temp_state();
 		let mut state = state_result.reference_mut();
-		state.init_code(&address, code.clone());
+		state.init_code(&address, code);
 		let info = EnvInfo::default();
 		let engine = TestEngine::new(0);
 		let mut substate = Substate::new();
@@ -1182,7 +1188,7 @@ mod tests {
 		params.sender = sender.clone();
 		params.origin = sender.clone();
 		params.gas = U256::from(0x0186a0);
-		params.code = Some(code.clone());
+		params.code = Some(Arc::new(code));
 		params.value = ActionValue::Transfer(U256::from_str("0de0b6b3a7640000").unwrap());
 		let mut state_result = get_temp_state();
 		let mut state = state_result.reference_mut();
--- a/ethcore/src/externalities.rs
+++ b/ethcore/src/externalities.rs
@@ -147,7 +147,8 @@ impl<'a, T, V> Ext for Externalities<'a, T, V> where T: 'a + Tracer, V: 'a + VMT
 			gas: *gas,
 			gas_price: self.origin_info.gas_price,
 			value: ActionValue::Transfer(*value),
-			code: Some(code.to_vec()),
+			code: Some(Arc::new(code.to_vec())),
+			code_hash: code.sha3(),
 			data: None,
 			call_type: CallType::None,
 		};
@@ -186,6 +187,7 @@ impl<'a, T, V> Ext for Externalities<'a, T, V> where T: 'a + Tracer, V: 'a + VMT
 			gas: *gas,
 			gas_price: self.origin_info.gas_price,
 			code: self.state.code(code_address),
+			code_hash: self.state.code_hash(code_address),
 			data: Some(data.to_vec()),
 			call_type: call_type,
 		};
@@ -202,8 +204,12 @@ impl<'a, T, V> Ext for Externalities<'a, T, V> where T: 'a + Tracer, V: 'a + VMT
 		}
 	}

-	fn extcode(&self, address: &Address) -> Bytes {
-		self.state.code(address).unwrap_or_else(|| vec![])
+	fn extcode(&self, address: &Address) -> Arc<Bytes> {
+		self.state.code(address).unwrap_or_else(|| Arc::new(vec![]))
+	}
+
+	fn extcode_len(&self, address: &Address) -> u64 {
+		self.state.code_size(address).unwrap_or(0)
 	}

 	#[cfg_attr(feature="dev", allow(match_ref_pats))]
--- a/ethcore/src/json_tests/executive.rs
+++ b/ethcore/src/json_tests/executive.rs
@@ -128,10 +128,14 @@ impl<'a, T, V> Ext for TestExt<'a, T, V> where T: Tracer, V: VMTracer {
 		MessageCallResult::Success(*gas)
 	}

-	fn extcode(&self, address: &Address) -> Bytes  {
+	fn extcode(&self, address: &Address) -> Arc<Bytes>  {
 		self.ext.extcode(address)
 	}

+	fn extcode_len(&self, address: &Address) -> u64  {
+		self.ext.extcode_len(address)
+	}
+
 	fn log(&mut self, topics: Vec<H256>, data: &[u8]) {
 		self.ext.log(topics, data)
 	}
@@ -229,7 +233,7 @@ fn do_json_test_for(vm_type: &VMType, json_data: &[u8]) -> Vec<String> {
 				for (address, account) in vm.post_state.unwrap().into_iter() {
 					let address = address.into();
 					let code: Vec<u8> = account.code.into();
-					fail_unless(state.code(&address).unwrap_or_else(Vec::new) == code, "code is incorrect");
+					fail_unless(state.code(&address).as_ref().map_or_else(|| code.is_empty(), |c| &**c == &code), "code is incorrect");
 					fail_unless(state.balance(&address) == account.balance.into(), "balance is incorrect");
 					fail_unless(state.nonce(&address) == account.nonce.into(), "nonce is incorrect");
 					account.storage.into_iter().foreach(|(k, v)| {
--- a/ethcore/src/lib.rs
+++ b/ethcore/src/lib.rs
@@ -100,8 +100,12 @@ extern crate ethcore_ipc_nano as nanoipc;
 extern crate ethcore_devtools as devtools;
 extern crate rand;
 extern crate bit_set;
+extern crate lru_cache;
+extern crate bloomfilter;
+extern crate byteorder;

-#[cfg(feature = "jit" )] extern crate evmjit;
+#[cfg(feature = "jit" )]
+extern crate evmjit;

 pub mod account_provider;
 pub mod engines;
@@ -130,6 +134,7 @@ mod basic_types;
 mod env_info;
 mod pod_account;
 mod state;
+mod state_db;
 mod account;
 mod account_db;
 mod builtin;
--- a/ethcore/src/migrations/account_bloom.rs
+++ b/ethcore/src/migrations/account_bloom.rs
@@ -0,0 +1,104 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Bloom upgrade
+
+use client::{DB_COL_EXTRA, DB_COL_HEADERS, DB_NO_OF_COLUMNS, DB_COL_STATE, DB_COL_ACCOUNT_BLOOM};
+use state_db::{ACCOUNT_BLOOM_SPACE, DEFAULT_ACCOUNT_PRESET, StateDB, ACCOUNT_BLOOM_HASHCOUNT_KEY};
+use util::trie::TrieDB;
+use views::HeaderView;
+use bloomfilter::Bloom;
+use util::migration::Error;
+use util::journaldb;
+use util::{H256, FixedHash, BytesConvertable};
+use util::{Database, DatabaseConfig, DBTransaction, CompactionProfile};
+use std::path::Path;
+
+fn check_bloom_exists(db: &Database) -> bool {
+	let hash_count_entry = db.get(DB_COL_ACCOUNT_BLOOM, ACCOUNT_BLOOM_HASHCOUNT_KEY)
+		.expect("Low-level database error");
+
+	hash_count_entry.is_some()
+}
+
+/// Account bloom upgrade routine. If bloom already present, does nothing.
+/// If database empty (no best block), does nothing.
+/// Can be called on upgraded database with no issues (will do nothing).
+pub fn upgrade_account_bloom(db_path: &Path) -> Result<(), Error> {
+	let path = try!(db_path.to_str().ok_or(Error::MigrationImpossible));
+	trace!(target: "migration", "Account bloom upgrade at {:?}", db_path);
+
+	let source = try!(Database::open(&DatabaseConfig {
+		max_open_files: 64,
+		cache_size: None,
+		compaction: CompactionProfile::default(),
+		columns: DB_NO_OF_COLUMNS,
+		wal: true,
+	}, path));
+
+	let best_block_hash = match try!(source.get(DB_COL_EXTRA, b"best")) {
+		// no migration needed
+		None => {
+			trace!(target: "migration", "No best block hash, skipping");
+			return Ok(());
+		},
+		Some(hash) => hash,
+	};
+	let best_block_header = match try!(source.get(DB_COL_HEADERS, &best_block_hash)) {
+		// no best block, nothing to do
+		None => {
+			trace!(target: "migration", "No best block header, skipping");
+			return Ok(())
+		},
+		Some(x) => x,
+	};
+	let state_root = HeaderView::new(&best_block_header).state_root();
+
+	if check_bloom_exists(&source) {
+		// bloom already exists, nothing to do
+		trace!(target: "migration", "Bloom already present, skipping");
+		return Ok(())
+	}
+
+	println!("Adding accounts bloom (one-time upgrade)");
+	let db = ::std::sync::Arc::new(source);
+	let bloom_journal = {
+		let mut bloom = Bloom::new(ACCOUNT_BLOOM_SPACE, DEFAULT_ACCOUNT_PRESET);
+		// no difference what algorithm is passed, since there will be no writes
+		let state_db = journaldb::new(
+			db.clone(),
+			journaldb::Algorithm::OverlayRecent,
+			DB_COL_STATE);
+		let account_trie = try!(TrieDB::new(state_db.as_hashdb(), &state_root).map_err(|e| Error::Custom(format!("Cannot open trie: {:?}", e))));
+		for (ref account_key, _) in account_trie.iter() {
+			let account_key_hash = H256::from_slice(&account_key);
+			bloom.set(account_key_hash.as_slice());
+		}
+
+		bloom.drain_journal()
+	};
+
+	trace!(target: "migration", "Generated {} bloom updates", bloom_journal.entries.len());
+
+	let batch = DBTransaction::new(&db);
+	try!(StateDB::commit_bloom(&batch, bloom_journal).map_err(|_| Error::Custom("Failed to commit bloom".to_owned())));
+	try!(db.write(batch));
+
+	trace!(target: "migration", "Finished bloom update");
+
+
+	Ok(())
+}
--- a/ethcore/src/migrations/mod.rs
+++ b/ethcore/src/migrations/mod.rs
@@ -23,3 +23,9 @@ pub mod extras;
 mod v9;
 pub use self::v9::ToV9;
 pub use self::v9::Extract;
+
+mod account_bloom;
+pub use self::account_bloom::upgrade_account_bloom;
+
+mod v10;
+pub use self::v10::ToV10;
--- a/ethcore/src/migrations/v10.rs
+++ b/ethcore/src/migrations/v10.rs
@@ -0,0 +1,35 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+//! This migration compresses the state db.
+
+use util::migration::SimpleMigration;
+
+/// Compressing migration.
+#[derive(Default)]
+pub struct ToV10;
+
+impl SimpleMigration for ToV10 {
+	fn version(&self) -> u32 {
+		10
+	}
+
+	fn columns(&self) -> Option<u32> { Some(6) }
+
+	fn simple_migrate(&mut self, key: Vec<u8>, value: Vec<u8>) -> Option<(Vec<u8>, Vec<u8>)> {
+		Some((key, value))
+	}
+}
--- a/ethcore/src/miner/miner.rs
+++ b/ethcore/src/miner/miner.rs
@@ -25,12 +25,13 @@ use state::State;
 use client::{MiningBlockChainClient, Executive, Executed, EnvInfo, TransactOptions, BlockID, CallAnalytics};
 use executive::contract_address;
 use block::{ClosedBlock, IsBlock, Block};
+use header::BlockNumber;
 use error::*;
 use transaction::{Action, SignedTransaction};
 use receipt::{Receipt, RichReceipt};
 use spec::Spec;
 use engines::Engine;
-use miner::{MinerService, MinerStatus, TransactionQueue, AccountDetails, TransactionOrigin};
+use miner::{MinerService, MinerStatus, TransactionQueue, PrioritizationStrategy, AccountDetails, TransactionOrigin};
 use miner::work_notify::WorkPoster;
 use client::TransactionImportResult;
 use miner::price_info::PriceInfo;
@@ -64,6 +65,8 @@ pub struct MinerOptions {
 	pub tx_gas_limit: U256,
 	/// Maximum size of the transaction queue.
 	pub tx_queue_size: usize,
+	/// Strategy to use for prioritizing transactions in the queue.
+	pub tx_queue_strategy: PrioritizationStrategy,
 	/// Whether we should fallback to providing all the queue's transactions or just pending.
 	pub pending_set: PendingSet,
 	/// How many historical work packages can we store before running out?
@@ -80,7 +83,8 @@ impl Default for MinerOptions {
 			reseal_on_external_tx: false,
 			reseal_on_own_tx: true,
 			tx_gas_limit: !U256::zero(),
-			tx_queue_size: 1024,
+			tx_queue_size: 2048,
+			tx_queue_strategy: PrioritizationStrategy::GasFactorAndGasPrice,
 			pending_set: PendingSet::AlwaysQueue,
 			reseal_min_period: Duration::from_secs(2),
 			work_queue_size: 20,
@@ -188,7 +192,7 @@ impl Miner {
 	/// Creates new instance of miner without accounts, but with given spec.
 	pub fn with_spec(spec: &Spec) -> Miner {
 		Miner {
-			transaction_queue: Arc::new(Mutex::new(TransactionQueue::new())),
+			transaction_queue: Arc::new(Mutex::new(TransactionQueue::default())),
 			options: Default::default(),
 			next_allowed_reseal: Mutex::new(Instant::now()),
 			sealing_block_last_request: Mutex::new(0),
@@ -206,7 +210,9 @@ impl Miner {
 	/// Creates new instance of miner
 	pub fn new(options: MinerOptions, gas_pricer: GasPricer, spec: &Spec, accounts: Option<Arc<AccountProvider>>) -> Arc<Miner> {
 		let work_poster = if !options.new_work_notify.is_empty() { Some(WorkPoster::new(&options.new_work_notify)) } else { None };
-		let txq = Arc::new(Mutex::new(TransactionQueue::with_limits(options.tx_queue_size, options.tx_gas_limit)));
+		let txq = Arc::new(Mutex::new(TransactionQueue::with_limits(
+			options.tx_queue_strategy, options.tx_queue_size, !U256::zero(), options.tx_gas_limit
+		)));
 		Arc::new(Miner {
 			transaction_queue: txq,
 			next_allowed_reseal: Mutex::new(Instant::now()),
@@ -243,6 +249,7 @@ impl Miner {
 	fn prepare_sealing(&self, chain: &MiningBlockChainClient) {
 		trace!(target: "miner", "prepare_sealing: entering");

+		let _timer = PerfTimer::new("prepare_sealing");
 		{
 			trace!(target: "miner", "recalibrating...");
 			let txq = self.transaction_queue.clone();
@@ -286,6 +293,7 @@ impl Miner {
 		};

 		let mut invalid_transactions = HashSet::new();
+		let mut transactions_to_penalize = HashSet::new();
 		let block_number = open_block.block().fields().header.number();
 		// TODO: push new uncles, too.
 		for tx in transactions {
@@ -293,6 +301,12 @@ impl Miner {
 			match open_block.push_transaction(tx, None) {
 				Err(Error::Execution(ExecutionError::BlockGasLimitReached { gas_limit, gas_used, gas })) => {
 					debug!(target: "miner", "Skipping adding transaction to block because of gas limit: {:?} (limit: {:?}, used: {:?}, gas: {:?})", hash, gas_limit, gas_used, gas);
+
+					// Penalize transaction if it's above current gas limit
+					if gas > gas_limit {
+						transactions_to_penalize.insert(hash);
+					}
+
 					// Exit early if gas left is smaller then min_tx_gas
 					let min_tx_gas: U256 = 21000.into();	// TODO: figure this out properly.
 					if gas_limit - gas_used < min_tx_gas {
@@ -328,6 +342,9 @@ impl Miner {
 			for hash in invalid_transactions.into_iter() {
 				queue.remove_invalid(&hash, &fetch_account);
 			}
+			for hash in transactions_to_penalize {
+				queue.penalize(&hash);
+			}
 		}

 		if !block.transactions().is_empty() {
@@ -385,6 +402,8 @@ impl Miner {
 		let gas_limit = HeaderView::new(&chain.best_block_header()).gas_limit();
 		let mut queue = self.transaction_queue.lock();
 		queue.set_gas_limit(gas_limit);
+		// Set total qx queue gas limit to be 2x the block gas limit.
+		queue.set_total_gas_limit(gas_limit << 1);
 	}

 	/// Returns true if we had to prepare new pending block
@@ -434,6 +453,21 @@ impl Miner {

 	/// Are we allowed to do a non-mandatory reseal?
 	fn tx_reseal_allowed(&self) -> bool { Instant::now() > *self.next_allowed_reseal.lock() }
+
+	fn from_pending_block<H, F, G>(&self, latest_block_number: BlockNumber, from_chain: F, map_block: G) -> H
+		where F: Fn() -> H, G: Fn(&ClosedBlock) -> H {
+		let sealing_work = self.sealing_work.lock();
+		sealing_work.queue.peek_last_ref().map_or_else(
+			|| from_chain(),
+			|b| {
+				if b.block().header().number() > latest_block_number {
+					map_block(b)
+				} else {
+					from_chain()
+				}
+			}
+		)
+	}
 }

 const SEALING_TIMEOUT_IN_BLOCKS : u64 = 5;
@@ -506,29 +540,35 @@ impl MinerService for Miner {
 	}

 	fn balance(&self, chain: &MiningBlockChainClient, address: &Address) -> U256 {
-		let sealing_work = self.sealing_work.lock();
-		sealing_work.queue.peek_last_ref().map_or_else(
+		self.from_pending_block(
+			chain.chain_info().best_block_number,
 			|| chain.latest_balance(address),
 			|b| b.block().fields().state.balance(address)
 		)
 	}

 	fn storage_at(&self, chain: &MiningBlockChainClient, address: &Address, position: &H256) -> H256 {
-		let sealing_work = self.sealing_work.lock();
-		sealing_work.queue.peek_last_ref().map_or_else(
+		self.from_pending_block(
+			chain.chain_info().best_block_number,
 			|| chain.latest_storage_at(address, position),
 			|b| b.block().fields().state.storage_at(address, position)
 		)
 	}

 	fn nonce(&self, chain: &MiningBlockChainClient, address: &Address) -> U256 {
-		let sealing_work = self.sealing_work.lock();
-		sealing_work.queue.peek_last_ref().map_or_else(|| chain.latest_nonce(address), |b| b.block().fields().state.nonce(address))
+		self.from_pending_block(
+			chain.chain_info().best_block_number,
+			|| chain.latest_nonce(address),
+			|b| b.block().fields().state.nonce(address)
+		)
 	}

 	fn code(&self, chain: &MiningBlockChainClient, address: &Address) -> Option<Bytes> {
-		let sealing_work = self.sealing_work.lock();
-		sealing_work.queue.peek_last_ref().map_or_else(|| chain.latest_code(address), |b| b.block().fields().state.code(address))
+		self.from_pending_block(
+			chain.chain_info().best_block_number,
+			|| chain.latest_code(address),
+			|b| b.block().fields().state.code(address).map(|c| (*c).clone())
+		)
 	}

 	fn set_author(&self, author: Address) {
@@ -673,50 +713,74 @@ impl MinerService for Miner {
 		queue.top_transactions()
 	}

-	fn pending_transactions(&self) -> Vec<SignedTransaction> {
+	fn pending_transactions(&self, best_block: BlockNumber) -> Vec<SignedTransaction> {
 		let queue = self.transaction_queue.lock();
-		let sw = self.sealing_work.lock();
-		// TODO: should only use the sealing_work when it's current (it could be an old block)
-		let sealing_set = match sw.enabled {
-			true => sw.queue.peek_last_ref(),
-			false => None,
-		};
-		match (&self.options.pending_set, sealing_set) {
-			(&PendingSet::AlwaysQueue, _) | (&PendingSet::SealingOrElseQueue, None) => queue.top_transactions(),
-			(_, sealing) => sealing.map_or_else(Vec::new, |s| s.transactions().to_owned()),
+		match self.options.pending_set {
+			PendingSet::AlwaysQueue => queue.top_transactions(),
+			PendingSet::SealingOrElseQueue => {
+				self.from_pending_block(
+					best_block,
+					|| queue.top_transactions(),
+					|sealing| sealing.transactions().to_owned()
+				)
+			},
+			PendingSet::AlwaysSealing => {
+				self.from_pending_block(
+					best_block,
+					|| vec![],
+					|sealing| sealing.transactions().to_owned()
+				)
+			},
 		}
 	}

-	fn pending_transactions_hashes(&self) -> Vec<H256> {
+	fn pending_transactions_hashes(&self, best_block: BlockNumber) -> Vec<H256> {
 		let queue = self.transaction_queue.lock();
-		let sw = self.sealing_work.lock();
-		let sealing_set = match sw.enabled {
-			true => sw.queue.peek_last_ref(),
-			false => None,
-		};
-		match (&self.options.pending_set, sealing_set) {
-			(&PendingSet::AlwaysQueue, _) | (&PendingSet::SealingOrElseQueue, None) => queue.pending_hashes(),
-			(_, sealing) => sealing.map_or_else(Vec::new, |s| s.transactions().iter().map(|t| t.hash()).collect()),
+		match self.options.pending_set {
+			PendingSet::AlwaysQueue => queue.pending_hashes(),
+			PendingSet::SealingOrElseQueue => {
+				self.from_pending_block(
+					best_block,
+					|| queue.pending_hashes(),
+					|sealing| sealing.transactions().iter().map(|t| t.hash()).collect()
+				)
+			},
+			PendingSet::AlwaysSealing => {
+				self.from_pending_block(
+					best_block,
+					|| vec![],
+					|sealing| sealing.transactions().iter().map(|t| t.hash()).collect()
+				)
+			},
 		}
 	}

-	fn transaction(&self, hash: &H256) -> Option<SignedTransaction> {
+	fn transaction(&self, best_block: BlockNumber, hash: &H256) -> Option<SignedTransaction> {
 		let queue = self.transaction_queue.lock();
-		let sw = self.sealing_work.lock();
-		let sealing_set = match sw.enabled {
-			true => sw.queue.peek_last_ref(),
-			false => None,
-		};
-		match (&self.options.pending_set, sealing_set) {
-			(&PendingSet::AlwaysQueue, _) | (&PendingSet::SealingOrElseQueue, None) => queue.find(hash),
-			(_, sealing) => sealing.and_then(|s| s.transactions().iter().find(|t| &t.hash() == hash).cloned()),
+		match self.options.pending_set {
+			PendingSet::AlwaysQueue => queue.find(hash),
+			PendingSet::SealingOrElseQueue => {
+				self.from_pending_block(
+					best_block,
+					|| queue.find(hash),
+					|sealing| sealing.transactions().iter().find(|t| &t.hash() == hash).cloned()
+				)
+			},
+			PendingSet::AlwaysSealing => {
+				self.from_pending_block(
+					best_block,
+					|| None,
+					|sealing| sealing.transactions().iter().find(|t| &t.hash() == hash).cloned()
+				)
+			},
 		}
 	}

-	fn pending_receipt(&self, hash: &H256) -> Option<RichReceipt> {
-		let sealing_work = self.sealing_work.lock();
-		match (sealing_work.enabled, sealing_work.queue.peek_last_ref()) {
-			(true, Some(pending)) => {
+	fn pending_receipt(&self, best_block: BlockNumber, hash: &H256) -> Option<RichReceipt> {
+		self.from_pending_block(
+			best_block,
+			|| None,
+			|pending| {
 				let txs = pending.transactions();
 				txs.iter()
 					.map(|t| t.hash())
@@ -737,15 +801,15 @@ impl MinerService for Miner {
 							logs: receipt.logs.clone(),
 						}
 					})
-			},
-			_ => None
-		}
+			}
+		)
 	}

-	fn pending_receipts(&self) -> BTreeMap<H256, Receipt> {
-		let sealing_work = self.sealing_work.lock();
-		match (sealing_work.enabled, sealing_work.queue.peek_last_ref()) {
-			(true, Some(pending)) => {
+	fn pending_receipts(&self, best_block: BlockNumber) -> BTreeMap<H256, Receipt> {
+		self.from_pending_block(
+			best_block,
+			|| BTreeMap::new(),
+			|pending| {
 				let hashes = pending.transactions()
 					.iter()
 					.map(|t| t.hash());
@@ -753,9 +817,8 @@ impl MinerService for Miner {
 				let receipts = pending.receipts().iter().cloned();

 				hashes.zip(receipts).collect()
-			},
-			_ => BTreeMap::new()
-		}
+			}
+		)
 	}

 	fn last_nonce(&self, address: &Address) -> Option<U256> {
@@ -869,7 +932,7 @@ impl MinerService for Miner {
 			out_of_chain.for_each(|txs| {
 				let mut transaction_queue = self.transaction_queue.lock();
 				let _ = self.add_transactions_to_queue(
-					chain, txs, TransactionOrigin::External, &mut transaction_queue
+					chain, txs, TransactionOrigin::RetractedBlock, &mut transaction_queue
 				);
 			});
 		}
@@ -908,7 +971,7 @@ impl MinerService for Miner {
 mod tests {

 	use std::time::Duration;
-	use super::super::MinerService;
+	use super::super::{MinerService, PrioritizationStrategy};
 	use super::*;
 	use util::*;
 	use client::{TestBlockChainClient, EachBlockWith};
@@ -959,6 +1022,7 @@ mod tests {
 				reseal_min_period: Duration::from_secs(5),
 				tx_gas_limit: !U256::zero(),
 				tx_queue_size: 1024,
+				tx_queue_strategy: PrioritizationStrategy::GasFactorAndGasPrice,
 				pending_set: PendingSet::AlwaysSealing,
 				work_queue_size: 5,
 				enable_resubmission: true,
@@ -985,20 +1049,48 @@ mod tests {
 				nonce: U256::zero(),
 			}.sign(keypair.secret())
 		};
-
+		let best_block = 0;
 		// when
 		let res = miner.import_own_transaction(&client, transaction);

 		// then
 		assert_eq!(res.unwrap(), TransactionImportResult::Current);
 		assert_eq!(miner.all_transactions().len(), 1);
-		assert_eq!(miner.pending_transactions().len(), 1);
-		assert_eq!(miner.pending_transactions_hashes().len(), 1);
-		assert_eq!(miner.pending_receipts().len(), 1);
+		assert_eq!(miner.pending_transactions(best_block).len(), 1);
+		assert_eq!(miner.pending_transactions_hashes(best_block).len(), 1);
+		assert_eq!(miner.pending_receipts(best_block).len(), 1);
 		// This method will let us know if pending block was created (before calling that method)
 		assert_eq!(miner.enable_and_prepare_sealing(&client), false);
 	}

+	#[test]
+	fn should_not_use_pending_block_if_best_block_is_higher() {
+		// given
+		let client = TestBlockChainClient::default();
+		let miner = miner();
+		let transaction = {
+			let keypair = KeyPair::create().unwrap();
+			Transaction {
+				action: Action::Create,
+				value: U256::zero(),
+				data: "3331600055".from_hex().unwrap(),
+				gas: U256::from(100_000),
+				gas_price: U256::zero(),
+				nonce: U256::zero(),
+			}.sign(keypair.secret())
+		};
+		let best_block = 10;
+		// when
+		let res = miner.import_own_transaction(&client, transaction);
+
+		// then
+		assert_eq!(res.unwrap(), TransactionImportResult::Current);
+		assert_eq!(miner.all_transactions().len(), 1);
+		assert_eq!(miner.pending_transactions(best_block).len(), 0);
+		assert_eq!(miner.pending_transactions_hashes(best_block).len(), 0);
+		assert_eq!(miner.pending_receipts(best_block).len(), 0);
+	}
+
 	#[test]
 	fn should_import_external_transaction() {
 		// given
@@ -1015,16 +1107,16 @@ mod tests {
 				nonce: U256::zero(),
 			}.sign(keypair.secret())
 		};
-
+		let best_block = 0;
 		// when
 		let res = miner.import_external_transactions(&client, vec![transaction]).pop().unwrap();

 		// then
 		assert_eq!(res.unwrap(), TransactionImportResult::Current);
 		assert_eq!(miner.all_transactions().len(), 1);
-		assert_eq!(miner.pending_transactions_hashes().len(), 0);
-		assert_eq!(miner.pending_transactions().len(), 0);
-		assert_eq!(miner.pending_receipts().len(), 0);
+		assert_eq!(miner.pending_transactions_hashes(best_block).len(), 0);
+		assert_eq!(miner.pending_transactions(best_block).len(), 0);
+		assert_eq!(miner.pending_receipts(best_block).len(), 0);
 		// This method will let us know if pending block was created (before calling that method)
 		assert_eq!(miner.enable_and_prepare_sealing(&client), true);
 	}
--- a/ethcore/src/miner/mod.rs
+++ b/ethcore/src/miner/mod.rs
@@ -47,7 +47,7 @@ mod transaction_queue;
 mod work_notify;
 mod price_info;

-pub use self::transaction_queue::{TransactionQueue, AccountDetails, TransactionOrigin};
+pub use self::transaction_queue::{TransactionQueue, PrioritizationStrategy, AccountDetails, TransactionOrigin};
 pub use self::miner::{Miner, MinerOptions, PendingSet, GasPricer, GasPriceCalibratorOptions};
 pub use self::external::{ExternalMiner, ExternalMinerService};
 pub use client::TransactionImportResult;
@@ -56,6 +56,7 @@ use std::collections::BTreeMap;
 use util::{H256, U256, Address, Bytes};
 use client::{MiningBlockChainClient, Executed, CallAnalytics};
 use block::ClosedBlock;
+use header::BlockNumber;
 use receipt::{RichReceipt, Receipt};
 use error::{Error, CallError};
 use transaction::SignedTransaction;
@@ -115,7 +116,7 @@ pub trait MinerService : Send + Sync {
 		Result<TransactionImportResult, Error>;

 	/// Returns hashes of transactions currently in pending
-	fn pending_transactions_hashes(&self) -> Vec<H256>;
+	fn pending_transactions_hashes(&self, best_block: BlockNumber) -> Vec<H256>;

 	/// Removes all transactions from the queue and restart mining operation.
 	fn clear_and_reset(&self, chain: &MiningBlockChainClient);
@@ -135,19 +136,19 @@ pub trait MinerService : Send + Sync {
 		where F: FnOnce(&ClosedBlock) -> T, Self: Sized;

 	/// Query pending transactions for hash.
-	fn transaction(&self, hash: &H256) -> Option<SignedTransaction>;
+	fn transaction(&self, best_block: BlockNumber, hash: &H256) -> Option<SignedTransaction>;

 	/// Get a list of all transactions.
 	fn all_transactions(&self) -> Vec<SignedTransaction>;

 	/// Get a list of all pending transactions.
-	fn pending_transactions(&self) -> Vec<SignedTransaction>;
+	fn pending_transactions(&self, best_block: BlockNumber) -> Vec<SignedTransaction>;

 	/// Get a list of all pending receipts.
-	fn pending_receipts(&self) -> BTreeMap<H256, Receipt>;
+	fn pending_receipts(&self, best_block: BlockNumber) -> BTreeMap<H256, Receipt>;

 	/// Get a particular reciept.
-	fn pending_receipt(&self, hash: &H256) -> Option<RichReceipt>;
+	fn pending_receipt(&self, best_block: BlockNumber, hash: &H256) -> Option<RichReceipt>;

 	/// Returns highest transaction nonce for given address.
 	fn last_nonce(&self, address: &Address) -> Option<U256>;
--- a/ethcore/src/miner/transaction_queue.rs
+++ b/ethcore/src/miner/transaction_queue.rs
--- a/ethcore/src/pod_account.rs
+++ b/ethcore/src/pod_account.rs
@@ -47,7 +47,7 @@ impl PodAccount {
 		PodAccount {
 			balance: *acc.balance(),
 			nonce: *acc.nonce(),
-			storage: acc.storage_overlay().iter().fold(BTreeMap::new(), |mut m, (k, &(_, ref v))| {m.insert(k.clone(), v.clone()); m}),
+			storage: acc.storage_changes().iter().fold(BTreeMap::new(), |mut m, (k, v)| {m.insert(k.clone(), v.clone()); m}),
 			code: acc.code().map(|x| x.to_vec()),
 		}
 	}
--- a/ethcore/src/snapshot/account.rs
+++ b/ethcore/src/snapshot/account.rs
@@ -143,7 +143,7 @@ impl Account {
 #[cfg(test)]
 mod tests {
 	use account_db::{AccountDB, AccountDBMut};
-	use tests::helpers::get_temp_journal_db;
+	use tests::helpers::get_temp_state_db;
 	use snapshot::tests::helpers::fill_storage;

 	use util::{SHA3_NULL_RLP, SHA3_EMPTY};
@@ -154,8 +154,7 @@ mod tests {

 	#[test]
 	fn encoding_basic() {
-		let mut db = get_temp_journal_db();
-		let mut db = &mut **db;
+		let mut db = get_temp_state_db();
 		let addr = Address::random();

 		let account = Account {
@@ -175,8 +174,7 @@ mod tests {

 	#[test]
 	fn encoding_storage() {
-		let mut db = get_temp_journal_db();
-		let mut db = &mut **db;
+		let mut db = get_temp_state_db();
 		let addr = Address::random();

 		let account = {
@@ -198,4 +196,4 @@ mod tests {
 		let fat_rlp = UntrustedRlp::new(&fat_rlp);
 		assert_eq!(Account::from_fat_rlp(&mut AccountDBMut::new(db.as_hashdb_mut(), &addr), fat_rlp).unwrap(), account);
 	}
-}
+}
--- a/ethcore/src/snapshot/mod.rs
+++ b/ethcore/src/snapshot/mod.rs
@@ -25,8 +25,9 @@ use blockchain::{BlockChain, BlockProvider};
 use engines::Engine;
 use ids::BlockID;
 use views::BlockView;
+use super::state_db::StateDB;

-use util::{Bytes, Hashable, HashDB, snappy, TrieDB, TrieDBMut, TrieMut};
+use util::{Bytes, Hashable, HashDB, snappy, TrieDB, TrieDBMut, TrieMut, BytesConvertable};
 use util::Mutex;
 use util::hash::{FixedHash, H256};
 use util::journaldb::{self, Algorithm, JournalDB};
@@ -453,7 +454,7 @@ impl StateRebuilder {
 			Ok::<_, ::error::Error>(())
 		}));

-
+		let mut bloom = StateDB::load_bloom(&backing);
 		// batch trie writes
 		{
 			let mut account_trie = if self.state_root != SHA3_NULL_RLP {
@@ -463,11 +464,14 @@ impl StateRebuilder {
 			};

 			for (hash, thin_rlp) in pairs {
+				bloom.set(hash.as_slice());
 				try!(account_trie.insert(&hash, &thin_rlp));
 			}
 		}

+		let bloom_journal = bloom.drain_journal();
 		let batch = backing.transaction();
+		try!(StateDB::commit_bloom(&batch, bloom_journal));
 		try!(self.db.inject(&batch));
 		try!(backing.write(batch).map_err(::util::UtilError::SimpleString));
 		trace!(target: "snapshot", "current state root: {:?}", self.state_root);
--- a/ethcore/src/spec/spec.rs
+++ b/ethcore/src/spec/spec.rs
@@ -20,6 +20,7 @@ use common::*;
 use engines::{Engine, NullEngine, InstantSeal, BasicAuthority};
 use pod_state::*;
 use account_db::*;
+use state_db::StateDB;
 use super::genesis::Genesis;
 use super::seal::Generic as GenericSeal;
 use ethereum;
@@ -229,19 +230,20 @@ impl Spec {
 	}

 	/// Ensure that the given state DB has the trie nodes in for the genesis state.
-	pub fn ensure_db_good(&self, db: &mut HashDB) -> Result<bool, Box<TrieError>> {
-		if !db.contains(&self.state_root()) {
+	pub fn ensure_db_good(&self, db: &mut StateDB) -> Result<bool, Box<TrieError>> {
+		if !db.as_hashdb().contains(&self.state_root()) {
 			let mut root = H256::new();
 			{
-				let mut t = SecTrieDBMut::new(db, &mut root);
+				let mut t = SecTrieDBMut::new(db.as_hashdb_mut(), &mut root);
 				for (address, account) in self.genesis_state.get().iter() {
 					try!(t.insert(address.as_slice(), &account.rlp()));
 				}
 			}
 			for (address, account) in self.genesis_state.get().iter() {
-				account.insert_additional(&mut AccountDBMut::new(db, address));
+				db.note_account_bloom(address);
+				account.insert_additional(&mut AccountDBMut::new(db.as_hashdb_mut(), address));
 			}
-			assert!(db.contains(&self.state_root()));
+			assert!(db.as_hashdb().contains(&self.state_root()));
 			Ok(true)
 		} else { Ok(false) }
 	}
--- a/ethcore/src/state.rs
+++ b/ethcore/src/state.rs
@@ -15,7 +15,7 @@
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.

 use std::cell::{RefCell, RefMut};
-
+use std::collections::hash_map::Entry;
 use common::*;
 use engines::Engine;
 use executive::{Executive, TransactOptions};
@@ -25,6 +25,7 @@ use trace::FlatTrace;
 use pod_account::*;
 use pod_state::{self, PodState};
 use types::state_diff::StateDiff;
+use state_db::StateDB;

 /// Used to return information about an `State::apply` operation.
 pub struct ApplyOutcome {
@@ -37,23 +38,166 @@ pub struct ApplyOutcome {
 /// Result type for the execution ("application") of a transaction.
 pub type ApplyResult = Result<ApplyOutcome, Error>;

+#[derive(Eq, PartialEq, Clone, Copy, Debug)]
+/// Account modification state. Used to check if the account was
+/// Modified in between commits and overall.
+enum AccountState {
+	/// Account was loaded from disk and never modified in this state object.
+	CleanFresh,
+	/// Account was loaded from the global cache and never modified.
+	CleanCached,
+	/// Account has been modified and is not committed to the trie yet.
+	/// This is set if any of the account data is changed, including
+	/// storage and code.
+	Dirty,
+	/// Account was modified and committed to the trie.
+	Committed,
+}
+
+#[derive(Debug)]
+/// In-memory copy of the account data. Holds the optional account
+/// and the modification status.
+/// Account entry can contain existing (`Some`) or non-existing
+/// account (`None`)
+struct AccountEntry {
+	account: Option<Account>,
+	state: AccountState,
+}
+
+// Account cache item. Contains account data and
+// modification state
+impl AccountEntry {
+	fn is_dirty(&self) -> bool {
+		self.state == AccountState::Dirty
+	}
+
+	/// Clone dirty data into new `AccountEntry`. This includes
+	/// basic account data and modified storage keys.
+	/// Returns None if clean.
+	fn clone_if_dirty(&self) -> Option<AccountEntry> {
+		match self.is_dirty() {
+			true => Some(self.clone_dirty()),
+			false => None,
+		}
+	}
+
+	/// Clone dirty data into new `AccountEntry`. This includes
+	/// basic account data and modified storage keys.
+	fn clone_dirty(&self) -> AccountEntry {
+		AccountEntry {
+			account: self.account.as_ref().map(Account::clone_dirty),
+			state: self.state,
+		}
+	}
+
+	// Create a new account entry and mark it as dirty.
+	fn new_dirty(account: Option<Account>) -> AccountEntry {
+		AccountEntry {
+			account: account,
+			state: AccountState::Dirty,
+		}
+	}
+
+	// Create a new account entry and mark it as clean.
+	fn new_clean(account: Option<Account>) -> AccountEntry {
+		AccountEntry {
+			account: account,
+			state: AccountState::CleanFresh,
+		}
+	}
+
+	// Create a new account entry and mark it as clean and cached.
+	fn new_clean_cached(account: Option<Account>) -> AccountEntry {
+		AccountEntry {
+			account: account,
+			state: AccountState::CleanCached,
+		}
+	}
+
+	// Replace data with another entry but preserve storage cache.
+	fn overwrite_with(&mut self, other: AccountEntry) {
+		self.state = other.state;
+		match other.account {
+			Some(acc) => match self.account {
+				Some(ref mut ours) => {
+					ours.overwrite_with(acc);
+				},
+				None => {},
+			},
+			None => self.account = None,
+		}
+	}
+}
+
 /// Representation of the entire state of all accounts in the system.
+///
+/// `State` can work together with `StateDB` to share account cache.
+///
+/// Local cache contains changes made locally and changes accumulated
+/// locally from previous commits. Global cache reflects the database
+/// state and never contains any changes.
+///
+/// Cache items contains account data, or the flag that account does not exist
+/// and modification state (see `AccountState`)
+///
+/// Account data can be in the following cache states:
+/// * In global but not local - something that was queried from the database,
+/// but never modified
+/// * In local but not global - something that was just added (e.g. new account)
+/// * In both with the same value - something that was changed to a new value,
+/// but changed back to a previous block in the same block (same State instance)
+/// * In both with different values - something that was overwritten with a
+/// new value.
+///
+/// All read-only state queries check local cache/modifications first,
+/// then global state cache. If data is not found in any of the caches
+/// it is loaded from the DB to the local cache.
+///
+/// **** IMPORTANT *************************************************************
+/// All the modifications to the account data must set the `Dirty` state in the
+/// `AccountEntry`. This is done in `require` and `require_or_from`. So just
+/// use that.
+/// ****************************************************************************
+///
+/// Upon destruction all the local cache data merged into the global cache.
+/// The merge might be rejected if current state is non-canonical.
+///
+/// State snapshotting.
+///
+/// A new snapshot can be created with `snapshot()`. Snapshots can be
+/// created in a hierarchy.
+/// When a snapshot is active all changes are applied directly into
+/// `cache` and the original value is copied into an active snapshot.
+/// Reverting a snapshot with `revert_to_snapshot` involves copying
+/// original values from the latest snapshot back into `cache`. The code
+/// takes care not to overwrite cached storage while doing that.
+/// Snapshot can be discateded with `discard_snapshot`. All of the orignal
+/// backed-up values are moved into a parent snapshot (if any).
+///
 pub struct State {
-	db: Box<JournalDB>,
+	db: StateDB,
 	root: H256,
-	cache: RefCell<HashMap<Address, Option<Account>>>,
-	snapshots: RefCell<Vec<HashMap<Address, Option<Option<Account>>>>>,
+	cache: RefCell<HashMap<Address, AccountEntry>>,
+	// The original account is preserved in
+	snapshots: RefCell<Vec<HashMap<Address, Option<AccountEntry>>>>,
 	account_start_nonce: U256,
 	trie_factory: TrieFactory,
 }

+#[derive(Copy, Clone)]
+enum RequireCache {
+	None,
+	CodeSize,
+	Code,
+}
+
 const SEC_TRIE_DB_UNWRAP_STR: &'static str = "A state can only be created with valid root. Creating a SecTrieDB with a valid root will not fail. \
 			 Therefore creating a SecTrieDB with this state's root will not fail.";

 impl State {
 	/// Creates new state with empty state root
 	#[cfg(test)]
-	pub fn new(mut db: Box<JournalDB>, account_start_nonce: U256, trie_factory: TrieFactory) -> State {
+	pub fn new(mut db: StateDB, account_start_nonce: U256, trie_factory: TrieFactory) -> State {
 		let mut root = H256::new();
 		{
 			// init trie and reset root too null
@@ -71,7 +215,7 @@ impl State {
 	}

 	/// Creates new state with existing state root
-	pub fn from_existing(db: Box<JournalDB>, root: H256, account_start_nonce: U256, trie_factory: TrieFactory) -> Result<State, TrieError> {
+	pub fn from_existing(db: StateDB, root: H256, account_start_nonce: U256, trie_factory: TrieFactory) -> Result<State, TrieError> {
 		if !db.as_hashdb().contains(&root) {
 			return Err(TrieError::InvalidStateRoot(root));
 		}
@@ -88,45 +232,72 @@ impl State {
 		Ok(state)
 	}

-	/// Create a recoverable snaphot of this state
+	/// Create a recoverable snaphot of this state.
 	pub fn snapshot(&mut self) {
 		self.snapshots.borrow_mut().push(HashMap::new());
 	}

-	/// Merge last snapshot with previous
-	pub fn clear_snapshot(&mut self) {
+	/// Merge last snapshot with previous.
+	pub fn discard_snapshot(&mut self) {
 		// merge with previous snapshot
 		let last = self.snapshots.borrow_mut().pop();
 		if let Some(mut snapshot) = last {
 			if let Some(ref mut prev) = self.snapshots.borrow_mut().last_mut() {
-				for (k, v) in snapshot.drain() {
-					prev.entry(k).or_insert(v);
-				}
-			}
-		}
-	}
-
-	/// Revert to snapshot
-	pub fn revert_snapshot(&mut self) {
-		if let Some(mut snapshot) = self.snapshots.borrow_mut().pop() {
-			for (k, v) in snapshot.drain() {
-				match v {
-					Some(v) => {
-						self.cache.borrow_mut().insert(k, v);
-					},
-					None => {
-						self.cache.borrow_mut().remove(&k);
+				if prev.is_empty() {
+					**prev = snapshot;
+				} else {
+					for (k, v) in snapshot.drain() {
+						prev.entry(k).or_insert(v);
 					}
 				}
 			}
 		}
 	}

-	fn insert_cache(&self, address: &Address, account: Option<Account>) {
-		if let Some(ref mut snapshot) = self.snapshots.borrow_mut().last_mut() {
-			if !snapshot.contains_key(address) {
-				snapshot.insert(address.clone(), self.cache.borrow_mut().insert(address.clone(), account));
-				return;
+	/// Revert to the last snapshot and discard it.
+	pub fn revert_to_snapshot(&mut self) {
+		if let Some(mut snapshot) = self.snapshots.borrow_mut().pop() {
+			for (k, v) in snapshot.drain() {
+				match v {
+					Some(v) => {
+						match self.cache.borrow_mut().entry(k) {
+							Entry::Occupied(mut e) => {
+								// Merge snapshotted changes back into the main account
+								// storage preserving the cache.
+								e.get_mut().overwrite_with(v);
+							},
+							Entry::Vacant(e) => {
+								e.insert(v);
+							}
+						}
+					},
+					None => {
+						match self.cache.borrow_mut().entry(k) {
+							Entry::Occupied(e) => {
+								if e.get().is_dirty() {
+									e.remove();
+								}
+							},
+							_ => {}
+						}
+					}
+				}
+			}
+		}
+	}
+
+	fn insert_cache(&self, address: &Address, account: AccountEntry) {
+		// Dirty account which is not in the cache means this is a new account.
+		// It goes directly into the snapshot as there's nothing to rever to.
+		//
+		// In all other cases account is read as clean first, and after that made
+		// dirty in and added to the snapshot with `note_cache`.
+		if account.is_dirty() {
+			if let Some(ref mut snapshot) = self.snapshots.borrow_mut().last_mut() {
+				if !snapshot.contains_key(address) {
+					snapshot.insert(address.clone(), self.cache.borrow_mut().insert(address.clone(), account));
+					return;
+				}
 			}
 		}
 		self.cache.borrow_mut().insert(address.clone(), account);
@@ -135,13 +306,14 @@ impl State {
 	fn note_cache(&self, address: &Address) {
 		if let Some(ref mut snapshot) = self.snapshots.borrow_mut().last_mut() {
 			if !snapshot.contains_key(address) {
-				snapshot.insert(address.clone(), self.cache.borrow().get(address).cloned());
+				snapshot.insert(address.clone(), self.cache.borrow().get(address).map(AccountEntry::clone_dirty));
 			}
 		}
 	}

 	/// Destroy the current object and return root and database.
-	pub fn drop(self) -> (H256, Box<JournalDB>) {
+	pub fn drop(mut self) -> (H256, StateDB) {
+		self.update_shared_cache();
 		(self.root, self.db)
 	}

@@ -153,53 +325,113 @@ impl State {
 	/// Create a new contract at address `contract`. If there is already an account at the address
 	/// it will have its code reset, ready for `init_code()`.
 	pub fn new_contract(&mut self, contract: &Address, balance: U256) {
-		self.insert_cache(contract, Some(Account::new_contract(balance, self.account_start_nonce)));
+		self.insert_cache(contract, AccountEntry::new_dirty(Some(Account::new_contract(balance, self.account_start_nonce))));
 	}

 	/// Remove an existing account.
 	pub fn kill_account(&mut self, account: &Address) {
-		self.insert_cache(account, None);
+		self.insert_cache(account, AccountEntry::new_dirty(None));
 	}

 	/// Determine whether an account exists.
 	pub fn exists(&self, a: &Address) -> bool {
-		self.ensure_cached(a, false, |a| a.is_some())
+		self.ensure_cached(a, RequireCache::None, |a| a.is_some())
 	}

 	/// Get the balance of account `a`.
 	pub fn balance(&self, a: &Address) -> U256 {
-		self.ensure_cached(a, false,
+		self.ensure_cached(a, RequireCache::None,
 			|a| a.as_ref().map_or(U256::zero(), |account| *account.balance()))
 	}

 	/// Get the nonce of account `a`.
 	pub fn nonce(&self, a: &Address) -> U256 {
-		self.ensure_cached(a, false,
+		self.ensure_cached(a, RequireCache::None,
 			|a| a.as_ref().map_or(self.account_start_nonce, |account| *account.nonce()))
 	}

 	/// Mutate storage of account `address` so that it is `value` for `key`.
 	pub fn storage_at(&self, address: &Address, key: &H256) -> H256 {
-		self.ensure_cached(address, false,
-			|a| a.as_ref().map_or(H256::new(), |a|a.storage_at(&AccountDB::from_hash(self.db.as_hashdb(), a.address_hash(address)), key)))
+		// Storage key search and update works like this:
+		// 1. Check bloom to see if account never used surely
+		// 2. If there's an entry for the account in the local cache check for the key and return it if found.
+		// 3. If there's an entry for the account in the global cache check for the key or load it into that account.
+		// 4. If account is missing in the global cache load it into the local cache and cache the key there.
+
+		// check bloom
+
+		// check local cache first without updating
+		{
+			let local_cache = self.cache.borrow_mut();
+			let mut local_account = None;
+			if let Some(maybe_acc) = local_cache.get(address) {
+				match maybe_acc.account {
+					Some(ref account) => {
+						if let Some(value) = account.cached_storage_at(key) {
+							return value;
+						} else {
+							local_account = Some(maybe_acc);
+						}
+					},
+					_ => return H256::new(),
+				}
+			}
+			// check the global cache and and cache storage key there if found,
+			// otherwise cache the account localy and cache storage key there.
+			if let Some(result) = self.db.get_cached(address, |acc| acc.map_or(H256::new(), |a| a.storage_at(&AccountDB::from_hash(self.db.as_hashdb(), a.address_hash(address)), key))) {
+				return result;
+			}
+			if let Some(ref mut acc) = local_account {
+				if let Some(ref account) = acc.account {
+					return account.storage_at(&AccountDB::from_hash(self.db.as_hashdb(), account.address_hash(address)), key)
+				} else {
+					return H256::new()
+				}
+			}
+		}
+		// account is not found in the global cache, get from the DB and insert into local
+		if !self.db.check_account_bloom(address) { return H256::zero() }
+		let db = self.trie_factory.readonly(self.db.as_hashdb(), &self.root).expect(SEC_TRIE_DB_UNWRAP_STR);
+		let maybe_acc = match db.get(address) {
+			Ok(acc) => acc.map(Account::from_rlp),
+			Err(e) => panic!("Potential DB corruption encountered: {}", e),
+		};
+		let r = maybe_acc.as_ref().map_or(H256::new(), |a| a.storage_at(&AccountDB::from_hash(self.db.as_hashdb(), a.address_hash(address)), key));
+		self.insert_cache(address, AccountEntry::new_clean(maybe_acc));
+		r
 	}

-	/// Mutate storage of account `a` so that it is `value` for `key`.
-	pub fn code(&self, a: &Address) -> Option<Bytes> {
-		self.ensure_cached(a, true,
-			|a| a.as_ref().map_or(None, |a|a.code().map(|x|x.to_vec())))
+	/// Get accounts' code.
+	pub fn code(&self, a: &Address) -> Option<Arc<Bytes>> {
+		self.ensure_cached(a, RequireCache::Code,
+			|a| a.as_ref().map_or(None, |a| a.code().clone()))
+	}
+
+	pub fn code_hash(&self, a: &Address) -> H256 {
+		self.ensure_cached(a, RequireCache::None,
+			|a| a.as_ref().map_or(SHA3_EMPTY, |a| a.code_hash()))
+	}
+
+	/// Get accounts' code size.
+	pub fn code_size(&self, a: &Address) -> Option<u64> {
+		self.ensure_cached(a, RequireCache::CodeSize,
+			|a| a.as_ref().and_then(|a| a.code_size()))
 	}

 	/// Add `incr` to the balance of account `a`.
 	pub fn add_balance(&mut self, a: &Address, incr: &U256) {
 		trace!(target: "state", "add_balance({}, {}): {}", a, incr, self.balance(a));
-		self.require(a, false).add_balance(incr);
+		if !incr.is_zero() || !self.exists(a) {
+			self.require(a, false).add_balance(incr);
+		}
 	}

 	/// Subtract `decr` from the balance of account `a`.
 	pub fn sub_balance(&mut self, a: &Address, decr: &U256) {
 		trace!(target: "state", "sub_balance({}, {}): {}", a, decr, self.balance(a));
-		self.require(a, false).sub_balance(decr);
+		if !decr.is_zero() || !self.exists(a) {
+			self.require(a, false).sub_balance(decr);
+		}
 	}

 	/// Subtracts `by` from the balance of `from` and adds it to that of `to`.
@@ -215,7 +447,9 @@ impl State {

 	/// Mutate storage of account `a` so that it is `value` for `key`.
 	pub fn set_storage(&mut self, a: &Address, key: H256, value: H256) {
-		self.require(a, false).set_storage(key, value)
+		if self.storage_at(a, &key) != value {
+			self.require(a, false).set_storage(key, value)
+		}
 	}

 	/// Initialise the code of account `a` so that it is `code`.
@@ -248,19 +482,18 @@ impl State {
 	/// Commit accounts to SecTrieDBMut. This is similar to cpp-ethereum's dev::eth::commit.
 	/// `accounts` is mutable because we may need to commit the code or storage and record that.
 	#[cfg_attr(feature="dev", allow(match_ref_pats))]
-	pub fn commit_into(
+	fn commit_into(
 		trie_factory: &TrieFactory,
-		db: &mut HashDB,
+		db: &mut StateDB,
 		root: &mut H256,
-		accounts: &mut HashMap<Address,
-		Option<Account>>
+		accounts: &mut HashMap<Address, AccountEntry>
 	) -> Result<(), Error> {
 		// first, commit the sub trees.
-		// TODO: is this necessary or can we dispense with the `ref mut a` for just `a`?
-		for (address, ref mut a) in accounts.iter_mut() {
-			match a {
-				&mut&mut Some(ref mut account) if account.is_dirty() => {
-					let mut account_db = AccountDBMut::from_hash(db, account.address_hash(address));
+		for (address, ref mut a) in accounts.iter_mut().filter(|&(_, ref a)| a.is_dirty()) {
+			match a.account {
+				Some(ref mut account) => {
+					db.note_account_bloom(&address);
+					let mut account_db = AccountDBMut::from_hash(db.as_hashdb_mut(), account.address_hash(address));
 					account.commit_storage(trie_factory, &mut account_db);
 					account.commit_code(&mut account_db);
 				}
@@ -269,15 +502,16 @@ impl State {
 		}

 		{
-			let mut trie = trie_factory.from_existing(db, root).unwrap();
-			for (address, ref mut a) in accounts.iter_mut() {
-				match **a {
-					Some(ref mut account) if account.is_dirty() => {
-						account.set_clean();
-						try!(trie.insert(address, &account.rlp()))
+			let mut trie = trie_factory.from_existing(db.as_hashdb_mut(), root).unwrap();
+			for (address, ref mut a) in accounts.iter_mut().filter(|&(_, ref a)| a.is_dirty()) {
+				a.state = AccountState::Committed;
+				match a.account {
+					Some(ref mut account) => {
+						try!(trie.insert(address, &account.rlp()));
+					},
+					None => {
+						try!(trie.remove(address));
 					},
-					None => try!(trie.remove(address)),
-					_ => (),
 				}
 			}
 		}
@@ -285,10 +519,19 @@ impl State {
 		Ok(())
 	}

+	/// Merge local cache into shared canonical state cache.
+	fn update_shared_cache(&mut self) {
+		let mut addresses = self.cache.borrow_mut();
+		trace!("Committing cache {:?} entries", addresses.len());
+		for (address, a) in addresses.drain().filter(|&(_, ref a)| a.state == AccountState::Committed || a.state == AccountState::CleanFresh) {
+			self.db.add_to_account_cache(address, a.account, a.state == AccountState::Committed);
+		}
+	}
+
 	/// Commits our cached account changes into the trie.
 	pub fn commit(&mut self) -> Result<(), Error> {
 		assert!(self.snapshots.borrow().is_empty());
-		Self::commit_into(&self.trie_factory, self.db.as_hashdb_mut(), &mut self.root, &mut *self.cache.borrow_mut())
+		Self::commit_into(&self.trie_factory, &mut self.db, &mut self.root, &mut *self.cache.borrow_mut())
 	}

 	/// Clear state cache
@@ -302,7 +545,8 @@ impl State {
 	pub fn populate_from(&mut self, accounts: PodState) {
 		assert!(self.snapshots.borrow().is_empty());
 		for (add, acc) in accounts.drain().into_iter() {
-			self.cache.borrow_mut().insert(add, Some(Account::from_pod(acc)));
+			self.db.note_account_bloom(&add);
+			self.cache.borrow_mut().insert(add, AccountEntry::new_dirty(Some(Account::from_pod(acc))));
 		}
 	}

@@ -312,7 +556,7 @@ impl State {
 		// TODO: handle database rather than just the cache.
 		// will need fat db.
 		PodState::from(self.cache.borrow().iter().fold(BTreeMap::new(), |mut m, (add, opt)| {
-			if let Some(ref acc) = *opt {
+			if let Some(ref acc) = opt.account {
 				m.insert(add.clone(), PodAccount::from_account(acc));
 			}
 			m
@@ -321,7 +565,7 @@ impl State {

 	fn query_pod(&mut self, query: &PodState) {
 		for (ref address, ref pod_account) in query.get() {
-			self.ensure_cached(address, true, |a| {
+			self.ensure_cached(address, RequireCache::Code, |a| {
 				if a.is_some() {
 					for key in pod_account.storage.keys() {
 						self.storage_at(address, key);
@@ -340,27 +584,58 @@ impl State {
 		pod_state::diff_pod(&state_pre.to_pod(), &pod_state_post)
 	}

-	/// Ensure account `a` is in our cache of the trie DB and return a handle for getting it.
-	/// `require_code` requires that the code be cached, too.
-	fn ensure_cached<'a, F, U>(&'a self, a: &'a Address, require_code: bool, f: F) -> U
-		where F: FnOnce(&Option<Account>) -> U {
-		let have_key = self.cache.borrow().contains_key(a);
-		if !have_key {
-			let db = self.trie_factory.readonly(self.db.as_hashdb(), &self.root).expect(SEC_TRIE_DB_UNWRAP_STR);
-			let maybe_acc = match db.get(a) {
-				Ok(acc) => acc.map(Account::from_rlp),
-				Err(e) => panic!("Potential DB corruption encountered: {}", e),
-			};
-			self.insert_cache(a, maybe_acc);
-		}
-		if require_code {
-			if let Some(ref mut account) = self.cache.borrow_mut().get_mut(a).unwrap().as_mut() {
-				let addr_hash = account.address_hash(a);
-				account.cache_code(&AccountDB::from_hash(self.db.as_hashdb(), addr_hash));
+	fn update_account_cache(require: RequireCache, account: &mut Account, address: &Address, db: &HashDB) {
+		match require {
+			RequireCache::None => {},
+			RequireCache::Code => {
+				let address_hash = account.address_hash(address);
+				account.cache_code(&AccountDB::from_hash(db, address_hash));
+			}
+			RequireCache::CodeSize => {
+				let address_hash = account.address_hash(address);
+				account.cache_code_size(&AccountDB::from_hash(db, address_hash));
 			}
 		}
+	}

-		f(self.cache.borrow().get(a).unwrap())
+	/// Check caches for required data
+	/// First searches for account in the local, then the shared cache.
+	/// Populates local cache if nothing found.
+	fn ensure_cached<F, U>(&self, a: &Address, require: RequireCache, f: F) -> U
+		where F: Fn(Option<&Account>) -> U {
+		// check local cache first
+		if let Some(ref mut maybe_acc) = self.cache.borrow_mut().get_mut(a) {
+			if let Some(ref mut account) = maybe_acc.account {
+				Self::update_account_cache(require, account, a, self.db.as_hashdb());
+				return f(Some(account));
+			}
+			return f(None);
+		}
+		// check global cache
+		let result = self.db.get_cached(a, |mut acc| {
+			if let Some(ref mut account) = acc {
+				Self::update_account_cache(require, account, a, self.db.as_hashdb());
+			}
+			f(acc.map(|a| &*a))
+		});
+		match result {
+			Some(r) => r,
+			None => {
+				// not found in the global cache, get from the DB and insert into local
+				if !self.db.check_account_bloom(a) { return f(None); }
+				let db = self.trie_factory.readonly(self.db.as_hashdb(), &self.root).expect(SEC_TRIE_DB_UNWRAP_STR);
+				let mut maybe_acc = match db.get(a) {
+					Ok(acc) => acc.map(Account::from_rlp),
+					Err(e) => panic!("Potential DB corruption encountered: {}", e),
+				};
+				if let Some(ref mut account) = maybe_acc.as_mut() {
+					Self::update_account_cache(require, account, a, self.db.as_hashdb());
+				}
+				let r = f(maybe_acc.as_ref());
+				self.insert_cache(a, AccountEntry::new_clean(maybe_acc));
+				r
+			}
+		}
 	}

 	/// Pull account `a` in our cache from the trie DB. `require_code` requires that the code be cached, too.
@@ -375,29 +650,47 @@ impl State {
 	{
 		let contains_key = self.cache.borrow().contains_key(a);
 		if !contains_key {
-			let db = self.trie_factory.readonly(self.db.as_hashdb(), &self.root).expect(SEC_TRIE_DB_UNWRAP_STR);
-			let maybe_acc = match db.get(a) {
-				Ok(acc) => acc.map(Account::from_rlp),
-				Err(e) => panic!("Potential DB corruption encountered: {}", e),
-			};
-
-			self.insert_cache(a, maybe_acc);
-		} else {
-			self.note_cache(a);
-		}
-
-		match self.cache.borrow_mut().get_mut(a).unwrap() {
-			&mut Some(ref mut acc) => not_default(acc),
-			slot @ &mut None => *slot = Some(default()),
-		}
-
-		RefMut::map(self.cache.borrow_mut(), |c| {
-			let account = c.get_mut(a).unwrap().as_mut().unwrap();
-			if require_code {
-				let addr_hash = account.address_hash(a);
-				account.cache_code(&AccountDB::from_hash(self.db.as_hashdb(), addr_hash));
+			match self.db.get_cached_account(a) {
+				Some(acc) => self.insert_cache(a, AccountEntry::new_clean_cached(acc)),
+				None => {
+					let maybe_acc = if self.db.check_account_bloom(a) {
+						let db = self.trie_factory.readonly(self.db.as_hashdb(), &self.root).expect(SEC_TRIE_DB_UNWRAP_STR);
+						let maybe_acc = match db.get(a) {
+							Ok(Some(acc)) => AccountEntry::new_clean(Some(Account::from_rlp(acc))),
+							Ok(None) => AccountEntry::new_clean(None),
+							Err(e) => panic!("Potential DB corruption encountered: {}", e),
+						};
+						maybe_acc
+					}
+					else {
+						AccountEntry::new_clean(None)
+					};
+					self.insert_cache(a, maybe_acc);
+				}
+			}
+		}
+		self.note_cache(a);
+
+		match &mut self.cache.borrow_mut().get_mut(a).unwrap().account {
+			&mut Some(ref mut acc) => not_default(acc),
+			slot => *slot = Some(default()),
+		}
+
+		// at this point the account is guaranteed to be in the cache.
+		RefMut::map(self.cache.borrow_mut(), |c| {
+			let mut entry = c.get_mut(a).unwrap();
+			// set the dirty flag after changing account data.
+			entry.state = AccountState::Dirty;
+			match entry.account {
+				Some(ref mut account) => {
+					if require_code {
+						let addr_hash = account.address_hash(a);
+						account.cache_code(&AccountDB::from_hash(self.db.as_hashdb(), addr_hash));
+					}
+					account
+				},
+				_ => panic!("Required account must always exist; qed"),
 			}
-			account
 		})
 	}
 }
@@ -410,11 +703,21 @@ impl fmt::Debug for State {

 impl Clone for State {
 	fn clone(&self) -> State {
+		let cache = {
+			let mut cache: HashMap<Address, AccountEntry> = HashMap::new();
+			for (key, val) in self.cache.borrow().iter() {
+				if let Some(entry) = val.clone_if_dirty() {
+					cache.insert(key.clone(), entry);
+				}
+			}
+			cache
+		};
+
 		State {
 			db: self.db.boxed_clone(),
 			root: self.root.clone(),
-			cache: RefCell::new(self.cache.borrow().clone()),
-			snapshots: RefCell::new(self.snapshots.borrow().clone()),
+			cache: RefCell::new(cache),
+			snapshots: RefCell::new(Vec::new()),
 			account_start_nonce: self.account_start_nonce.clone(),
 			trie_factory: self.trie_factory.clone(),
 		}
@@ -1304,14 +1607,14 @@ fn code_from_database() {
 		let mut state = get_temp_state_in(temp.as_path());
 		state.require_or_from(&a, false, ||Account::new_contract(42.into(), 0.into()), |_|{});
 		state.init_code(&a, vec![1, 2, 3]);
-		assert_eq!(state.code(&a), Some([1u8, 2, 3].to_vec()));
+		assert_eq!(state.code(&a), Some(Arc::new([1u8, 2, 3].to_vec())));
 		state.commit().unwrap();
-		assert_eq!(state.code(&a), Some([1u8, 2, 3].to_vec()));
+		assert_eq!(state.code(&a), Some(Arc::new([1u8, 2, 3].to_vec())));
 		state.drop()
 	};

 	let state = State::from_existing(db, root, U256::from(0u8), Default::default()).unwrap();
-	assert_eq!(state.code(&a), Some([1u8, 2, 3].to_vec()));
+	assert_eq!(state.code(&a), Some(Arc::new([1u8, 2, 3].to_vec())));
 }

 #[test]
@@ -1459,12 +1762,12 @@ fn snapshot_basic() {
 	state.snapshot();
 	state.add_balance(&a, &U256::from(69u64));
 	assert_eq!(state.balance(&a), U256::from(69u64));
-	state.clear_snapshot();
+	state.discard_snapshot();
 	assert_eq!(state.balance(&a), U256::from(69u64));
 	state.snapshot();
 	state.add_balance(&a, &U256::from(1u64));
 	assert_eq!(state.balance(&a), U256::from(70u64));
-	state.revert_snapshot();
+	state.revert_to_snapshot();
 	assert_eq!(state.balance(&a), U256::from(69u64));
 }

@@ -1477,9 +1780,9 @@ fn snapshot_nested() {
 	state.snapshot();
 	state.add_balance(&a, &U256::from(69u64));
 	assert_eq!(state.balance(&a), U256::from(69u64));
-	state.clear_snapshot();
+	state.discard_snapshot();
 	assert_eq!(state.balance(&a), U256::from(69u64));
-	state.revert_snapshot();
+	state.revert_to_snapshot();
 	assert_eq!(state.balance(&a), U256::from(0));
 }

--- a/ethcore/src/state_db.rs
+++ b/ethcore/src/state_db.rs
@@ -0,0 +1,469 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+use std::collections::{VecDeque, HashSet};
+use lru_cache::LruCache;
+use util::journaldb::JournalDB;
+use util::hash::{H256};
+use util::hashdb::HashDB;
+use account::Account;
+use header::BlockNumber;
+use util::{Arc, Address, Database, DBTransaction, UtilError, Mutex, Hashable, BytesConvertable};
+use bloomfilter::{Bloom, BloomJournal};
+use client::DB_COL_ACCOUNT_BLOOM;
+use byteorder::{LittleEndian, ByteOrder};
+
+const STATE_CACHE_ITEMS: usize = 256000;
+const STATE_CACHE_BLOCKS: usize = 8;
+
+/// Shared canonical state cache.
+struct AccountCache {
+	/// DB Account cache. `None` indicates that account is known to be missing.
+	accounts: LruCache<Address, Option<Account>>,
+	/// Accounts changed in recently committed blocks. Ordered by block number.
+	modifications: VecDeque<BlockChanges>,
+}
+
+/// Buffered account cache item.
+struct CacheQueueItem {
+	/// Account address.
+	address: Address,
+	/// Acccount data or `None` if account does not exist.
+	account: Option<Account>,
+	/// Indicates that the account was modified before being
+	/// added to the cache.
+	modified: bool,
+}
+
+#[derive(Debug)]
+/// Accumulates a list of accounts changed in a block.
+struct BlockChanges {
+	/// Block number.
+	number: BlockNumber,
+	/// Block hash.
+	hash: H256,
+	/// Parent block hash.
+	parent: H256,
+	/// A set of modified account addresses.
+	accounts: HashSet<Address>,
+	/// Block is part of the canonical chain.
+	is_canon: bool,
+}
+
+/// State database abstraction.
+/// Manages shared global state cache.
+/// A clone of `StateDB` may be created as canonical or not.
+/// For canonical clones cache changes are accumulated and applied
+/// on commit.
+/// For non-canonical clones cache is cleared on commit.
+pub struct StateDB {
+	/// Backing database.
+	db: Box<JournalDB>,
+	/// Shared canonical state cache.
+	account_cache: Arc<Mutex<AccountCache>>,
+	/// Local cache buffer.
+	cache_buffer: Vec<CacheQueueItem>,
+	/// Shared account bloom. Does not handle chain reorganizations.
+	account_bloom: Arc<Mutex<Bloom>>,
+	/// Hash of the block on top of which this instance was created or
+	/// `None` if cache is disabled
+	parent_hash: Option<H256>,
+	/// Hash of the committing block or `None` if not committed yet.
+	commit_hash: Option<H256>,
+	/// Number of the committing block or `None` if not committed yet.
+	commit_number: Option<BlockNumber>,
+}
+
+pub const ACCOUNT_BLOOM_SPACE: usize = 1048576;
+pub const DEFAULT_ACCOUNT_PRESET: usize = 1000000;
+
+pub const ACCOUNT_BLOOM_HASHCOUNT_KEY: &'static [u8] = b"account_hash_count";
+
+impl StateDB {
+	/// Loads accounts bloom from the database
+	/// This bloom is used to handle request for the non-existant account fast
+	pub fn load_bloom(db: &Database) -> Bloom {
+		let hash_count_entry = db.get(DB_COL_ACCOUNT_BLOOM, ACCOUNT_BLOOM_HASHCOUNT_KEY)
+			.expect("Low-level database error");
+
+		if hash_count_entry.is_none() {
+			return Bloom::new(ACCOUNT_BLOOM_SPACE, DEFAULT_ACCOUNT_PRESET);
+		}
+		let hash_count_bytes = hash_count_entry.unwrap();
+		assert_eq!(hash_count_bytes.len(), 1);
+		let hash_count = hash_count_bytes[0];
+
+		let mut bloom_parts = vec![0u64; ACCOUNT_BLOOM_SPACE / 8];
+		let mut key = [0u8; 8];
+		for i in 0..ACCOUNT_BLOOM_SPACE / 8 {
+			LittleEndian::write_u64(&mut key, i as u64);
+			bloom_parts[i] = db.get(DB_COL_ACCOUNT_BLOOM, &key).expect("low-level database error")
+				.and_then(|val| Some(LittleEndian::read_u64(&val[..])))
+				.unwrap_or(0u64);
+		}
+
+		let bloom = Bloom::from_parts(&bloom_parts, hash_count as u32);
+		trace!(target: "account_bloom", "Bloom is {:?} full, hash functions count = {:?}", bloom.how_full(), hash_count);
+		bloom
+	}
+
+	/// Create a new instance wrapping `JournalDB`
+	pub fn new(db: Box<JournalDB>) -> StateDB {
+		let bloom = Self::load_bloom(db.backing());
+		StateDB {
+			db: db,
+			account_cache: Arc::new(Mutex::new(AccountCache {
+				accounts: LruCache::new(STATE_CACHE_ITEMS),
+				modifications: VecDeque::new(),
+			})),
+			cache_buffer: Vec::new(),
+			account_bloom: Arc::new(Mutex::new(bloom)),
+			parent_hash: None,
+			commit_hash: None,
+			commit_number: None,
+		}
+	}
+
+	pub fn check_account_bloom(&self, address: &Address) -> bool {
+		trace!(target: "account_bloom", "Check account bloom: {:?}", address);
+		let bloom = self.account_bloom.lock();
+		bloom.check(address.sha3().as_slice())
+	}
+
+	pub fn note_account_bloom(&self, address: &Address) {
+		trace!(target: "account_bloom", "Note account bloom: {:?}", address);
+		let mut bloom = self.account_bloom.lock();
+		bloom.set(address.sha3().as_slice());
+	}
+
+	pub fn commit_bloom(batch: &DBTransaction, journal: BloomJournal) -> Result<(), UtilError> {
+		assert!(journal.hash_functions <= 255);
+		try!(batch.put(DB_COL_ACCOUNT_BLOOM, ACCOUNT_BLOOM_HASHCOUNT_KEY, &vec![journal.hash_functions as u8]));
+		let mut key = [0u8; 8];
+		let mut val = [0u8; 8];
+
+		for (bloom_part_index, bloom_part_value) in journal.entries {
+			LittleEndian::write_u64(&mut key, bloom_part_index as u64);
+			LittleEndian::write_u64(&mut val, bloom_part_value);
+			try!(batch.put(DB_COL_ACCOUNT_BLOOM, &key, &val));
+		}
+		Ok(())
+	}
+
+	/// Commit all recent insert operations and canonical historical commits' removals from the
+	/// old era to the backing database, reverting any non-canonical historical commit's inserts.
+	pub fn commit(&mut self, batch: &DBTransaction, now: u64, id: &H256, end: Option<(u64, H256)>) -> Result<u32, UtilError> {
+		{
+			let mut bloom_lock = self.account_bloom.lock();
+			try!(Self::commit_bloom(batch, bloom_lock.drain_journal()));
+		}
+
+		let records = try!(self.db.commit(batch, now, id, end));
+		self.commit_hash = Some(id.clone());
+		self.commit_number = Some(now);
+		Ok(records)
+	}
+
+	/// Apply buffered cache changes and synchronize canonical
+	/// state cache with the best block state.
+	/// This function updates the cache by removing entries that are
+	/// invalidated by chain reorganization. `update_cache` should be
+	/// called after the block has been commited and the blockchain
+	/// route has ben calculated.
+	pub fn sync_cache(&mut self, enacted: &[H256], retracted: &[H256], is_best: bool) {
+		trace!("sync_cache id = (#{:?}, {:?}), parent={:?}, best={}", self.commit_number, self.commit_hash, self.parent_hash, is_best);
+		let mut cache = self.account_cache.lock();
+		let mut cache = &mut *cache;
+
+		// Clean changes from re-enacted and retracted blocks
+		let mut clear = false;
+		for block in enacted.iter().filter(|h| self.commit_hash.as_ref().map_or(true, |p| *h != p)) {
+			clear = clear || {
+				if let Some(ref mut m) = cache.modifications.iter_mut().find(|ref m| &m.hash == block) {
+					trace!("Reverting enacted block {:?}", block);
+					m.is_canon = true;
+					for a in &m.accounts {
+						trace!("Reverting enacted address {:?}", a);
+						cache.accounts.remove(a);
+					}
+					false
+				} else {
+					true
+				}
+			};
+		}
+
+		for block in retracted {
+			clear = clear || {
+				if let Some(ref mut m) = cache.modifications.iter_mut().find(|ref m| &m.hash == block) {
+					trace!("Retracting block {:?}", block);
+					m.is_canon = false;
+					for a in &m.accounts {
+						trace!("Retracted address {:?}", a);
+						cache.accounts.remove(a);
+					}
+					false
+				} else {
+					true
+				}
+			};
+		}
+		if clear {
+			// We don't know anything about the block; clear everything
+			trace!("Wiping cache");
+			cache.accounts.clear();
+			cache.modifications.clear();
+		}
+
+		// Apply cache changes only if committing on top of the latest canonical state
+		// blocks are ordered by number and only one block with a given number is marked as canonical
+		// (contributed to canonical state cache)
+		if let (Some(ref number), Some(ref hash), Some(ref parent)) = (self.commit_number, self.commit_hash, self.parent_hash) {
+			if cache.modifications.len() == STATE_CACHE_BLOCKS {
+				cache.modifications.pop_back();
+			}
+			let mut modifications = HashSet::new();
+			trace!("committing {} cache entries", self.cache_buffer.len());
+			for account in self.cache_buffer.drain(..) {
+				if account.modified {
+					modifications.insert(account.address.clone());
+				}
+				if is_best {
+					if let Some(&mut Some(ref mut existing)) = cache.accounts.get_mut(&account.address) {
+						if let Some(new) = account.account {
+							if account.modified {
+								existing.overwrite_with(new);
+							}
+							continue;
+						}
+					}
+					cache.accounts.insert(account.address, account.account);
+				}
+			}
+
+			// Save modified accounts. These are ordered by the block number.
+			let block_changes = BlockChanges {
+				accounts: modifications,
+				number: *number,
+				hash: hash.clone(),
+				is_canon: is_best,
+				parent: parent.clone(),
+			};
+			let insert_at = cache.modifications.iter().enumerate().find(|&(_, ref m)| m.number < *number).map(|(i, _)| i);
+			trace!("inserting modifications at {:?}", insert_at);
+			if let Some(insert_at) = insert_at {
+				cache.modifications.insert(insert_at, block_changes);
+			} else {
+				cache.modifications.push_back(block_changes);
+			}
+		}
+	}
+
+	/// Returns an interface to HashDB.
+	pub fn as_hashdb(&self) -> &HashDB {
+		self.db.as_hashdb()
+	}
+
+	/// Returns an interface to mutable HashDB.
+	pub fn as_hashdb_mut(&mut self) -> &mut HashDB {
+		self.db.as_hashdb_mut()
+	}
+
+	/// Clone the database.
+	pub fn boxed_clone(&self) -> StateDB {
+		StateDB {
+			db: self.db.boxed_clone(),
+			account_cache: self.account_cache.clone(),
+			cache_buffer: Vec::new(),
+			account_bloom: self.account_bloom.clone(),
+			parent_hash: None,
+			commit_hash: None,
+			commit_number: None,
+		}
+	}
+
+	/// Clone the database for a canonical state.
+	pub fn boxed_clone_canon(&self, parent: &H256) -> StateDB {
+		StateDB {
+			db: self.db.boxed_clone(),
+			account_cache: self.account_cache.clone(),
+			cache_buffer: Vec::new(),
+			account_bloom: self.account_bloom.clone(),
+			parent_hash: Some(parent.clone()),
+			commit_hash: None,
+			commit_number: None,
+		}
+	}
+
+	/// Check if pruning is enabled on the database.
+	pub fn is_pruned(&self) -> bool {
+		self.db.is_pruned()
+	}
+
+	/// Heap size used.
+	pub fn mem_used(&self) -> usize {
+		self.db.mem_used() //TODO: + self.account_cache.lock().heap_size_of_children()
+	}
+
+	/// Returns underlying `JournalDB`.
+	pub fn journal_db(&self) -> &JournalDB {
+		&*self.db
+	}
+
+	/// Add pending cache change.
+	/// The change is queued to be applied in `commit`.
+	pub fn add_to_account_cache(&mut self, addr: Address, data: Option<Account>, modified: bool) {
+		self.cache_buffer.push(CacheQueueItem {
+			address: addr,
+			account: data,
+			modified: modified,
+		})
+	}
+
+	/// Get basic copy of the cached account. Does not include storage.
+	/// Returns 'None' if cache is disabled or if the account is not cached.
+	pub fn get_cached_account(&self, addr: &Address) -> Option<Option<Account>> {
+		let mut cache = self.account_cache.lock();
+		if !Self::is_allowed(addr, &self.parent_hash, &cache.modifications) {
+			return None;
+		}
+		cache.accounts.get_mut(&addr).map(|a| a.as_ref().map(|a| a.clone_basic()))
+	}
+
+	/// Get value from a cached account.
+	/// Returns 'None' if cache is disabled or if the account is not cached.
+	pub fn get_cached<F, U>(&self, a: &Address, f: F) -> Option<U>
+		where F: FnOnce(Option<&mut Account>) -> U {
+		let mut cache = self.account_cache.lock();
+		if !Self::is_allowed(a, &self.parent_hash, &cache.modifications) {
+			return None;
+		}
+		cache.accounts.get_mut(a).map(|c| f(c.as_mut()))
+	}
+
+	/// Check if the account can be returned from cache by matching current block parent hash against canonical
+	/// state and filtering out account modified in later blocks.
+	fn is_allowed(addr: &Address, parent_hash: &Option<H256>, modifications: &VecDeque<BlockChanges>) -> bool {
+		let mut parent = match *parent_hash {
+			None => {
+				trace!("Cache lookup skipped for {:?}: no parent hash", addr);
+				return false;
+			}
+			Some(ref parent) => parent,
+		};
+		if modifications.is_empty() {
+			return true;
+		}
+		// Ignore all accounts modified in later blocks
+		// Modifications contains block ordered by the number
+		// We search for our parent in that list first and then for
+		// all its parent until we hit the canonical block,
+		// checking against all the intermediate modifications.
+		let mut iter = modifications.iter();
+		while let Some(ref m) = iter.next() {
+			if &m.hash == parent {
+				if m.is_canon {
+					return true;
+				}
+				parent = &m.parent;
+			}
+			if m.accounts.contains(addr) {
+				trace!("Cache lookup skipped for {:?}: modified in a later block", addr);
+				return false;
+			}
+		}
+		trace!("Cache lookup skipped for {:?}: parent hash is unknown", addr);
+		return false;
+	}
+}
+
+#[cfg(test)]
+mod tests {
+
+use util::{U256, H256, FixedHash, Address, DBTransaction};
+use tests::helpers::*;
+use account::Account;
+use util::log::init_log;
+
+#[test]
+fn state_db_smoke() {
+	init_log();
+
+	let mut state_db_result = get_temp_state_db();
+	let state_db = state_db_result.take();
+	let root_parent = H256::random();
+	let address = Address::random();
+	let h0 = H256::random();
+	let h1a = H256::random();
+	let h1b = H256::random();
+	let h2a = H256::random();
+	let h2b = H256::random();
+	let h3a = H256::random();
+	let h3b = H256::random();
+	let mut batch = DBTransaction::new(state_db.journal_db().backing());
+
+	// blocks  [ 3a(c) 2a(c) 2b 1b 1a(c) 0 ]
+    // balance [ 5     5     4  3  2     2 ]
+	let mut s = state_db.boxed_clone_canon(&root_parent);
+	s.add_to_account_cache(address, Some(Account::new_basic(2.into(), 0.into())), false);
+	s.commit(&mut batch, 0, &h0, None).unwrap();
+	s.sync_cache(&[], &[], true);
+
+	let mut s = state_db.boxed_clone_canon(&h0);
+	s.commit(&mut batch, 1, &h1a, None).unwrap();
+	s.sync_cache(&[], &[], true);
+
+	let mut s = state_db.boxed_clone_canon(&h0);
+	s.add_to_account_cache(address, Some(Account::new_basic(3.into(), 0.into())), true);
+	s.commit(&mut batch, 1, &h1b, None).unwrap();
+	s.sync_cache(&[], &[], false);
+
+	let mut s = state_db.boxed_clone_canon(&h1b);
+	s.add_to_account_cache(address, Some(Account::new_basic(4.into(), 0.into())), true);
+	s.commit(&mut batch, 2, &h2b, None).unwrap();
+	s.sync_cache(&[], &[], false);
+
+	let mut s = state_db.boxed_clone_canon(&h1a);
+	s.add_to_account_cache(address, Some(Account::new_basic(5.into(), 0.into())), true);
+	s.commit(&mut batch, 2, &h2a, None).unwrap();
+	s.sync_cache(&[], &[], true);
+
+	let mut s = state_db.boxed_clone_canon(&h2a);
+	s.commit(&mut batch, 3, &h3a, None).unwrap();
+	s.sync_cache(&[], &[], true);
+
+	let s = state_db.boxed_clone_canon(&h3a);
+	assert_eq!(s.get_cached_account(&address).unwrap().unwrap().balance(), &U256::from(5));
+
+	let s = state_db.boxed_clone_canon(&h1a);
+	assert!(s.get_cached_account(&address).is_none());
+
+	let s = state_db.boxed_clone_canon(&h2b);
+	assert!(s.get_cached_account(&address).is_none());
+
+	let s = state_db.boxed_clone_canon(&h1b);
+	assert!(s.get_cached_account(&address).is_none());
+
+	// reorg to 3b
+	// blocks  [ 3b(c) 3a 2a 2b(c) 1b 1a 0 ]
+	let mut s = state_db.boxed_clone_canon(&h2b);
+	s.commit(&mut batch, 3, &h3b, None).unwrap();
+	s.sync_cache(&[h1b.clone(), h2b.clone(), h3b.clone()], &[h1a.clone(), h2a.clone(), h3a.clone()], true);
+	let s = state_db.boxed_clone_canon(&h3a);
+	assert!(s.get_cached_account(&address).is_none());
+}
+}
+
--- a/ethcore/src/tests/helpers.rs
+++ b/ethcore/src/tests/helpers.rs
@@ -18,6 +18,7 @@ use io::*;
 use client::{self, BlockChainClient, Client, ClientConfig};
 use common::*;
 use spec::*;
+use state_db::StateDB;
 use block::{OpenBlock, Drain};
 use blockchain::{BlockChain, Config as BlockChainConfig};
 use state::*;
@@ -136,9 +137,9 @@ pub fn generate_dummy_client_with_spec_and_data<F>(get_test_spec: F, block_numbe
 	let client = Client::new(ClientConfig::default(), &test_spec, dir.as_path(), Arc::new(Miner::with_spec(&test_spec)), IoChannel::disconnected()).unwrap();
 	let test_engine = &*test_spec.engine;

-	let mut db_result = get_temp_journal_db();
+	let mut db_result = get_temp_state_db();
 	let mut db = db_result.take();
-	test_spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
+	test_spec.ensure_db_good(&mut db).unwrap();
 	let vm_factory = Default::default();
 	let genesis_header = test_spec.genesis_header();

@@ -303,9 +304,9 @@ pub fn generate_dummy_empty_blockchain() -> GuardedTempResult<BlockChain> {
 	}
 }

-pub fn get_temp_journal_db() -> GuardedTempResult<Box<JournalDB>> {
+pub fn get_temp_state_db() -> GuardedTempResult<StateDB> {
 	let temp = RandomTempPath::new();
-	let journal_db = get_temp_journal_db_in(temp.as_path());
+	let journal_db = get_temp_state_db_in(temp.as_path());

 	GuardedTempResult {
 		_temp: temp,
@@ -315,7 +316,7 @@ pub fn get_temp_journal_db() -> GuardedTempResult<Box<JournalDB>> {

 pub fn get_temp_state() -> GuardedTempResult<State> {
 	let temp = RandomTempPath::new();
-	let journal_db = get_temp_journal_db_in(temp.as_path());
+	let journal_db = get_temp_state_db_in(temp.as_path());

 	GuardedTempResult {
 	    _temp: temp,
@@ -323,13 +324,14 @@ pub fn get_temp_state() -> GuardedTempResult<State> {
 	}
 }

-pub fn get_temp_journal_db_in(path: &Path) -> Box<JournalDB> {
+pub fn get_temp_state_db_in(path: &Path) -> StateDB {
 	let db = new_db(path.to_str().expect("Only valid utf8 paths for tests."));
-	journaldb::new(db.clone(), journaldb::Algorithm::EarlyMerge, None)
+	let journal_db = journaldb::new(db.clone(), journaldb::Algorithm::EarlyMerge, client::DB_COL_STATE);
+	StateDB::new(journal_db)
 }

 pub fn get_temp_state_in(path: &Path) -> State {
-	let journal_db = get_temp_journal_db_in(path);
+	let journal_db = get_temp_state_db_in(path);
 	State::new(journal_db, U256::from(0), Default::default())
 }

--- a/ethcore/src/trace/db.rs
+++ b/ethcore/src/trace/db.rs
@@ -268,16 +268,6 @@ impl<T> TraceDatabase for TraceDB<T> where T: DatabaseExtras {
 			return;
 		}

-		// at first, let's insert new block traces
-		{
-			let mut traces = self.traces.write();
-			// it's important to use overwrite here,
-			// cause this value might be queried by hash later
-			batch.write_with_cache(DB_COL_TRACE, &mut *traces, request.block_hash, request.traces, CacheUpdatePolicy::Overwrite);
-			// note_used must be called after locking traces to avoid cache/traces deadlock on garbage collection
-			self.note_used(CacheID::Trace(request.block_hash.clone()));
-		}
-
 		// now let's rebuild the blooms
 		{
 			let range_start = request.block_number as Number + 1 - request.enacted.len();
@@ -288,12 +278,25 @@ impl<T> TraceDatabase for TraceDB<T> where T: DatabaseExtras {
 				// all traces are expected to be found here. That's why `expect` has been used
 				// instead of `filter_map`. If some traces haven't been found, it meens that
 				// traces database is corrupted or incomplete.
-				.map(|block_hash| self.traces(block_hash).expect("Traces database is incomplete."))
-				.map(|block_traces| block_traces.bloom())
+				.map(|block_hash| if block_hash == &request.block_hash {
+					request.traces.bloom()
+				} else {
+					self.traces(block_hash).expect("Traces database is incomplete.").bloom()
+				})
 				.map(blooms::Bloom::from)
 				.map(Into::into)
 				.collect();

+			// insert new block traces into the cache and the database
+			{
+				let mut traces = self.traces.write();
+				// it's important to use overwrite here,
+				// cause this value might be queried by hash later
+				batch.write_with_cache(DB_COL_TRACE, &mut *traces, request.block_hash, request.traces, CacheUpdatePolicy::Overwrite);
+				// note_used must be called after locking traces to avoid cache/traces deadlock on garbage collection
+				self.note_used(CacheID::Trace(request.block_hash.clone()));
+			}
+
 			let chain = BloomGroupChain::new(self.bloom_config, self);
 			let trace_blooms = chain.replace(&replaced_range, enacted_blooms);
 			let blooms_to_insert = trace_blooms.into_iter()
--- a/ethcore/src/types/filter.rs
+++ b/ethcore/src/types/filter.rs
@@ -25,7 +25,7 @@ use std::mem;
 use std::collections::VecDeque;

 /// Blockchain Filter.
-#[derive(Binary)]
+#[derive(Binary, Debug, PartialEq)]
 pub struct Filter {
 	/// Blockchain will be searched from this block.
 	pub from_block: BlockID,
--- a/ethcore/src/types/trace_types/trace.rs
+++ b/ethcore/src/types/trace_types/trace.rs
@@ -181,7 +181,7 @@ impl From<ActionParams> for Create {
 			from: p.sender,
 			value: p.value.value(),
 			gas: p.gas,
-			init: p.code.unwrap_or_else(Vec::new),
+			init: p.code.map_or_else(Vec::new, |c| (*c).clone()),
 		}
 	}
 }
--- a/ethkey/src/primitive.rs
+++ b/ethkey/src/primitive.rs
@@ -24,7 +24,6 @@ macro_rules! impl_primitive {
 	($name: ident, $size: expr, $err: expr) => {

 		#[repr(C)]
-		#[derive(Eq)]
 		pub struct $name([u8; $size]);

 		impl fmt::Debug for $name {
@@ -62,6 +61,8 @@ macro_rules! impl_primitive {
 			}
 		}

+		impl Eq for $name { }
+
 		impl PartialOrd for $name {
 			fn partial_cmp(&self, other: &Self) -> Option<cmp::Ordering> {
 				let self_ref: &[u8] = &self.0;
--- a/ethkey/src/signature.rs
+++ b/ethkey/src/signature.rs
@@ -23,7 +23,6 @@ use rustc_serialize::hex::{ToHex, FromHex};
 use {Secret, Public, SECP256K1, Error, Message, public_to_address, Address};

 #[repr(C)]
-#[derive(Eq)]
 pub struct Signature([u8; 65]);

 impl Signature {
@@ -51,6 +50,9 @@ impl ::std::cmp::PartialEq for Signature {
 	}
 }

+// manual implementation required in Rust 1.13+, see `std::cmp::AssertParamIsEq`.
+impl Eq for Signature { }
+
 // also manual for the same reason, but the pretty printing might be useful.
 impl fmt::Debug for Signature {
 	fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
--- a/ethstore/src/account/safe_account.rs
+++ b/ethstore/src/account/safe_account.rs
@@ -23,7 +23,7 @@ use account::{Version, Cipher, Kdf, Aes128Ctr, Pbkdf2, Prf};
 #[derive(Debug, PartialEq, Clone)]
 pub struct Crypto {
 	pub cipher: Cipher,
-	pub ciphertext: [u8; 32],
+	pub ciphertext: Vec<u8>,
 	pub kdf: Kdf,
 	pub mac: [u8; 32],
 }
@@ -95,7 +95,7 @@ impl Crypto {
 			cipher: Cipher::Aes128Ctr(Aes128Ctr {
 				iv: iv,
 			}),
-			ciphertext: ciphertext,
+			ciphertext: ciphertext.to_vec(),
 			kdf: Kdf::Pbkdf2(Pbkdf2 {
 				dklen: crypto::KEY_LENGTH as u32,
 				salt: salt,
@@ -107,6 +107,10 @@ impl Crypto {
 	}

 	pub fn secret(&self, password: &str) -> Result<Secret, Error> {
+		if self.ciphertext.len() > 32 {
+			return Err(Error::InvalidSecret);
+		}
+
 		let (derived_left_bits, derived_right_bits) = match self.kdf {
 			Kdf::Pbkdf2(ref params) => crypto::derive_key_iterations(password, &params.salt, params.c),
 			Kdf::Scrypt(ref params) => crypto::derive_key_scrypt(password, &params.salt, params.n, params.p, params.r),
@@ -122,7 +126,8 @@ impl Crypto {

 		match self.cipher {
 			Cipher::Aes128Ctr(ref params) => {
-				crypto::aes::decrypt(&derived_left_bits, &params.iv, &self.ciphertext, &mut *secret)
+				let from = 32 - self.ciphertext.len();
+				crypto::aes::decrypt(&derived_left_bits, &params.iv, &self.ciphertext, &mut (&mut *secret)[from..])
 			},
 		}

--- a/ethstore/src/dir/disk.rs
+++ b/ethstore/src/dir/disk.rs
@@ -76,15 +76,14 @@ impl DiskDirectory {
 			.map(|entry| entry.path())
 			.collect::<Vec<PathBuf>>();

-		let files: Result<Vec<_>, _> = paths.iter()
-			.map(fs::File::open)
-			.collect();
-
-		let files = try!(files);
-
-		files.into_iter()
-			.map(json::KeyFile::load)
-			.zip(paths.into_iter())
+		paths
+			.iter()
+			.map(|p| (
+				fs::File::open(p)
+					.map_err(Error::from)
+					.and_then(|r| json::KeyFile::load(r).map_err(|e| Error::Custom(format!("{:?}", e)))),
+				p
+			))
 			.map(|(file, path)| match file {
 				Ok(file) => Ok((path.clone(), SafeAccount::from_file(
 					file, path.file_name().and_then(|n| n.to_str()).expect("Keys have valid UTF8 names only.").to_owned()
--- a/ethstore/src/json/bytes.rs
+++ b/ethstore/src/json/bytes.rs
@@ -0,0 +1,58 @@
+use std::{ops, str};
+use serde::{Deserialize, Deserializer, Error, Serialize, Serializer};
+use rustc_serialize::hex::{ToHex, FromHex, FromHexError};
+
+#[derive(Debug, PartialEq)]
+pub struct Bytes(Vec<u8>);
+
+impl ops::Deref for Bytes {
+	type Target = [u8];
+
+	fn deref(&self) -> &Self::Target {
+		&self.0
+	}
+}
+
+impl Deserialize for Bytes {
+	fn deserialize<D>(deserializer: &mut D) -> Result<Self, D::Error>
+		where D: Deserializer
+	{
+		let s = try!(String::deserialize(deserializer));
+		let data = try!(s.from_hex().map_err(|e| Error::custom(format!("Invalid hex value {}", e))));
+		Ok(Bytes(data))
+	}
+}
+
+impl Serialize for Bytes {
+	fn serialize<S>(&self, serializer: &mut S) -> Result<(), S::Error>
+	where S: Serializer {
+		serializer.serialize_str(&self.0.to_hex())
+	}
+}
+
+impl str::FromStr for Bytes {
+	type Err = FromHexError;
+
+	fn from_str(s: &str) -> Result<Self, Self::Err> {
+		s.from_hex().map(Bytes)
+	}
+}
+
+impl From<&'static str> for Bytes {
+	fn from(s: &'static str) -> Self {
+		s.parse().expect(&format!("invalid string literal for {}: '{}'", stringify!(Self), s))
+	}
+}
+
+impl From<Vec<u8>> for Bytes {
+	fn from(v: Vec<u8>) -> Self {
+		Bytes(v)
+	}
+}
+
+impl From<Bytes> for Vec<u8> {
+	fn from(b: Bytes) -> Self {
+		b.0
+	}
+}
+
--- a/ethstore/src/json/crypto.rs
+++ b/ethstore/src/json/crypto.rs
@@ -17,12 +17,14 @@
 use serde::{Deserialize, Deserializer, Serialize, Serializer, Error};
 use serde::de::{Visitor, MapVisitor};
 use serde::ser;
-use super::{Cipher, CipherSer, CipherSerParams, Kdf, KdfSer, KdfSerParams, H256};
+use super::{Cipher, CipherSer, CipherSerParams, Kdf, KdfSer, KdfSerParams, H256, Bytes};
+
+pub type CipherText = Bytes;

 #[derive(Debug, PartialEq)]
 pub struct Crypto {
 	pub cipher: Cipher,
-	pub ciphertext: H256,
+	pub ciphertext: CipherText,
 	pub kdf: Kdf,
 	pub mac: H256,
 }
--- a/ethstore/src/json/hash.rs
+++ b/ethstore/src/json/hash.rs
@@ -14,9 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.

-use std::fmt;
-use std::ops;
-use std::str::FromStr;
+use std::{ops, fmt, str};
 use rustc_serialize::hex::{FromHex, ToHex};
 use serde::{Serialize, Serializer, Deserialize, Deserializer, Error as SerdeError};
 use serde::de::Visitor;
@@ -65,7 +63,7 @@ macro_rules! impl_hash {
 					type Value = $name;

 					fn visit_str<E>(&mut self, value: &str) -> Result<Self::Value, E> where E: SerdeError {
-						FromStr::from_str(value).map_err(SerdeError::custom)
+						value.parse().map_err(SerdeError::custom)
 					}

 					fn visit_string<E>(&mut self, value: String) -> Result<Self::Value, E> where E: SerdeError {
@@ -77,7 +75,7 @@ macro_rules! impl_hash {
 			}
 		}

-		impl FromStr for $name {
+		impl str::FromStr for $name {
 			type Err = Error;

 			fn from_str(value: &str) -> Result<Self, Self::Err> {
@@ -92,6 +90,12 @@ macro_rules! impl_hash {
 			}
 		}

+		impl From<&'static str> for $name {
+			fn from(s: &'static str) -> Self {
+				s.parse().expect(&format!("invalid string literal for {}: '{}'", stringify!(Self), s))
+			}
+		}
+
 		impl From<[u8; $size]> for $name {
 			fn from(bytes: [u8; $size]) -> Self {
 				$name(bytes)
--- a/ethstore/src/json/id.rs
+++ b/ethstore/src/json/id.rs
@@ -15,8 +15,7 @@
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.

 //! Universaly unique identifier.
-use std::str::FromStr;
-use std::fmt;
+use std::{fmt, str};
 use rustc_serialize::hex::{ToHex, FromHex};
 use serde::{Deserialize, Serialize, Deserializer, Serializer, Error as SerdeError};
 use serde::de::Visitor;
@@ -73,7 +72,7 @@ fn copy_into(from: &str, into: &mut [u8]) -> Result<(), Error> {
 	Ok(())
 }

-impl FromStr for UUID {
+impl str::FromStr for UUID {
 	type Err = Error;

 	fn from_str(s: &str) -> Result<Self, Self::Err> {
@@ -95,6 +94,12 @@ impl FromStr for UUID {
 	}
 }

+impl From<&'static str> for UUID {
+	fn from(s: &'static str) -> Self {
+		s.parse().expect(&format!("invalid string literal for {}: '{}'", stringify!(Self), s))
+	}
+}
+
 impl Serialize for UUID {
 	fn serialize<S>(&self, serializer: &mut S) -> Result<(), S::Error>
 	where S: Serializer {
@@ -116,7 +121,7 @@ impl Visitor for UUIDVisitor {
 	type Value = UUID;

 	fn visit_str<E>(&mut self, value: &str) -> Result<Self::Value, E> where E: SerdeError {
-		UUID::from_str(value).map_err(SerdeError::custom)
+		value.parse().map_err(SerdeError::custom)
 	}

 	fn visit_string<E>(&mut self, value: String) -> Result<Self::Value, E> where E: SerdeError {
@@ -126,19 +131,18 @@ impl Visitor for UUIDVisitor {

 #[cfg(test)]
 mod tests {
-	use std::str::FromStr;
 	use super::UUID;

 	#[test]
 	fn uuid_from_str() {
-		let uuid = UUID::from_str("3198bc9c-6672-5ab3-d995-4942343ae5b6").unwrap();
+		let uuid: UUID = "3198bc9c-6672-5ab3-d995-4942343ae5b6".into();
 		assert_eq!(uuid, UUID::from([0x31, 0x98, 0xbc, 0x9c, 0x66, 0x72, 0x5a, 0xb3, 0xd9, 0x95, 0x49, 0x42, 0x34, 0x3a, 0xe5, 0xb6]));
 	}

 	#[test]
 	fn uuid_from_and_to_str() {
 		let from = "3198bc9c-6672-5ab3-d995-4942343ae5b6";
-		let uuid = UUID::from_str(from).unwrap();
+		let uuid: UUID = from.into();
 		let to: String = uuid.into();
 		assert_eq!(from, &to);
 	}
--- a/ethstore/src/json/key_file.rs
+++ b/ethstore/src/json/key_file.rs
@@ -98,7 +98,7 @@ impl Visitor for KeyFileVisitor {
 				Some(KeyFileField::Version) => { version = Some(try!(visitor.visit_value())); }
 				Some(KeyFileField::Crypto) => { crypto = Some(try!(visitor.visit_value())); }
 				Some(KeyFileField::Address) => { address = Some(try!(visitor.visit_value())); }
-				Some(KeyFileField::Name) => { name = visitor.visit_value().ok(); }	// ignore anyhing that is not a string to be permissive. 
+				Some(KeyFileField::Name) => { name = visitor.visit_value().ok(); }	// ignore anyhing that is not a string to be permissive.
 				Some(KeyFileField::Meta) => { meta = visitor.visit_value().ok(); }	// ignore anyhing that is not a string to be permissive.
 				None => { break; }
 			}
@@ -153,7 +153,7 @@ impl KeyFile {
 mod tests {
 	use std::str::FromStr;
 	use serde_json;
-	use json::{KeyFile, UUID, Version, Crypto, Cipher, Aes128Ctr, Kdf, Scrypt, H128, H160, H256};
+	use json::{KeyFile, UUID, Version, Crypto, Cipher, Aes128Ctr, Kdf, Scrypt};

 	#[test]
 	fn basic_keyfile() {
@@ -185,20 +185,20 @@ mod tests {
 		let expected = KeyFile {
 			id: UUID::from_str("8777d9f6-7860-4b9b-88b7-0b57ee6b3a73").unwrap(),
 			version: Version::V3,
-			address: H160::from_str("6edddfc6349aff20bc6467ccf276c5b52487f7a8").unwrap(),
+			address: "6edddfc6349aff20bc6467ccf276c5b52487f7a8".into(),
 			crypto: Crypto {
 				cipher: Cipher::Aes128Ctr(Aes128Ctr {
-					iv: H128::from_str("b5a7ec855ec9e2c405371356855fec83").unwrap(),
+					iv: "b5a7ec855ec9e2c405371356855fec83".into(),
 				}),
-				ciphertext: H256::from_str("7203da0676d141b138cd7f8e1a4365f59cc1aa6978dc5443f364ca943d7cb4bc").unwrap(),
+				ciphertext: "7203da0676d141b138cd7f8e1a4365f59cc1aa6978dc5443f364ca943d7cb4bc".into(),
 				kdf: Kdf::Scrypt(Scrypt {
 					n: 262144,
 					dklen: 32,
 					p: 1,
 					r: 8,
-					salt: H256::from_str("1e8642fdf1f87172492c1412fc62f8db75d796cdfa9c53c3f2b11e44a2a1b209").unwrap(),
+					salt: "1e8642fdf1f87172492c1412fc62f8db75d796cdfa9c53c3f2b11e44a2a1b209".into(),
 				}),
-				mac: H256::from_str("46325c5d4e8c991ad2683d525c7854da387138b6ca45068985aa4959fa2b8c8f").unwrap(),
+				mac: "46325c5d4e8c991ad2683d525c7854da387138b6ca45068985aa4959fa2b8c8f".into(),
 			},
 			name: Some("Test".to_owned()),
 			meta: Some("{}".to_owned()),
@@ -234,22 +234,22 @@ mod tests {
 		}"#;

 		let expected = KeyFile {
-			id: UUID::from_str("8777d9f6-7860-4b9b-88b7-0b57ee6b3a73").unwrap(),
+			id: "8777d9f6-7860-4b9b-88b7-0b57ee6b3a73".into(),
 			version: Version::V3,
-			address: H160::from_str("6edddfc6349aff20bc6467ccf276c5b52487f7a8").unwrap(),
+			address: "6edddfc6349aff20bc6467ccf276c5b52487f7a8".into(),
 			crypto: Crypto {
 				cipher: Cipher::Aes128Ctr(Aes128Ctr {
-					iv: H128::from_str("b5a7ec855ec9e2c405371356855fec83").unwrap(),
+					iv: "b5a7ec855ec9e2c405371356855fec83".into(),
 				}),
-				ciphertext: H256::from_str("7203da0676d141b138cd7f8e1a4365f59cc1aa6978dc5443f364ca943d7cb4bc").unwrap(),
+				ciphertext: "7203da0676d141b138cd7f8e1a4365f59cc1aa6978dc5443f364ca943d7cb4bc".into(),
 				kdf: Kdf::Scrypt(Scrypt {
 					n: 262144,
 					dklen: 32,
 					p: 1,
 					r: 8,
-					salt: H256::from_str("1e8642fdf1f87172492c1412fc62f8db75d796cdfa9c53c3f2b11e44a2a1b209").unwrap(),
+					salt: "1e8642fdf1f87172492c1412fc62f8db75d796cdfa9c53c3f2b11e44a2a1b209".into(),
 				}),
-				mac: H256::from_str("46325c5d4e8c991ad2683d525c7854da387138b6ca45068985aa4959fa2b8c8f").unwrap(),
+				mac: "46325c5d4e8c991ad2683d525c7854da387138b6ca45068985aa4959fa2b8c8f".into(),
 			},
 			name: None,
 			meta: None,
@@ -262,22 +262,22 @@ mod tests {
 	#[test]
 	fn to_and_from_json() {
 		let file = KeyFile {
-			id: UUID::from_str("8777d9f6-7860-4b9b-88b7-0b57ee6b3a73").unwrap(),
+			id: "8777d9f6-7860-4b9b-88b7-0b57ee6b3a73".into(),
 			version: Version::V3,
-			address: H160::from_str("6edddfc6349aff20bc6467ccf276c5b52487f7a8").unwrap(),
+			address: "6edddfc6349aff20bc6467ccf276c5b52487f7a8".into(),
 			crypto: Crypto {
 				cipher: Cipher::Aes128Ctr(Aes128Ctr {
-					iv: H128::from_str("b5a7ec855ec9e2c405371356855fec83").unwrap(),
+					iv: "b5a7ec855ec9e2c405371356855fec83".into(),
 				}),
-				ciphertext: H256::from_str("7203da0676d141b138cd7f8e1a4365f59cc1aa6978dc5443f364ca943d7cb4bc").unwrap(),
+				ciphertext: "7203da0676d141b138cd7f8e1a4365f59cc1aa6978dc5443f364ca943d7cb4bc".into(),
 				kdf: Kdf::Scrypt(Scrypt {
 					n: 262144,
 					dklen: 32,
 					p: 1,
 					r: 8,
-					salt: H256::from_str("1e8642fdf1f87172492c1412fc62f8db75d796cdfa9c53c3f2b11e44a2a1b209").unwrap(),
+					salt: "1e8642fdf1f87172492c1412fc62f8db75d796cdfa9c53c3f2b11e44a2a1b209".into(),
 				}),
-				mac: H256::from_str("46325c5d4e8c991ad2683d525c7854da387138b6ca45068985aa4959fa2b8c8f").unwrap(),
+				mac: "46325c5d4e8c991ad2683d525c7854da387138b6ca45068985aa4959fa2b8c8f".into(),
 			},
 			name: Some("Test".to_owned()),
 			meta: None,
--- a/ethstore/src/json/mod.rs.in
+++ b/ethstore/src/json/mod.rs.in
@@ -1,3 +1,4 @@
+mod bytes;
 mod cipher;
 mod crypto;
 mod error;
@@ -8,8 +9,9 @@ mod key_file;
 mod presale;
 mod version;

+pub use self::bytes::Bytes;
 pub use self::cipher::{Cipher, CipherSer, CipherSerParams, Aes128Ctr};
-pub use self::crypto::Crypto;
+pub use self::crypto::{Crypto, CipherText};
 pub use self::error::Error;
 pub use self::hash::{H128, H160, H256};
 pub use self::id::UUID;
--- a/ethstore/src/json/presale.rs
+++ b/ethstore/src/json/presale.rs
@@ -1,30 +1,8 @@
 use std::io::Read;
-use std::ops::Deref;
 use serde_json;
-use serde::{Deserialize, Deserializer, Error};
-use rustc_serialize::hex::FromHex;
-use super::{H160};
+use super::{H160, Bytes};

-#[derive(Debug, PartialEq)]
-pub struct Encseed(Vec<u8>);
-
-impl Deref for Encseed {
-	type Target = [u8];
-
-	fn deref(&self) -> &Self::Target {
-		&self.0
-	}
-}
-
-impl Deserialize for Encseed {
-	fn deserialize<D>(deserializer: &mut D) -> Result<Self, D::Error>
-		where D: Deserializer
-	{
-		let s = try!(String::deserialize(deserializer));
-		let data = try!(s.from_hex().map_err(|e| Error::custom(format!("Invalid hex value {}", e))));
-		Ok(Encseed(data))
-	}
-}
+pub type Encseed = Bytes;

 #[derive(Debug, PartialEq, Deserialize)]
 pub struct PresaleWallet {
@@ -43,8 +21,7 @@ impl PresaleWallet {
 mod tests {
 	use std::str::FromStr;
 	use serde_json;
-	use rustc_serialize::hex::FromHex;
-	use json::{PresaleWallet, H160, Encseed};
+	use json::{PresaleWallet, H160};

 	#[test]
 	fn presale_wallet() {
@@ -57,7 +34,7 @@ mod tests {
 		} "#;

 		let expected = PresaleWallet {
-			encseed: Encseed("137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066".from_hex().unwrap()),
+			encseed: "137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066".into(),
 			address: H160::from_str("ede84640d1a1d3e06902048e67aa7db8d52c2ce1").unwrap(),
 		};

@@ -77,7 +54,7 @@ mod tests {
 		} "#;

 		let expected = PresaleWallet {
-			encseed: Encseed("137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0d".from_hex().unwrap()),
+			encseed: "137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dedb3bc0a9ac6c79b9c426c5878ca2c9d06ff42a23cb648312fc32ba83649de0928e066137103c28caeebbcea5d7f95edb97a289ded151b72159137cb7b2671f394f54cff8c121589dcb373e267225547b3c71cbdb54f6e48ec85cd549f96cf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0dcf0d".into(),
 			address: H160::from_str("ede84640d1a1d3e06902048e67aa7db8d52c2ce1").unwrap(),
 		};

--- a/ethstore/tests/api.rs
+++ b/ethstore/tests/api.rs
@@ -19,9 +19,8 @@ extern crate ethstore;

 mod util;

-use std::str::FromStr;
 use ethstore::{SecretStore, EthStore};
-use ethstore::ethkey::{Random, Generator, Secret, Address};
+use ethstore::ethkey::{Random, Generator, Secret, KeyPair, verify_address};
 use ethstore::dir::DiskDirectory;
 use util::TransientDir;

@@ -103,14 +102,21 @@ fn pat_path() -> &'static str {
 	}
 }

+fn ciphertext_path() -> &'static str {
+	match ::std::fs::metadata("ethstore") {
+		Ok(_) => "ethstore/tests/res/ciphertext",
+		Err(_) => "tests/res/ciphertext",
+	}
+}
+
 #[test]
 fn secret_store_laod_geth_files() {
 	let dir = DiskDirectory::at(test_path());
 	let store = EthStore::open(Box::new(dir)).unwrap();
 	assert_eq!(store.accounts().unwrap(), vec![
-		Address::from_str("3f49624084b67849c7b4e805c5988c21a430f9d9").unwrap(),
-		Address::from_str("5ba4dcf897e97c2bdf8315b9ef26c13c085988cf").unwrap(),
-		Address::from_str("63121b431a52f8043c16fcf0d1df9cb7b5f66649").unwrap(),
+		"3f49624084b67849c7b4e805c5988c21a430f9d9".parse().unwrap(),
+		"5ba4dcf897e97c2bdf8315b9ef26c13c085988cf".parse().unwrap(),
+		"63121b431a52f8043c16fcf0d1df9cb7b5f66649".parse().unwrap(),
 	]);
 }

@@ -119,9 +125,30 @@ fn secret_store_load_pat_files() {
 	let dir = DiskDirectory::at(pat_path());
 	let store = EthStore::open(Box::new(dir)).unwrap();
 	assert_eq!(store.accounts().unwrap(), vec![
-		Address::from_str("3f49624084b67849c7b4e805c5988c21a430f9d9").unwrap(),
-		Address::from_str("5ba4dcf897e97c2bdf8315b9ef26c13c085988cf").unwrap(),
+		"3f49624084b67849c7b4e805c5988c21a430f9d9".parse().unwrap(),
+		"5ba4dcf897e97c2bdf8315b9ef26c13c085988cf".parse().unwrap(),
 	]);
 }

+#[test]
+fn test_decrypting_files_with_short_ciphertext() {
+	// 31e9d1e6d844bd3a536800ef8d8be6a9975db509, 30
+	let kp1 = KeyPair::from_secret("000081c29e8142bb6a81bef5a92bda7a8328a5c85bb2f9542e76f9b0f94fc018".parse().unwrap()).unwrap();
+	// d1e64e5480bfaf733ba7d48712decb8227797a4e , 31
+	let kp2 = KeyPair::from_secret("00fa7b3db73dc7dfdf8c5fbdb796d741e4488628c41fc4febd9160a866ba0f35".parse().unwrap()).unwrap();
+	let dir = DiskDirectory::at(ciphertext_path());
+	let store = EthStore::open(Box::new(dir)).unwrap();
+	let accounts = store.accounts().unwrap();
+	assert_eq!(accounts, vec![
+		"31e9d1e6d844bd3a536800ef8d8be6a9975db509".parse().unwrap(),
+		"d1e64e5480bfaf733ba7d48712decb8227797a4e".parse().unwrap(),
+	]);

+	let message = Default::default();
+
+	let s1 = store.sign(&accounts[0], "foo", &message).unwrap();
+	let s2 = store.sign(&accounts[1], "foo", &message).unwrap();
+	assert!(verify_address(&accounts[0], &s1, &message).unwrap());
+	assert!(verify_address(&kp1.address(), &s1, &message).unwrap());
+	assert!(verify_address(&kp2.address(), &s2, &message).unwrap());
+}
--- a/ethstore/tests/res/ciphertext/30.json
+++ b/ethstore/tests/res/ciphertext/30.json
@@ -0,0 +1,21 @@
+{
+	"address" : "31e9d1e6d844bd3a536800ef8d8be6a9975db509",
+	"crypto" : {
+		"cipher" : "aes-128-ctr",
+		"cipherparams" : {
+			"iv" : "3ca92af36ad7c2cd92454c59cea5ef00"
+		},
+		"ciphertext" : "108b7d34f3442fc26ab1ab90ca91476ba6bfa8c00975a49ef9051dc675aa",
+		"kdf" : "scrypt",
+		"kdfparams" : {
+			"dklen" : 32,
+			"n" : 2,
+			"r" : 8,
+			"p" : 1,
+			"salt" : "d0769e608fb86cda848065642a9c6fa046845c928175662b8e356c77f914cd3b"
+		},
+		"mac" : "75d0e6759f7b3cefa319c3be41680ab6beea7d8328653474bd06706d4cc67420"
+	},
+	"id" : "a37e1559-5955-450d-8075-7b8931b392b2",
+	"version" : 3
+}
--- a/ethstore/tests/res/ciphertext/31.json
+++ b/ethstore/tests/res/ciphertext/31.json
@@ -0,0 +1,21 @@
+{
+	"address" : "d1e64e5480bfaf733ba7d48712decb8227797a4e",
+	"crypto" : {
+		"cipher" : "aes-128-ctr",
+		"cipherparams" : {
+			"iv" : "e0c41130a323adc1446fc82f724bca2f"
+		},
+		"ciphertext" : "9517cd5bdbe69076f9bf5057248c6c050141e970efa36ce53692d5d59a3984",
+		"kdf" : "scrypt",
+		"kdfparams" : {
+			"dklen" : 32,
+			"n" : 2,
+			"r" : 8,
+			"p" : 1,
+			"salt" : "711f816911c92d649fb4c84b047915679933555030b3552c1212609b38208c63"
+		},
+		"mac" : "d5e116151c6aa71470e67a7d42c9620c75c4d23229847dcc127794f0732b0db5"
+	},
+	"id" : "fecfc4ce-e956-48fd-953b-30f8b52ed66c",
+	"version" : 3
+}
--- a/logger/src/lib.rs
+++ b/logger/src/lib.rs
@@ -89,10 +89,10 @@ pub fn setup_log(config: &Config) -> Result<Arc<RotatingLogger>, String> {
 		let timestamp = time::strftime("%Y-%m-%d %H:%M:%S %Z", &time::now()).unwrap();

 		let with_color = if max_log_level() <= LogLevelFilter::Info {
-			format!("{}{}", Colour::Black.bold().paint(timestamp), record.args())
+			format!("{} {}", Colour::Black.bold().paint(timestamp), record.args())
 		} else {
 			let name = thread::current().name().map_or_else(Default::default, |x| format!("{}", Colour::Blue.bold().paint(x)));
-			format!("{}{} {} {}  {}", Colour::Black.bold().paint(timestamp), name, record.level(), record.target(), record.args())
+			format!("{} {} {} {}  {}", Colour::Black.bold().paint(timestamp), name, record.level(), record.target(), record.args())
 		};

 		let removed_color = kill_color(with_color.as_ref());
--- a/nsis/installer.nsi
+++ b/nsis/installer.nsi
@@ -4,7 +4,7 @@
 !define DESCRIPTION "Fast, light, robust Ethereum implementation"
 !define VERSIONMAJOR 1
 !define VERSIONMINOR 3
-!define VERSIONBUILD 1
+!define VERSIONBUILD 6

 !addplugindir .\

--- a/parity/cli.rs
+++ b/parity/cli.rs
@@ -193,7 +193,13 @@ Sealing/Mining Options:
  --extra-data STRING      Specify a custom extra-data for authored blocks, no
                           more than 32 characters.
  --tx-queue-size LIMIT    Maximum amount of transactions in the queue (waiting
-                           to be included in next block) [default: 1024].
+                           to be included in next block) [default: 2048].
+  --tx-queue-strategy S    Prioritization strategy used to order transactions
+                           in the queue. S may be:
+                           gas - Prioritize txs with low gas limit;
+                           gas_price - Prioritize txs with high gas price;
+                           gas_factor - Prioritize txs using gas price
+                           and gas limit ratio [default: gas_factor].
  --remove-solved          Move solved blocks from the work package queue
                           instead of cloning them. This gives a slightly
                           faster import speed, but means that extra solutions
@@ -372,12 +378,13 @@ pub struct Args {
 	pub flag_gas_cap: String,
 	pub flag_extra_data: Option<String>,
 	pub flag_tx_queue_size: usize,
+	pub flag_tx_queue_strategy: String,
 	pub flag_notify_work: Option<String>,
 	pub flag_logging: Option<String>,
 	pub flag_version: bool,
 	pub flag_from: String,
 	pub flag_to: String,
-  pub flag_at: String,
+	pub flag_at: String,
 	pub flag_format: Option<String>,
 	pub flag_jitvm: bool,
 	pub flag_log_file: Option<String>,
--- a/parity/configuration.rs
+++ b/parity/configuration.rs
@@ -25,7 +25,7 @@ use util::{Hashable, U256, Uint, Bytes, version_data, Secret, Address};
 use util::log::Colour;
 use ethsync::{NetworkConfiguration, is_valid_node_url};
 use ethcore::client::{VMType, Mode};
-use ethcore::miner::MinerOptions;
+use ethcore::miner::{MinerOptions, PrioritizationStrategy};

 use rpc::{IpcConfiguration, HttpConfiguration};
 use ethcore_rpc::NetworkSettings;
@@ -319,6 +319,15 @@ impl Configuration {
 		Ok(cfg)
 	}

+	fn transaction_queue_strategy(&self) -> Result<PrioritizationStrategy, String> {
+		match self.args.flag_tx_queue_strategy.as_str() {
+			"gas" => Ok(PrioritizationStrategy::GasAndGasPrice),
+			"gas_price" => Ok(PrioritizationStrategy::GasPriceOnly),
+			"gas_factor" => Ok(PrioritizationStrategy::GasFactorAndGasPrice),
+			_ => Err(format!("Invalid queue strategy: {}", self.args.flag_tx_queue_strategy)),
+		}
+	}
+
 	fn miner_options(&self) -> Result<MinerOptions, String> {
 		let reseal = try!(self.args.flag_reseal_on_txs.parse::<ResealPolicy>());

@@ -332,6 +341,7 @@ impl Configuration {
 				None => U256::max_value(),
 			},
 			tx_queue_size: self.args.flag_tx_queue_size,
+			tx_queue_strategy: try!(self.transaction_queue_strategy()),
 			pending_set: try!(to_pending_set(&self.args.flag_relay_set)),
 			reseal_min_period: Duration::from_millis(self.args.flag_reseal_min_period),
 			work_queue_size: self.args.flag_work_queue_size,
@@ -604,6 +614,7 @@ mod tests {
 	use docopt::Docopt;
 	use ethcore_rpc::NetworkSettings;
 	use ethcore::client::{VMType, BlockID};
+	use ethcore::miner::{MinerOptions, PrioritizationStrategy};
 	use helpers::{replace_home, default_network_config};
 	use run::RunCmd;
 	use blockchain::{BlockchainCmd, ImportBlockchain, ExportBlockchain, DataFormat};
@@ -777,6 +788,27 @@ mod tests {
 		}));
 	}

+	#[test]
+	fn should_parse_mining_options() {
+		// given
+		let mut mining_options = MinerOptions::default();
+
+		// when
+		let conf0 = parse(&["parity"]);
+		let conf1 = parse(&["parity", "--tx-queue-strategy", "gas_factor"]);
+		let conf2 = parse(&["parity", "--tx-queue-strategy", "gas_price"]);
+		let conf3 = parse(&["parity", "--tx-queue-strategy", "gas"]);
+
+		// then
+		assert_eq!(conf0.miner_options().unwrap(), mining_options);
+		mining_options.tx_queue_strategy = PrioritizationStrategy::GasFactorAndGasPrice;
+		assert_eq!(conf1.miner_options().unwrap(), mining_options);
+		mining_options.tx_queue_strategy = PrioritizationStrategy::GasPriceOnly;
+		assert_eq!(conf2.miner_options().unwrap(), mining_options);
+		mining_options.tx_queue_strategy = PrioritizationStrategy::GasAndGasPrice;
+		assert_eq!(conf3.miner_options().unwrap(), mining_options);
+	}
+
 	#[test]
 	fn should_parse_network_settings() {
 		// given
--- a/parity/dapps.rs
+++ b/parity/dapps.rs
@@ -19,11 +19,6 @@ use io::PanicHandler;
 use rpc_apis;
 use helpers::replace_home;

-#[cfg(feature = "dapps")]
-pub use ethcore_dapps::Server as WebappServer;
-#[cfg(not(feature = "dapps"))]
-pub struct WebappServer;
-
 #[derive(Debug, PartialEq, Clone)]
 pub struct Configuration {
 	pub enabled: bool,
@@ -77,6 +72,7 @@ pub fn new(configuration: Configuration, deps: Dependencies) -> Result<Option<We
 }

 pub use self::server::setup_dapps_server;
+pub use self::server::WebappServer;

 #[cfg(not(feature = "dapps"))]
 mod server {
--- a/parity/main.rs
+++ b/parity/main.rs
@@ -117,6 +117,8 @@ fn start() -> Result<String, String> {
 }

 fn main() {
+	// Always print backtrace on panic.
+	::std::env::set_var("RUST_BACKTRACE", "1");
 	// just redirect to the sync::main()
 	if std::env::args().nth(1).map_or(false, |arg| arg == "sync") {
 		sync::main();
--- a/parity/migration.rs
+++ b/parity/migration.rs
@@ -29,7 +29,7 @@ use ethcore::migrations::Extract;
 /// Database is assumed to be at default version, when no version file is found.
 const DEFAULT_VERSION: u32 = 5;
 /// Current version of database models.
-const CURRENT_VERSION: u32 = 9;
+const CURRENT_VERSION: u32 = 10;
 /// First version of the consolidated database.
 const CONSOLIDATION_VERSION: u32 = 9;
 /// Defines how many items are migrated to the new version of database at once.
@@ -140,7 +140,12 @@ pub fn default_migration_settings(compaction_profile: &CompactionProfile) -> Mig

 /// Migrations on the consolidated database.
 fn consolidated_database_migrations(compaction_profile: &CompactionProfile) -> Result<MigrationManager, Error> {
-	let manager = MigrationManager::new(default_migration_settings(compaction_profile));
+	let mut manager = MigrationManager::new(default_migration_settings(compaction_profile));
+	// this won't ever fire, because version will be already 9
+	// added because migration api should know that it should open database with 5 columns
+	try!(manager.add_migration(migrations::ToV9::new(Some(5), migrations::Extract::All)).map_err(|_| Error::MigrationImpossible));
+	// this will
+	try!(manager.add_migration(migrations::ToV10).map_err(|_| Error::MigrationImpossible));
 	Ok(manager)
 }

@@ -180,7 +185,6 @@ fn consolidate_database(
 	Ok(())
 }

-
 /// Migrates database at given position with given migration rules.
 fn migrate_database(version: u32, db_path: PathBuf, mut migrations: MigrationManager) -> Result<(), Error> {
 	// check if migration is needed
@@ -215,6 +219,12 @@ fn exists(path: &Path) -> bool {
 	fs::metadata(path).is_ok()
 }

+// in-place upgrades that do nothing when called repeatedly
+fn run_inplace_upgrades(path: &Path) -> Result<(), Error> {
+	try!(migrations::upgrade_account_bloom(path));
+	Ok(())
+}
+
 /// Migrates the database.
 pub fn migrate(path: &Path, pruning: Algorithm, compaction_profile: CompactionProfile) -> Result<(), Error> {
 	// read version file.
@@ -228,6 +238,7 @@ pub fn migrate(path: &Path, pruning: Algorithm, compaction_profile: CompactionPr

 	// We are in the latest version, yay!
 	if version == CURRENT_VERSION {
+		try!(run_inplace_upgrades(consolidated_database_path(path).as_path()));
 		return Ok(())
 	}

@@ -260,7 +271,12 @@ pub fn migrate(path: &Path, pruning: Algorithm, compaction_profile: CompactionPr
 	}

 	// update version file.
-	update_version(path)
+	try!(update_version(path));
+
+	// run any inplace migrations for the fully upgraded database
+	try!(run_inplace_upgrades(consolidated_database_path(path).as_path()));
+
+	Ok(())
 }

 /// Old migrations utilities
--- a/parity/params.rs
+++ b/parity/params.rs
@@ -215,7 +215,7 @@ impl Default for MinerExtras {
 			extra_data: version_data(),
 			gas_floor_target: U256::from(4_700_000),
 			gas_ceil_target: U256::from(6_283_184),
-			transactions_limit: 1024,
+			transactions_limit: 2048,
 		}
 	}
 }
--- a/parity/signer.rs
+++ b/parity/signer.rs
@@ -68,7 +68,7 @@ fn codes_path(path: String) -> PathBuf {

 pub fn new_token(path: String) -> Result<String, String> {
 	generate_new_token(path)
-		.map(|code| format!("This key code will authorise your System Signer UI: {}", Colour::White.bold().paint(code)))
+		.map(|code| format!("This key code will authorise your System Signer UI: {}", code))
 		.map_err(|err| format!("Error generating token: {:?}", err))
 }

--- a/rpc/Cargo.toml
+++ b/rpc/Cargo.toml
@@ -25,7 +25,7 @@ rustc-serialize = "0.3"
 transient-hashmap = "0.1"
 serde_macros = { version = "0.7.0", optional = true }
 clippy = { version = "0.0.80", optional = true}
-json-ipc-server = { git = "https://github.com/ethcore/json-ipc-server.git" }
+json-ipc-server = { git = "https://github.com/ethcore/json-ipc-server.git", branch = "beta" }
 ethcore-ipc = { path = "../ipc/rpc" }

 [build-dependencies]
--- a/rpc/src/v1/impls/eth.rs
+++ b/rpc/src/v1/impls/eth.rs
@@ -32,7 +32,7 @@ use util::rlp::{encode, decode, UntrustedRlp, View};
 use util::{FromHex, Mutex};
 use ethcore::account_provider::AccountProvider;
 use ethcore::client::{MiningBlockChainClient, BlockID, TransactionID, UncleID};
-use ethcore::header::Header as BlockHeader;
+use ethcore::header::{Header as BlockHeader, BlockNumber as EthBlockNumber};
 use ethcore::block::IsBlock;
 use ethcore::views::*;
 use ethcore::ethereum::Ethash;
@@ -193,8 +193,8 @@ impl<C, S: ?Sized, M, EM> EthClient<C, S, M, EM> where
 	}
 }

-pub fn pending_logs<M>(miner: &M, filter: &EthcoreFilter) -> Vec<Log> where M: MinerService {
-	let receipts = miner.pending_receipts();
+pub fn pending_logs<M>(miner: &M, best_block: EthBlockNumber, filter: &EthcoreFilter) -> Vec<Log> where M: MinerService {
+	let receipts = miner.pending_receipts(best_block);

 	let pending_logs = receipts.into_iter()
 		.flat_map(|(hash, r)| r.logs.into_iter().map(|l| (hash.clone(), l)).collect::<Vec<(H256, LogEntry)>>())
@@ -433,11 +433,14 @@ impl<C, S: ?Sized, M, EM> Eth for EthClient<C, S, M, EM> where
 		try!(self.active());
 		from_params::<(RpcH256,)>(params)
 			.and_then(|(hash,)| {
-				let miner = take_weak!(self.miner);
 				let hash: H256 = hash.into();
-				match miner.transaction(&hash) {
-					Some(pending_tx) => to_value(&Transaction::from(pending_tx)),
-					None => self.transaction(TransactionID::Hash(hash))
+				let miner = take_weak!(self.miner);
+				let client = take_weak!(self.client);
+				let maybe_tx = client.transaction(TransactionID::Hash(hash)).map(Transaction::from)
+					.or_else(|| miner.transaction(client.chain_info().best_block_number, &hash).map(Transaction::from));
+				match maybe_tx {
+					Some(t) => to_value(&t),
+					None => Ok(Value::Null),
 				}
 			})
 	}
@@ -459,8 +462,9 @@ impl<C, S: ?Sized, M, EM> Eth for EthClient<C, S, M, EM> where
 		from_params::<(RpcH256,)>(params)
 			.and_then(|(hash,)| {
 				let miner = take_weak!(self.miner);
+				let best_block = take_weak!(self.client).chain_info().best_block_number;
 				let hash: H256 = hash.into();
-				match (miner.pending_receipt(&hash), self.options.allow_pending_receipt_query) {
+				match (miner.pending_receipt(best_block, &hash), self.options.allow_pending_receipt_query) {
 					(Some(receipt), true) => to_value(&Receipt::from(receipt)),
 					_ => {
 						let client = take_weak!(self.client);
@@ -506,7 +510,8 @@ impl<C, S: ?Sized, M, EM> Eth for EthClient<C, S, M, EM> where
 					.collect::<Vec<Log>>();

 				if include_pending {
-					let pending = pending_logs(&*take_weak!(self.miner), &filter);
+					let best_block = take_weak!(self.client).chain_info().best_block_number;
+					let pending = pending_logs(&*take_weak!(self.miner), best_block, &filter);
 					logs.extend(pending);
 				}

--- a/rpc/src/v1/impls/eth_filter.rs
+++ b/rpc/src/v1/impls/eth_filter.rs
@@ -88,7 +88,8 @@ impl<C, M> EthFilter for EthFilterClient<C, M> where
 		try!(expect_no_params(params));

 		let mut polls = self.polls.lock();
-		let pending_transactions = take_weak!(self.miner).pending_transactions_hashes();
+		let best_block = take_weak!(self.client).chain_info().best_block_number;
+		let pending_transactions = take_weak!(self.miner).pending_transactions_hashes(best_block);
 		let id = polls.create_poll(PollFilter::PendingTransaction(pending_transactions));

 		to_value(&RpcU256::from(id))
@@ -118,7 +119,8 @@ impl<C, M> EthFilter for EthFilterClient<C, M> where
 						},
 						PollFilter::PendingTransaction(ref mut previous_hashes) => {
 							// get hashes of pending transactions
-							let current_hashes = take_weak!(self.miner).pending_transactions_hashes();
+							let current_number = client.chain_info().best_block_number;
+							let current_hashes = take_weak!(self.miner).pending_transactions_hashes(current_number);

 							let new_hashes =
 							{
@@ -159,7 +161,7 @@ impl<C, M> EthFilter for EthFilterClient<C, M> where

 							// additionally retrieve pending logs
 							if include_pending {
-								let pending_logs = pending_logs(&*take_weak!(self.miner), &filter);
+								let pending_logs = pending_logs(&*take_weak!(self.miner), current_number, &filter);

 								// remove logs about which client was already notified about
 								let new_pending_logs: Vec<_> = pending_logs.iter()
@@ -177,7 +179,6 @@ impl<C, M> EthFilter for EthFilterClient<C, M> where
 							// save the number of the next block as a first block from which
 							// we want to get logs
 							*block_number = current_number + 1;
-
 							to_value(&logs)
 						}
 					}
@@ -200,7 +201,8 @@ impl<C, M> EthFilter for EthFilterClient<C, M> where
 							.collect::<Vec<Log>>();

 						if include_pending {
-							logs.extend(pending_logs(&*take_weak!(self.miner), &filter));
+							let best_block = take_weak!(self.client).chain_info().best_block_number;
+							logs.extend(pending_logs(&*take_weak!(self.miner), best_block, &filter));
 						}

 						to_value(&logs)
--- a/rpc/src/v1/impls/ethcore.rs
+++ b/rpc/src/v1/impls/ethcore.rs
@@ -26,7 +26,7 @@ use ethcore::client::{MiningBlockChainClient};

 use jsonrpc_core::*;
 use v1::traits::Ethcore;
-use v1::types::{Bytes, U256, Peers, H160};
+use v1::types::{Bytes, U256, Peers, H160, Transaction};
 use v1::helpers::{errors, SigningQueue, ConfirmationsQueue, NetworkSettings};
 use v1::helpers::params::expect_no_params;

@@ -200,4 +200,11 @@ impl<C, M, S: ?Sized> Ethcore for EthcoreClient<C, M, S> where M: MinerService +
 			Some(ref queue) => to_value(&queue.len()),
 		}
 	}
+
+	fn pending_transactions(&self, params: Params) -> Result<Value, Error> {
+		try!(self.active());
+		try!(expect_no_params(params));
+
+		to_value(&take_weak!(self.miner).all_transactions().into_iter().map(Into::into).collect::<Vec<Transaction>>())
+	}
 }
--- a/rpc/src/v1/tests/eth.rs
+++ b/rpc/src/v1/tests/eth.rs
@@ -25,7 +25,7 @@ use ethcore::spec::{Genesis, Spec};
 use ethcore::block::Block;
 use ethcore::views::BlockView;
 use ethcore::ethereum;
-use ethcore::miner::{MinerOptions, GasPricer, MinerService, ExternalMiner, Miner, PendingSet};
+use ethcore::miner::{MinerOptions, GasPricer, MinerService, ExternalMiner, Miner, PendingSet, PrioritizationStrategy};
 use ethcore::account_provider::AccountProvider;
 use devtools::RandomTempPath;
 use util::Hashable;
@@ -59,6 +59,7 @@ fn miner_service(spec: &Spec, accounts: Arc<AccountProvider>) -> Arc<Miner> {
 			reseal_on_own_tx: true,
 			tx_queue_size: 1024,
 			tx_gas_limit: !U256::zero(),
+			tx_queue_strategy: PrioritizationStrategy::GasPriceOnly,
 			pending_set: PendingSet::SealingOrElseQueue,
 			reseal_min_period: Duration::from_secs(0),
 			work_queue_size: 50,
--- a/rpc/src/v1/tests/helpers/miner_service.rs
+++ b/rpc/src/v1/tests/helpers/miner_service.rs
@@ -21,6 +21,7 @@ use util::standard::*;
 use ethcore::error::{Error, CallError};
 use ethcore::client::{MiningBlockChainClient, Executed, CallAnalytics};
 use ethcore::block::{ClosedBlock, IsBlock};
+use ethcore::header::BlockNumber;
 use ethcore::transaction::SignedTransaction;
 use ethcore::receipt::{Receipt, RichReceipt};
 use ethcore::miner::{MinerService, MinerStatus, TransactionImportResult};
@@ -162,7 +163,7 @@ impl MinerService for TestMinerService {
 	}

 	/// Returns hashes of transactions currently in pending
-	fn pending_transactions_hashes(&self) -> Vec<H256> {
+	fn pending_transactions_hashes(&self, _best_block: BlockNumber) -> Vec<H256> {
 		vec![]
 	}

@@ -186,7 +187,7 @@ impl MinerService for TestMinerService {
 		Some(f(&open_block.close()))
 	}

-	fn transaction(&self, hash: &H256) -> Option<SignedTransaction> {
+	fn transaction(&self, _best_block: BlockNumber, hash: &H256) -> Option<SignedTransaction> {
 		self.pending_transactions.lock().get(hash).cloned()
 	}

@@ -194,13 +195,13 @@ impl MinerService for TestMinerService {
 		self.pending_transactions.lock().values().cloned().collect()
 	}

-	fn pending_transactions(&self) -> Vec<SignedTransaction> {
+	fn pending_transactions(&self, _best_block: BlockNumber) -> Vec<SignedTransaction> {
 		self.pending_transactions.lock().values().cloned().collect()
 	}

-	fn pending_receipt(&self, hash: &H256) -> Option<RichReceipt> {
+	fn pending_receipt(&self, _best_block: BlockNumber, hash: &H256) -> Option<RichReceipt> {
 		// Not much point implementing this since the logic is complex and the only thing it relies on is pending_receipts, which is already tested.
-		self.pending_receipts().get(hash).map(|r|
+		self.pending_receipts(0).get(hash).map(|r|
 			RichReceipt {
 				transaction_hash: Default::default(),
 				transaction_index: Default::default(),
@@ -212,7 +213,7 @@ impl MinerService for TestMinerService {
 		)
 	}

-	fn pending_receipts(&self) -> BTreeMap<H256, Receipt> {
+	fn pending_receipts(&self, _best_block: BlockNumber) -> BTreeMap<H256, Receipt> {
 		self.pending_receipts.lock().clone()
 	}

@@ -249,7 +250,7 @@ impl MinerService for TestMinerService {
 	}

 	fn code(&self, _chain: &MiningBlockChainClient, address: &Address) -> Option<Bytes> {
-		self.latest_closed_block.lock().as_ref().map_or(None, |b| b.block().fields().state.code(address).clone())
+		self.latest_closed_block.lock().as_ref().map_or(None, |b| b.block().fields().state.code(address).map(|c| (*c).clone()))
 	}

 }
--- a/rpc/src/v1/tests/mocked/ethcore.rs
+++ b/rpc/src/v1/tests/mocked/ethcore.rs
@@ -286,3 +286,18 @@ fn rpc_ethcore_unsigned_transactions_count_when_signer_disabled() {

 	assert_eq!(io.handle_request(request), Some(response.to_owned()));
 }
+
+#[test]
+fn rpc_ethcore_pending_transactions() {
+	let miner = miner_service();
+	let client = client_service();
+	let sync = sync_provider();
+	let net = network_service();
+	let io = IoHandler::new();
+	io.add_delegate(ethcore_client(&client, &miner, &sync, &net).to_delegate());
+
+	let request = r#"{"jsonrpc": "2.0", "method": "ethcore_pendingTransactions", "params":[], "id": 1}"#;
+	let response = r#"{"jsonrpc":"2.0","result":[],"id":1}"#;
+
+	assert_eq!(io.handle_request(request), Some(response.to_owned()));
+}
--- a/rpc/src/v1/traits/ethcore.rs
+++ b/rpc/src/v1/traits/ethcore.rs
@@ -70,6 +70,9 @@ pub trait Ethcore: Sized + Send + Sync + 'static {
 	/// Returns the value of the registrar for this network.
 	fn registry_address(&self, _: Params) -> Result<Value, Error>;

+	/// Returns all transactions in transaction queue.
+	fn pending_transactions(&self, _: Params) -> Result<Value, Error>;
+
 	/// Should be used to convert object to io delegate.
 	fn to_delegate(self) -> IoDelegate<Self> {
 		let mut delegate = IoDelegate::new(Arc::new(self));
@@ -90,6 +93,7 @@ pub trait Ethcore: Sized + Send + Sync + 'static {
 		delegate.add_method("ethcore_gasPriceStatistics", Ethcore::gas_price_statistics);
 		delegate.add_method("ethcore_unsignedTransactionsCount", Ethcore::unsigned_transactions_count);
 		delegate.add_method("ethcore_registryAddress", Ethcore::registry_address);
+		delegate.add_method("ethcore_pendingTransactions", Ethcore::pending_transactions);
 		delegate
 	}
 }
--- a/rpc/src/v1/types/bytes.rs
+++ b/rpc/src/v1/types/bytes.rs
@@ -70,10 +70,12 @@ impl Visitor for BytesVisitor {
 	type Value = Bytes;

 	fn visit_str<E>(&mut self, value: &str) -> Result<Self::Value, E> where E: Error {
-		if value.len() >= 2 && &value[0..2] == "0x" {
-			Ok(Bytes::new(FromHex::from_hex(&value[2..]).unwrap_or_else(|_| vec![])))
+		if value.is_empty() {
+			Ok(Bytes::new(Vec::new()))
+		} else if value.len() >= 2 && &value[0..2] == "0x" && value.len() & 1 == 0 {
+			Ok(Bytes::new(try!(FromHex::from_hex(&value[2..]).map_err(|_| Error::custom("invalid hex")))))
 		} else {
-			Err(Error::custom("invalid hex"))
+			Err(Error::custom("invalid format"))
 		}
 	}

@@ -95,5 +97,32 @@ mod tests {
 		let serialized = serde_json::to_string(&bytes).unwrap();
 		assert_eq!(serialized, r#""0x0123456789abcdef""#);
 	}
+
+	#[test]
+	fn test_bytes_deserialize() {
+		// TODO [ToDr] Uncomment when Mist starts sending correct data
+		// let bytes1: Result<Bytes, serde_json::Error> = serde_json::from_str(r#""""#);
+		let bytes2: Result<Bytes, serde_json::Error> = serde_json::from_str(r#""0x123""#);
+		let bytes3: Result<Bytes, serde_json::Error> = serde_json::from_str(r#""0xgg""#);
+
+		let bytes4: Bytes = serde_json::from_str(r#""0x""#).unwrap();
+		let bytes5: Bytes = serde_json::from_str(r#""0x12""#).unwrap();
+		let bytes6: Bytes = serde_json::from_str(r#""0x0123""#).unwrap();
+		let bytes7: Bytes = serde_json::from_str(r#""0x0123456789abcdef""#).unwrap();
+
+		// assert!(bytes1.is_err());
+		assert!(bytes2.is_err());
+		assert!(bytes3.is_err());
+		assert_eq!(bytes4, Bytes(vec![]));
+		assert_eq!(bytes5, Bytes(vec![0x12]));
+		assert_eq!(bytes6, Bytes(vec![0x1, 0x23]));
+		assert_eq!(bytes7, Bytes(vec![0x1, 0x23, 0x45,0x67,0x89, 0xab, 0xcd, 0xef]));
+	}
+
+	#[test]
+	fn test_bytes_lenient_against_the_spec_deserialize_for_empty_string_for_geth_compatibility() {
+		let deserialized: Bytes = serde_json::from_str(r#""""#).unwrap();
+		assert_eq!(deserialized, Bytes(Vec::new()));
+	}
 }

--- a/rpc/src/v1/types/filter.rs
+++ b/rpc/src/v1/types/filter.rs
@@ -83,9 +83,15 @@ impl Into<EthFilter> for Filter {
 					VariadicValue::Null => None,
 					VariadicValue::Single(t) => Some(vec![t.into()]),
 					VariadicValue::Multiple(t) => Some(t.into_iter().map(Into::into).collect())
-				}).filter_map(|m| m).collect()).into_iter();
-				vec![iter.next(), iter.next(), iter.next(), iter.next()]
-			}
+				}).collect()).into_iter();
+
+				vec![
+					iter.next().unwrap_or(None),
+					iter.next().unwrap_or(None),
+					iter.next().unwrap_or(None),
+					iter.next().unwrap_or(None)
+				]
+			},
 		}
 	}
 }
@@ -97,6 +103,8 @@ mod tests {
 	use util::hash::*;
 	use super::*;
 	use v1::types::BlockNumber;
+	use ethcore::filter::Filter as EthFilter;
+	use ethcore::client::BlockID;

 	#[test]
 	fn topic_deserialization() {
@@ -123,4 +131,31 @@ mod tests {
 			topics: None
 		});
 	}
+
+	#[test]
+	fn filter_conversion() {
+		let filter = Filter {
+			from_block: Some(BlockNumber::Earliest),
+			to_block: Some(BlockNumber::Latest),
+			address: Some(VariadicValue::Multiple(vec![])),
+			topics: Some(vec![
+				VariadicValue::Null,
+				VariadicValue::Single("000000000000000000000000a94f5374fce5edbc8e2a8697c15331677e6ebf0b".into()),
+				VariadicValue::Null,
+			]),
+		};
+
+		let eth_filter: EthFilter = filter.into();
+		assert_eq!(eth_filter, EthFilter {
+			from_block: BlockID::Earliest,
+			to_block: BlockID::Latest,
+			address: Some(vec![]),
+			topics: vec![
+				None,
+				Some(vec!["000000000000000000000000a94f5374fce5edbc8e2a8697c15331677e6ebf0b".into()]),
+				None,
+				None,
+			],
+		});
+	}
 }
--- a/rpc/src/v1/types/hash.rs
+++ b/rpc/src/v1/types/hash.rs
@@ -25,9 +25,10 @@ use util::{H64 as Eth64, H256 as EthH256, H520 as EthH520, H2048 as Eth2048, Add
 macro_rules! impl_hash {
 	($name: ident, $other: ident, $size: expr) => {
 		/// Hash serialization
-		#[derive(Eq)]
 		pub struct $name([u8; $size]);

+		impl Eq for $name { }
+
 		impl Default for $name {
 			fn default() -> Self {
 				$name([0; $size])
--- a/rpc/src/v1/types/uint.rs
+++ b/rpc/src/v1/types/uint.rs
@@ -23,9 +23,11 @@ use util::{U256 as EthU256, Uint};
 macro_rules! impl_uint {
 	($name: ident, $other: ident, $size: expr) => {
 		/// Uint serialization.
-		#[derive(Debug, Default, Clone, Copy, PartialEq, Eq, Hash)]
+		#[derive(Debug, Default, Clone, Copy, PartialEq, Hash)]
 		pub struct $name($other);

+		impl Eq for $name { }
+
 		impl<T> From<T> for $name where $other: From<T> {
 			fn from(o: T) -> Self {
 				$name($other::from(o))
--- a/sync/src/api.rs
+++ b/sync/src/api.rs
@@ -15,9 +15,10 @@
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.

 use std::sync::Arc;
+use std::collections::HashMap;
 use network::{NetworkProtocolHandler, NetworkService, NetworkContext, PeerId,
 	NetworkConfiguration as BasicNetworkConfiguration, NonReservedPeerMode, NetworkError};
-use util::{U256, H256, Secret, Populatable};
+use util::{U256, H256, Secret, Populatable, Bytes};
 use io::{TimerToken};
 use ethcore::client::{BlockChainClient, ChainNotify};
 use ethcore::header::BlockNumber;
@@ -78,7 +79,11 @@ impl EthSync {
 		let service = try!(NetworkService::new(try!(network_config.into_basic())));
 		let sync = Arc::new(EthSync{
 			network: service,
-			handler: Arc::new(SyncProtocolHandler { sync: RwLock::new(chain_sync), chain: chain }),
+			handler: Arc::new(SyncProtocolHandler {
+				sync: RwLock::new(chain_sync),
+				chain: chain,
+				overlay: RwLock::new(HashMap::new()),
+			}),
 		});

 		Ok(sync)
@@ -99,6 +104,8 @@ struct SyncProtocolHandler {
 	chain: Arc<BlockChainClient>,
 	/// Sync strategy
 	sync: RwLock<ChainSync>,
+	/// Chain overlay used to cache data such as fork block.
+	overlay: RwLock<HashMap<BlockNumber, Bytes>>,
 }

 impl NetworkProtocolHandler for SyncProtocolHandler {
@@ -107,20 +114,20 @@ impl NetworkProtocolHandler for SyncProtocolHandler {
 	}

 	fn read(&self, io: &NetworkContext, peer: &PeerId, packet_id: u8, data: &[u8]) {
-		ChainSync::dispatch_packet(&self.sync, &mut NetSyncIo::new(io, &*self.chain), *peer, packet_id, data);
+		ChainSync::dispatch_packet(&self.sync, &mut NetSyncIo::new(io, &*self.chain, &self.overlay), *peer, packet_id, data);
 	}

 	fn connected(&self, io: &NetworkContext, peer: &PeerId) {
-		self.sync.write().on_peer_connected(&mut NetSyncIo::new(io, &*self.chain), *peer);
+		self.sync.write().on_peer_connected(&mut NetSyncIo::new(io, &*self.chain, &self.overlay), *peer);
 	}

 	fn disconnected(&self, io: &NetworkContext, peer: &PeerId) {
-		self.sync.write().on_peer_aborting(&mut NetSyncIo::new(io, &*self.chain), *peer);
+		self.sync.write().on_peer_aborting(&mut NetSyncIo::new(io, &*self.chain, &self.overlay), *peer);
 	}

 	fn timeout(&self, io: &NetworkContext, _timer: TimerToken) {
-		self.sync.write().maintain_peers(&mut NetSyncIo::new(io, &*self.chain));
-		self.sync.write().maintain_sync(&mut NetSyncIo::new(io, &*self.chain));
+		self.sync.write().maintain_peers(&mut NetSyncIo::new(io, &*self.chain, &self.overlay));
+		self.sync.write().maintain_sync(&mut NetSyncIo::new(io, &*self.chain, &self.overlay));
 	}
 }

@@ -134,7 +141,7 @@ impl ChainNotify for EthSync {
 		_duration: u64)
 	{
 		self.network.with_context(ETH_PROTOCOL, |context| {
-			let mut sync_io = NetSyncIo::new(context, &*self.handler.chain);
+			let mut sync_io = NetSyncIo::new(context, &*self.handler.chain, &self.handler.overlay);
 			self.handler.sync.write().chain_new_blocks(
 				&mut sync_io,
 				&imported,
@@ -203,7 +210,7 @@ impl ManageNetwork for EthSync {

 	fn stop_network(&self) {
 		self.network.with_context(ETH_PROTOCOL, |context| {
-			let mut sync_io = NetSyncIo::new(context, &*self.handler.chain);
+			let mut sync_io = NetSyncIo::new(context, &*self.handler.chain, &self.handler.overlay);
 			self.handler.sync.write().abort(&mut sync_io);
 		});
 		self.stop();
--- a/sync/src/blocks.rs
+++ b/sync/src/blocks.rs
@@ -18,7 +18,7 @@ use util::*;
 use network::NetworkError;
 use ethcore::header::{ Header as BlockHeader};

-known_heap_size!(0, HeaderId, SyncBlock);
+known_heap_size!(0, HeaderId);

 /// Block data with optional body.
 struct SyncBlock {
@@ -26,6 +26,12 @@ struct SyncBlock {
 	body: Option<Bytes>,
 }

+impl HeapSizeOf for SyncBlock {
+	fn heap_size_of_children(&self) -> usize {
+		self.header.heap_size_of_children() + self.body.heap_size_of_children()
+	}
+}
+
 /// Used to identify header by transactions and uncles hashes
 #[derive(Eq, PartialEq, Hash)]
 struct HeaderId {
@@ -177,8 +183,8 @@ impl BlockCollection {
 		{
 			let mut blocks = Vec::new();
 			let mut head = self.head;
-			while head.is_some() {
-				head = self.parents.get(&head.unwrap()).cloned();
+			while let Some(h) = head {
+				head = self.parents.get(&h).cloned();
 				if let Some(head) = head {
 					match self.blocks.get(&head) {
 						Some(block) if block.body.is_some() => {
@@ -194,7 +200,7 @@ impl BlockCollection {
 			for block in blocks.drain(..) {
 				let mut block_rlp = RlpStream::new_list(3);
 				block_rlp.append_raw(&block.header, 1);
-				let body = Rlp::new(block.body.as_ref().unwrap()); // incomplete blocks are filtered out in the loop above
+				let body = Rlp::new(block.body.as_ref().expect("blocks contains only full blocks; qed"));
 				block_rlp.append_raw(body.at(0).as_raw(), 1);
 				block_rlp.append_raw(body.at(1).as_raw(), 1);
 				drained.push(block_rlp.out());
@@ -218,10 +224,14 @@ impl BlockCollection {
 		self.blocks.contains_key(hash)
 	}

-	/// Return heap size.
+	/// Return used heap size.
 	pub fn heap_size(&self) -> usize {
-		//TODO: other collections
-		self.blocks.heap_size_of_children()
+		self.heads.heap_size_of_children()
+			+ self.blocks.heap_size_of_children()
+			+ self.parents.heap_size_of_children()
+			+ self.header_ids.heap_size_of_children()
+			+ self.downloading_headers.heap_size_of_children()
+			+ self.downloading_bodies.heap_size_of_children()
 	}

 	/// Check if given block hash is marked as being downloaded.
--- a/sync/src/chain.rs
+++ b/sync/src/chain.rs
@@ -89,7 +89,6 @@

 use util::*;
 use network::*;
-use std::mem::{replace};
 use ethcore::views::{HeaderView, BlockView};
 use ethcore::header::{BlockNumber, Header as BlockHeader};
 use ethcore::client::{BlockChainClient, BlockStatus, BlockID, BlockChainInfo, BlockImportError};
@@ -121,6 +120,7 @@ const MAX_ROUND_PARENTS: usize = 32;
 const MAX_NEW_HASHES: usize = 64;
 const MAX_TX_TO_IMPORT: usize = 512;
 const MAX_NEW_BLOCK_AGE: BlockNumber = 20;
+const MAX_TRANSACTION_SIZE: usize = 300*1024;

 const STATUS_PACKET: u8 = 0x00;
 const NEW_BLOCK_HASHES_PACKET: u8 = 0x01;
@@ -137,7 +137,7 @@ const GET_RECEIPTS_PACKET: u8 = 0x0f;
 const RECEIPTS_PACKET: u8 = 0x10;

 const HEADERS_TIMEOUT_SEC: f64 = 15f64;
-const BODIES_TIMEOUT_SEC: f64 = 5f64;
+const BODIES_TIMEOUT_SEC: f64 = 10f64;
 const FORK_HEADER_TIMEOUT_SEC: f64 = 3f64;

 #[derive(Copy, Clone, Eq, PartialEq, Debug)]
@@ -229,8 +229,6 @@ struct PeerInfo {
 	network_id: U256,
 	/// Peer best block hash
 	latest_hash: H256,
-	/// Peer best block number if known
-	latest_number: Option<BlockNumber>,
 	/// Peer total difficulty if known
 	difficulty: Option<U256>,
 	/// Type of data currenty being requested from peer.
@@ -359,6 +357,8 @@ impl ChainSync {
 		}
 		self.syncing_difficulty = From::from(0u64);
 		self.state = SyncState::Idle;
+		// Reactivate peers only if some progress has been made
+		// since the last sync round of if starting fresh.
 		self.active_peers = self.peers.keys().cloned().collect();
 	}

@@ -370,7 +370,8 @@ impl ChainSync {
 		self.continue_sync(io);
 	}

-	/// Remove peer from active peer set
+	/// Remove peer from active peer set. Peer will be reactivated on the next sync
+	/// round.
 	fn deactivate_peer(&mut self, io: &mut SyncIo, peer_id: PeerId) {
 		trace!(target: "sync", "Deactivating peer {}", peer_id);
 		self.active_peers.remove(&peer_id);
@@ -400,7 +401,6 @@ impl ChainSync {
 			network_id: try!(r.val_at(1)),
 			difficulty: Some(try!(r.val_at(2))),
 			latest_hash: try!(r.val_at(3)),
-			latest_number: None,
 			genesis: try!(r.val_at(4)),
 			asking: PeerAsking::Nothing,
 			asking_blocks: Vec::new(),
@@ -433,7 +433,11 @@ impl ChainSync {
 		}

 		self.peers.insert(peer_id.clone(), peer);
-		self.active_peers.insert(peer_id.clone());
+		// Don't activate peer immediatelly when searching for common block.
+		// Let the current sync round complete first.
+		if self.state != SyncState::ChainHead {
+			self.active_peers.insert(peer_id.clone());
+		}
 		debug!(target: "sync", "Connected {}:{}", peer_id, io.peer_info(peer_id));
 		if let Some((fork_block, _)) = self.fork_block {
 			self.request_headers_by_number(io, peer_id, fork_block, 1, 0, false, PeerAsking::ForkHeader);
@@ -449,7 +453,9 @@ impl ChainSync {
 		let confirmed = match self.peers.get_mut(&peer_id) {
 			Some(ref mut peer) if peer.asking == PeerAsking::ForkHeader => {
 				let item_count = r.item_count();
-				if item_count == 0 || (item_count == 1 && try!(r.at(0)).as_raw().sha3() == self.fork_block.unwrap().1) {
+				let (fork_number, fork_hash) = self.fork_block.expect("ForkHeader request is sent only fork block is Some; qed").clone();
+				let header = try!(r.at(0)).as_raw();
+				if item_count == 0 || (item_count == 1 && header.sha3() == fork_hash) {
 					peer.asking = PeerAsking::Nothing;
 					if item_count == 0 {
 						trace!(target: "sync", "{}: Chain is too short to confirm the block", peer_id);
@@ -457,6 +463,9 @@ impl ChainSync {
 					} else {
 						trace!(target: "sync", "{}: Confirmed peer", peer_id);
 						peer.confirmation = ForkConfirmation::Confirmed;
+						if !io.chain_overlay().read().contains_key(&fork_number) {
+							io.chain_overlay().write().insert(fork_number, header.to_vec());
+						}
 					}
 					true
 				} else {
@@ -515,7 +524,7 @@ impl ChainSync {
 				continue;
 			}

-			if self.highest_block == None || number > self.highest_block.unwrap() {
+			if self.highest_block.as_ref().map_or(true,  |n| number > *n) {
 				self.highest_block = Some(number);
 			}
 			let hash = info.hash();
@@ -547,9 +556,9 @@ impl ChainSync {
 		}

 		if headers.is_empty() {
-			// Peer does not have any new subchain heads, deactivate it nd try with another
+			// Peer does not have any new subchain heads, deactivate it and try with another.
 			trace!(target: "sync", "{} Disabled for no data", peer_id);
-			io.disable_peer(peer_id);
+			self.deactivate_peer(io, peer_id);
 		}
 		match self.state {
 			SyncState::ChainHead => {
@@ -628,9 +637,9 @@ impl ChainSync {
 		}
 		let mut unknown = false;
 		{
-			let peer = self.peers.get_mut(&peer_id).unwrap();
-			peer.latest_hash = header.hash();
-			peer.latest_number = Some(header.number());
+			if let Some(ref mut peer) = self.peers.get_mut(&peer_id) {
+				peer.latest_hash = header.hash();
+			}
 		}
 		if self.last_imported_block > header.number() && self.last_imported_block - header.number() > MAX_NEW_BLOCK_AGE {
 			trace!(target: "sync", "Ignored ancient new block {:?}", h);
@@ -723,9 +732,9 @@ impl ChainSync {
 					new_hashes.push(hash.clone());
 					if number > max_height {
 						trace!(target: "sync", "New unknown block hash {:?}", hash);
-						let peer = self.peers.get_mut(&peer_id).unwrap();
-						peer.latest_hash = hash.clone();
-						peer.latest_number = Some(number);
+						if let Some(ref mut peer) = self.peers.get_mut(&peer_id) {
+							peer.latest_hash = hash.clone();
+						}
 						max_height = number;
 					}
 				},
@@ -802,15 +811,18 @@ impl ChainSync {
 			return;
 		}
 		let (peer_latest, peer_difficulty) = {
-			let peer = self.peers.get_mut(&peer_id).unwrap();
-			if peer.asking != PeerAsking::Nothing || !peer.can_sync() {
+			if let Some(ref mut peer) = self.peers.get_mut(&peer_id) {
+				if peer.asking != PeerAsking::Nothing || !peer.can_sync() {
+					return;
+				}
+				if self.state == SyncState::Waiting {
+					trace!(target: "sync", "Waiting for the block queue");
+					return;
+				}
+				(peer.latest_hash.clone(), peer.difficulty.clone())
+			} else {
 				return;
 			}
-			if self.state == SyncState::Waiting {
-				trace!(target: "sync", "Waiting for the block queue");
-				return;
-			}
-			(peer.latest_hash.clone(), peer.difficulty.clone())
 		};
 		let chain_info = io.chain().chain_info();
 		let td = chain_info.pending_total_difficulty;
@@ -887,35 +899,40 @@ impl ChainSync {
 		// check to see if we need to download any block bodies first
 		let needed_bodies = self.blocks.needed_bodies(MAX_BODIES_TO_REQUEST, ignore_others);
 		if !needed_bodies.is_empty() {
-			replace(&mut self.peers.get_mut(&peer_id).unwrap().asking_blocks, needed_bodies.clone());
+			if let Some(ref mut peer) = self.peers.get_mut(&peer_id) {
+				peer.asking_blocks = needed_bodies.clone();
+			}
 			self.request_bodies(io, peer_id, needed_bodies);
 			return;
 		}

 		// find subchain to download
 		if let Some((h, count)) = self.blocks.needed_headers(MAX_HEADERS_TO_REQUEST, ignore_others) {
-			replace(&mut self.peers.get_mut(&peer_id).unwrap().asking_blocks, vec![h.clone()]);
+			if let Some(ref mut peer) = self.peers.get_mut(&peer_id) {
+				peer.asking_blocks = vec![h.clone()];
+			}
 			self.request_headers_by_hash(io, peer_id, &h, count, 0, false, PeerAsking::BlockHeaders);
 		}
 	}

 	/// Clear all blocks/headers marked as being downloaded by a peer.
 	fn clear_peer_download(&mut self, peer_id: PeerId) {
-		let peer = self.peers.get_mut(&peer_id).unwrap();
-		match peer.asking {
-			PeerAsking::BlockHeaders | PeerAsking::Heads => {
-				for b in &peer.asking_blocks {
-					self.blocks.clear_header_download(b);
-				}
-			},
-			PeerAsking::BlockBodies => {
-				for b in &peer.asking_blocks {
-					self.blocks.clear_body_download(b);
-				}
-			},
-			_ => (),
+		if let Some(ref mut peer) = self.peers.get_mut(&peer_id) {
+			match peer.asking {
+				PeerAsking::BlockHeaders | PeerAsking::Heads => {
+					for b in &peer.asking_blocks {
+						self.blocks.clear_header_download(b);
+					}
+				},
+				PeerAsking::BlockBodies => {
+					for b in &peer.asking_blocks {
+						self.blocks.clear_body_download(b);
+					}
+				},
+				_ => (),
+			}
+			peer.asking_blocks.clear();
 		}
-		peer.asking_blocks.clear();
 	}

 	fn block_imported(&mut self, hash: &H256, number: BlockNumber, parent: &H256) {
@@ -1024,30 +1041,34 @@ impl ChainSync {

 	/// Reset peer status after request is complete.
 	fn reset_peer_asking(&mut self, peer_id: PeerId, asking: PeerAsking) -> bool {
-		let peer = self.peers.get_mut(&peer_id).unwrap();
-		peer.expired = false;
-		if peer.asking != asking {
-			trace!(target:"sync", "Asking {:?} while expected {:?}", peer.asking, asking);
-			peer.asking = PeerAsking::Nothing;
+		if let Some(ref mut peer) = self.peers.get_mut(&peer_id) {
+			peer.expired = false;
+			if peer.asking != asking {
+				trace!(target:"sync", "Asking {:?} while expected {:?}", peer.asking, asking);
+				peer.asking = PeerAsking::Nothing;
+				false
+			}
+			else {
+				peer.asking = PeerAsking::Nothing;
+				true
+			}
+		} else {
 			false
 		}
-		else {
-			peer.asking = PeerAsking::Nothing;
-			true
-		}
 	}

 	/// Generic request sender
 	fn send_request(&mut self, sync: &mut SyncIo, peer_id: PeerId, asking: PeerAsking,  packet_id: PacketId, packet: Bytes) {
-		let peer = self.peers.get_mut(&peer_id).unwrap();
-		if peer.asking != PeerAsking::Nothing {
-			warn!(target:"sync", "Asking {:?} while requesting {:?}", peer.asking, asking);
-		}
-		peer.asking = asking;
-		peer.ask_time = time::precise_time_s();
-		if let Err(e) = sync.send(peer_id, packet_id, packet) {
-			debug!(target:"sync", "Error sending request: {:?}", e);
-			sync.disable_peer(peer_id);
+		if let Some(ref mut peer) = self.peers.get_mut(&peer_id) {
+			if peer.asking != PeerAsking::Nothing {
+				warn!(target:"sync", "Asking {:?} while requesting {:?}", peer.asking, asking);
+			}
+			peer.asking = asking;
+			peer.ask_time = time::precise_time_s();
+			if let Err(e) = sync.send(peer_id, packet_id, packet) {
+				debug!(target:"sync", "Error sending request: {:?}", e);
+				sync.disable_peer(peer_id);
+			}
 		}
 	}

@@ -1074,7 +1095,12 @@ impl ChainSync {
 		item_count = min(item_count, MAX_TX_TO_IMPORT);
 		let mut transactions = Vec::with_capacity(item_count);
 		for i in 0 .. item_count {
-			let tx = try!(r.at(i)).as_raw().to_vec();
+			let rlp = try!(r.at(i));
+			if rlp.as_raw().len() > MAX_TRANSACTION_SIZE {
+				debug!("Skipped oversized transaction of {} bytes", rlp.as_raw().len());
+				continue;
+			}
+			let tx = rlp.as_raw().to_vec();
 			transactions.push(tx);
 		}
 		io.chain().queue_transactions(transactions);
@@ -1135,8 +1161,13 @@ impl ChainSync {
 		let mut count = 0;
 		let mut data = Bytes::new();
 		let inc = (skip + 1) as BlockNumber;
+		let overlay = io.chain_overlay().read();
 		while number <= last && count < max_count {
-			if let Some(mut hdr) = io.chain().block_header(BlockID::Number(number)) {
+			if let Some(hdr) = overlay.get(&number) {
+				trace!(target: "sync", "{}: Returning cached fork header", peer_id);
+				data.extend(hdr);
+				count += 1;
+			} else if let Some(mut hdr) = io.chain().block_header(BlockID::Number(number)) {
 				data.append(&mut hdr);
 				count += 1;
 			}
@@ -1336,8 +1367,10 @@ impl ChainSync {
 						let mut rlp_stream = RlpStream::new_list(blocks.len());
 						for block_hash in  blocks {
 							let mut hash_rlp = RlpStream::new_list(2);
-							let number = HeaderView::new(&chain.block_header(BlockID::Hash(block_hash.clone()))
-								.expect("chain.tree_route and chain.find_uncles only return hahses of blocks that are in the blockchain. qed.")).number();
+							let number = match chain.block_header(BlockID::Hash(block_hash.clone())) {
+								Some(header) => HeaderView::new(&header).number(),
+								_ => return None,
+							};
 							hash_rlp.append(&block_hash);
 							hash_rlp.append(&number);
 							rlp_stream.append_raw(hash_rlp.as_raw(), 1);
@@ -1353,7 +1386,7 @@ impl ChainSync {
 	/// creates latest block rlp for the given client
 	fn create_latest_block_rlp(chain: &BlockChainClient) -> Bytes {
 		let mut rlp_stream = RlpStream::new_list(2);
-		rlp_stream.append_raw(&chain.block(BlockID::Hash(chain.chain_info().best_block_hash)).unwrap(), 1);
+		rlp_stream.append_raw(&chain.block(BlockID::Hash(chain.chain_info().best_block_hash)).expect("Best block always exists"), 1);
 		rlp_stream.append(&chain.chain_info().total_difficulty);
 		rlp_stream.out()
 	}
@@ -1367,25 +1400,23 @@ impl ChainSync {
 	}

 	/// returns peer ids that have less blocks than our chain
-	fn get_lagging_peers(&mut self, chain_info: &BlockChainInfo, io: &SyncIo) -> Vec<(PeerId, BlockNumber)> {
+	fn get_lagging_peers(&mut self, chain_info: &BlockChainInfo, io: &SyncIo) -> Vec<PeerId> {
 		let latest_hash = chain_info.best_block_hash;
-		let latest_number = chain_info.best_block_number;
 		self.peers.iter_mut().filter_map(|(&id, ref mut peer_info)|
 			match io.chain().block_status(BlockID::Hash(peer_info.latest_hash.clone())) {
 				BlockStatus::InChain => {
-					if peer_info.latest_number.is_none() {
-						peer_info.latest_number = Some(HeaderView::new(&io.chain().block_header(BlockID::Hash(peer_info.latest_hash.clone())).unwrap()).number());
+					if peer_info.latest_hash != latest_hash {
+						Some(id)
+					} else {
+						None
 					}
-					if peer_info.latest_hash != latest_hash && latest_number > peer_info.latest_number.unwrap() {
-						Some((id, peer_info.latest_number.unwrap()))
-					} else { None }
 				},
 				_ => None
 			})
 			.collect::<Vec<_>>()
 	}

-	fn select_random_lagging_peers(&mut self, peers: &[(PeerId, BlockNumber)]) -> Vec<(PeerId, BlockNumber)> {
+	fn select_random_lagging_peers(&mut self, peers: &[PeerId]) -> Vec<PeerId> {
 		use rand::Rng;
 		// take sqrt(x) peers
 		let mut peers = peers.to_vec();
@@ -1398,46 +1429,42 @@ impl ChainSync {
 	}

 	/// propagates latest block to lagging peers
-	fn propagate_blocks(&mut self, chain_info: &BlockChainInfo, io: &mut SyncIo, sealed: &[H256], peers: &[(PeerId, BlockNumber)]) -> usize {
+	fn propagate_blocks(&mut self, chain_info: &BlockChainInfo, io: &mut SyncIo, sealed: &[H256], peers: &[PeerId]) -> usize {
 		trace!(target: "sync", "Sending NewBlocks to {:?}", peers);
 		let mut sent = 0;
-		for &(peer_id, _) in peers {
+		for peer_id in peers {
 			if sealed.is_empty() {
 				let rlp =  ChainSync::create_latest_block_rlp(io.chain());
-				self.send_packet(io, peer_id, NEW_BLOCK_PACKET, rlp);
+				self.send_packet(io, *peer_id, NEW_BLOCK_PACKET, rlp);
 			} else {
 				for h in sealed {
 					let rlp =  ChainSync::create_new_block_rlp(io.chain(), h);
-					self.send_packet(io, peer_id, NEW_BLOCK_PACKET, rlp);
+					self.send_packet(io, *peer_id, NEW_BLOCK_PACKET, rlp);
 				}
 			}
-			self.peers.get_mut(&peer_id).unwrap().latest_hash = chain_info.best_block_hash.clone();
-			self.peers.get_mut(&peer_id).unwrap().latest_number = Some(chain_info.best_block_number);
+			if let Some(ref mut peer) = self.peers.get_mut(&peer_id) {
+				peer.latest_hash = chain_info.best_block_hash.clone();
+			}
 			sent += 1;
 		}
 		sent
 	}

 	/// propagates new known hashes to all peers
-	fn propagate_new_hashes(&mut self, chain_info: &BlockChainInfo, io: &mut SyncIo, peers: &[(PeerId, BlockNumber)]) -> usize {
+	fn propagate_new_hashes(&mut self, chain_info: &BlockChainInfo, io: &mut SyncIo, peers: &[PeerId]) -> usize {
 		trace!(target: "sync", "Sending NewHashes to {:?}", peers);
 		let mut sent = 0;
-		let last_parent = HeaderView::new(&io.chain().block_header(BlockID::Hash(chain_info.best_block_hash.clone())).unwrap()).parent_hash();
-		for &(peer_id, peer_number) in peers {
-			let peer_best = if chain_info.best_block_number - peer_number > MAX_PEER_LAG_PROPAGATION as BlockNumber {
-				// If we think peer is too far behind just send one latest hash
-				last_parent.clone()
-			} else {
-				self.peers.get(&peer_id).unwrap().latest_hash.clone()
-			};
-			sent += match ChainSync::create_new_hashes_rlp(io.chain(), &peer_best, &chain_info.best_block_hash) {
+		let last_parent = HeaderView::new(&io.chain().block_header(BlockID::Hash(chain_info.best_block_hash.clone()))
+			.expect("Best block always exists")).parent_hash();
+		for peer_id in peers {
+			sent += match ChainSync::create_new_hashes_rlp(io.chain(), &last_parent, &chain_info.best_block_hash) {
 				Some(rlp) => {
 					{
-						let peer = self.peers.get_mut(&peer_id).unwrap();
-						peer.latest_hash = chain_info.best_block_hash.clone();
-						peer.latest_number = Some(chain_info.best_block_number);
+						if let Some(ref mut peer) = self.peers.get_mut(&peer_id) {
+							peer.latest_hash = chain_info.best_block_hash.clone();
+						}
 					}
-					self.send_packet(io, peer_id, NEW_BLOCK_HASHES_PACKET, rlp);
+					self.send_packet(io, *peer_id, NEW_BLOCK_HASHES_PACKET, rlp);
 					1
 				},
 				None => 0
@@ -1717,7 +1744,6 @@ mod tests {
 				genesis: H256::zero(),
 				network_id: U256::zero(),
 				latest_hash: peer_latest_hash,
-				latest_number: None,
 				difficulty: None,
 				asking: PeerAsking::Nothing,
 				asking_blocks: Vec::new(),
--- a/sync/src/sync_io.rs
+++ b/sync/src/sync_io.rs
@@ -14,8 +14,11 @@
 // You should have received a copy of the GNU General Public License
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.

+use std::collections::HashMap;
+use ethcore::header::BlockNumber;
 use network::{NetworkContext, PeerId, PacketId, NetworkError};
 use ethcore::client::BlockChainClient;
+use util::{RwLock, Bytes};

 /// IO interface for the syning handler.
 /// Provides peer connection management and an interface to the blockchain client.
@@ -41,20 +44,24 @@ pub trait SyncIo {
 	}
 	/// Check if the session is expired
 	fn is_expired(&self) -> bool;
+	/// Return sync overlay
+	fn chain_overlay(&self) -> &RwLock<HashMap<BlockNumber, Bytes>>;
 }

 /// Wraps `NetworkContext` and the blockchain client
 pub struct NetSyncIo<'s, 'h> where 'h: 's {
 	network: &'s NetworkContext<'h>,
-	chain: &'s BlockChainClient
+	chain: &'s BlockChainClient,
+	chain_overlay: &'s RwLock<HashMap<BlockNumber, Bytes>>,
 }

 impl<'s, 'h> NetSyncIo<'s, 'h> {
 	/// Creates a new instance from the `NetworkContext` and the blockchain client reference.
-	pub fn new(network: &'s NetworkContext<'h>, chain: &'s BlockChainClient) -> NetSyncIo<'s, 'h> {
+	pub fn new(network: &'s NetworkContext<'h>, chain: &'s BlockChainClient, chain_overlay: &'s RwLock<HashMap<BlockNumber, Bytes>>) -> NetSyncIo<'s, 'h> {
 		NetSyncIo {
 			network: network,
 			chain: chain,
+			chain_overlay: chain_overlay,
 		}
 	}
 }
@@ -80,6 +87,10 @@ impl<'s, 'h> SyncIo for NetSyncIo<'s, 'h> {
 		self.chain
 	}

+	fn chain_overlay(&self) -> &RwLock<HashMap<BlockNumber, Bytes>> {
+		self.chain_overlay
+	}
+
 	fn peer_info(&self, peer_id: PeerId) -> String {
 		self.network.peer_info(peer_id)
 	}
--- a/sync/src/tests/chain.rs
+++ b/sync/src/tests/chain.rs
@@ -95,6 +95,27 @@ fn forked() {
 	assert_eq!(&*net.peer(2).chain.numbers.read(), &peer1_chain);
 }

+#[test]
+fn forked_with_misbehaving_peer() {
+	::env_logger::init().ok();
+	let mut net = TestNet::new(3);
+	// peer 0 is on a totally different chain with higher total difficulty
+	net.peer_mut(0).chain = TestBlockChainClient::new_with_extra_data(b"fork".to_vec());
+	net.peer_mut(0).chain.add_blocks(500, EachBlockWith::Nothing);
+	net.peer_mut(1).chain.add_blocks(100, EachBlockWith::Nothing);
+	net.peer_mut(2).chain.add_blocks(100, EachBlockWith::Nothing);
+
+	net.peer_mut(1).chain.add_blocks(100, EachBlockWith::Nothing);
+	net.peer_mut(2).chain.add_blocks(200, EachBlockWith::Uncle);
+	// peer 1 should sync to peer 2, others should not change
+	let peer0_chain = net.peer(0).chain.numbers.read().clone();
+	let peer2_chain = net.peer(2).chain.numbers.read().clone();
+	net.sync();
+	assert_eq!(&*net.peer(0).chain.numbers.read(), &peer0_chain);
+	assert_eq!(&*net.peer(1).chain.numbers.read(), &peer2_chain);
+	assert_eq!(&*net.peer(2).chain.numbers.read(), &peer2_chain);
+}
+
 #[test]
 fn net_hard_fork() {
 	::env_logger::init().ok();
@@ -116,11 +137,12 @@ fn net_hard_fork() {

 #[test]
 fn restart() {
+	::env_logger::init().ok();
 	let mut net = TestNet::new(3);
 	net.peer_mut(1).chain.add_blocks(1000, EachBlockWith::Uncle);
 	net.peer_mut(2).chain.add_blocks(1000, EachBlockWith::Uncle);

-	net.sync_steps(8);
+	net.sync();

 	// make sure that sync has actually happened
 	assert!(net.peer(0).chain.chain_info().best_block_number > 100);
--- a/sync/src/tests/helpers.rs
+++ b/sync/src/tests/helpers.rs
@@ -26,6 +26,8 @@ pub struct TestIo<'p> {
 	pub chain: &'p mut TestBlockChainClient,
 	pub queue: &'p mut VecDeque<TestPacket>,
 	pub sender: Option<PeerId>,
+	pub to_disconnect: HashSet<PeerId>,
+	overlay: RwLock<HashMap<BlockNumber, Bytes>>,
 }

 impl<'p> TestIo<'p> {
@@ -33,16 +35,20 @@ impl<'p> TestIo<'p> {
 		TestIo {
 			chain: chain,
 			queue: queue,
-			sender: sender
+			sender: sender,
+			to_disconnect: HashSet::new(),
+			overlay: RwLock::new(HashMap::new()),
 		}
 	}
 }

 impl<'p> SyncIo for TestIo<'p> {
-	fn disable_peer(&mut self, _peer_id: PeerId) {
+	fn disable_peer(&mut self, peer_id: PeerId) {
+		self.disconnect_peer(peer_id);
 	}

-	fn disconnect_peer(&mut self, _peer_id: PeerId) {
+	fn disconnect_peer(&mut self, peer_id: PeerId) {
+		self.to_disconnect.insert(peer_id);
 	}

 	fn is_expired(&self) -> bool {
@@ -70,6 +76,10 @@ impl<'p> SyncIo for TestIo<'p> {
 	fn chain(&self) -> &BlockChainClient {
 		self.chain
 	}
+
+	fn chain_overlay(&self) -> &RwLock<HashMap<BlockNumber, Bytes>> {
+		&self.overlay
+	}
 }

 pub struct TestPacket {
@@ -135,13 +145,30 @@ impl TestNet {
 	pub fn sync_step(&mut self) {
 		for peer in 0..self.peers.len() {
 			if let Some(packet) = self.peers[peer].queue.pop_front() {
-				let mut p = self.peers.get_mut(packet.recipient).unwrap();
-				trace!("--- {} -> {} ---", peer, packet.recipient);
-				ChainSync::dispatch_packet(&p.sync, &mut TestIo::new(&mut p.chain, &mut p.queue, Some(peer as PeerId)), peer as PeerId, packet.packet_id, &packet.data);
-				trace!("----------------");
+				let disconnecting = {
+					let mut p = self.peers.get_mut(packet.recipient).unwrap();
+					trace!("--- {} -> {} ---", peer, packet.recipient);
+					let to_disconnect = {
+						let mut io = TestIo::new(&mut p.chain, &mut p.queue, Some(peer as PeerId));
+						ChainSync::dispatch_packet(&p.sync, &mut io, peer as PeerId, packet.packet_id, &packet.data);
+						io.to_disconnect
+					};
+					for d in &to_disconnect {
+						// notify this that disconnecting peers are disconnecting
+						let mut io = TestIo::new(&mut p.chain, &mut p.queue, Some(*d));
+						p.sync.write().on_peer_aborting(&mut io, *d);
+					}
+					to_disconnect
+				};
+				for d in &disconnecting {
+					// notify other peers that this peer is disconnecting
+					let mut p = self.peers.get_mut(*d).unwrap();
+					let mut io = TestIo::new(&mut p.chain, &mut p.queue, Some(peer as PeerId));
+					p.sync.write().on_peer_aborting(&mut io, peer as PeerId);
+				}
 			}
-			let mut p = self.peers.get_mut(peer).unwrap();
-			p.sync.write().maintain_sync(&mut TestIo::new(&mut p.chain, &mut p.queue, None));
+
+			self.sync_step_peer(peer);
 		}
 	}

--- a/util/Cargo.toml
+++ b/util/Cargo.toml
@@ -3,7 +3,7 @@ description = "Ethcore utility library"
 homepage = "http://ethcore.io"
 license = "GPL-3.0"
 name = "ethcore-util"
-version = "1.3.1"
+version = "1.3.6"
 authors = ["Ethcore <admin@ethcore.io>"]
 build = "build.rs"

--- a/util/io/src/lib.rs
+++ b/util/io/src/lib.rs
@@ -68,6 +68,8 @@ mod panics;
 use mio::{EventLoop, Token};
 use std::fmt;

+pub use worker::LOCAL_STACK_SIZE;
+
 #[derive(Debug)]
 /// IO Error
 pub enum IoError {
--- a/util/io/src/worker.rs
+++ b/util/io/src/worker.rs
@@ -22,9 +22,19 @@ use crossbeam::sync::chase_lev;
 use service::{HandlerId, IoChannel, IoContext};
 use IoHandler;
 use panics::*;
+use std::cell::Cell;

 use std::sync::{Condvar as SCondvar, Mutex as SMutex};

+const STACK_SIZE: usize = 16*1024*1024;
+
+thread_local! {
+	/// Stack size
+	/// Should be modified if it is changed in Rust since it is no way
+	/// to know or get it
+	pub static LOCAL_STACK_SIZE: Cell<usize> = Cell::new(::std::env::var("RUST_MIN_STACK").ok().and_then(|s| s.parse().ok()).unwrap_or(2 * 1024 * 1024));
+}
+
 pub enum WorkType<Message> {
 	Readable,
 	Writable,
@@ -66,8 +76,9 @@ impl Worker {
 			deleting: deleting.clone(),
 			wait_mutex: wait_mutex.clone(),
 		};
-		worker.thread = Some(thread::Builder::new().name(format!("IO Worker #{}", index)).spawn(
+		worker.thread = Some(thread::Builder::new().stack_size(STACK_SIZE).name(format!("IO Worker #{}", index)).spawn(
 			move || {
+				LOCAL_STACK_SIZE.with(|val| val.set(STACK_SIZE));
 				panic_handler.catch_panic(move || {
 					Worker::work_loop(stealer, channel.clone(), wait, wait_mutex.clone(), deleting)
 				}).unwrap()
--- a/util/network/src/connection.rs
+++ b/util/network/src/connection.rs
@@ -110,8 +110,8 @@ impl<Socket: GenericSocket> GenericConnection<Socket> {
 		}
 		if !self.interest.is_writable() {
 			self.interest.insert(EventSet::writable());
-			io.update_registration(self.token).ok();
 		}
+		io.update_registration(self.token).ok();
 	}

 	/// Check if this connection has data to be sent.
--- a/util/network/src/host.rs
+++ b/util/network/src/host.rs
@@ -580,7 +580,8 @@ impl Host {
 	}

 	fn handshake_count(&self) -> usize {
-		self.sessions.read().count() - self.session_count()
+		// session_count < total_count is possible because of the data race.
+		self.sessions.read().count().saturating_sub(self.session_count())
 	}

 	fn keep_alive(&self, io: &IoContext<NetworkIoMessage>) {
--- a/util/src/hash.rs
+++ b/util/src/hash.rs
@@ -77,11 +77,11 @@ pub fn clean_0x(s: &str) -> &str {

 macro_rules! impl_hash {
 	($from: ident, $size: expr) => {
-		#[derive(Eq)]
 		#[repr(C)]
 		/// Unformatted binary data of fixed length.
 		pub struct $from (pub [u8; $size]);

+
 		impl From<[u8; $size]> for $from {
 			fn from(bytes: [u8; $size]) -> Self {
 				$from(bytes)
@@ -263,6 +263,8 @@ macro_rules! impl_hash {
 			}
 		}

+		impl Eq for $from {}
+
 		impl PartialEq for $from {
 			fn eq(&self, other: &Self) -> bool {
 				for i in 0..$size {
--- a/util/src/migration/mod.rs
+++ b/util/src/migration/mod.rs
@@ -102,6 +102,12 @@ impl From<::std::io::Error> for Error {
 	}
 }

+impl From<String> for Error {
+	fn from(e: String) -> Self {
+		Error::Custom(e)
+	}
+}
+
 /// A generalized migration from the given db to a destination db.
 pub trait Migration: 'static {
 	/// Number of columns in database after the migration.
--- a/util/src/misc.rs
+++ b/util/src/misc.rs
@@ -24,7 +24,7 @@ use target_info::Target;
 include!(concat!(env!("OUT_DIR"), "/version.rs"));
 include!(concat!(env!("OUT_DIR"), "/rustc_version.rs"));

-#[derive(PartialEq,Eq,Clone,Copy)]
+#[derive(PartialEq, Eq, Clone, Copy, Debug)]
 /// Boolean type for clean/dirty status.
 pub enum Filth {
 	/// Data has not been changed.
--- a/util/src/rlp/bytes.rs
+++ b/util/src/rlp/bytes.rs
@@ -174,6 +174,8 @@ pub enum FromBytesError {
 	DataIsTooLong,
 	/// Integer-representation is non-canonically prefixed with zero byte(s).
 	ZeroPrefixedInt,
+	/// String representation is not utf-8
+	InvalidUtf8,
 }

 impl StdError for FromBytesError {
@@ -199,7 +201,7 @@ pub trait FromBytes: Sized {

 impl FromBytes for String {
 	fn from_bytes(bytes: &[u8]) -> FromBytesResult<String> {
-		Ok(::std::str::from_utf8(bytes).unwrap().to_owned())
+		::std::str::from_utf8(bytes).map(|s| s.to_owned()).map_err(|_| FromBytesError::InvalidUtf8)
 	}
 }

--- a/util/src/standard.rs
+++ b/util/src/standard.rs
@@ -46,4 +46,4 @@ pub use rustc_serialize::hex::{FromHex, FromHexError};
 pub use heapsize::HeapSizeOf;
 pub use itertools::Itertools;

-pub use parking_lot::{Condvar, Mutex, MutexGuard, RwLock, RwLockReadGuard, RwLockWriteGuard};
+pub use parking_lot::{Condvar, Mutex, MutexGuard, RwLock, RwLockReadGuard, RwLockWriteGuard};
Author	SHA1	Message	Date
Arkadiy Paronyan	8492e3e61d	Backports to beta v1.3.6 (#2571 ) * v1.3.6 * Print backtrace on panic (#2535) * Don't activate peers on connect; Test (#2537) * Removing unwarps from sync module (#2551) * Remove unwrap from client module (#2554) * remove unwraps in client * imporve block hash expect message * mining perf trace * Fixed race condition in trace import (#2555)	2016-10-11 15:53:45 +02:00
Denis S. Soldatov aka General-Beck	4b7c97783b	Update gitlab-ci remove javascript tag	2016-10-08 10:51:42 +07:00
Arkadiy Paronyan	6d14c5458b	Use global state cache when mining (#2529 )	2016-10-08 02:00:06 +02:00
arkpar	9239a7cd9e	v1.3.5	2016-10-08 01:02:41 +02:00
Arkadiy Paronyan	d27ecb6527	Transaction queue limited by gas (#2528 )	2016-10-08 00:59:04 +02:00
Robert Habermeier	5502340dea	Merge pull request #2521 from ethcore/update-appveyor-rustc-beta Update appveyor rustc [beta]	2016-10-07 17:39:41 +02:00
Denis S. Soldatov aka General-Beck	2313f9b4f1	Update gitlab-ci add javascript test	2016-10-07 22:31:09 +07:00
Robert Habermeier	324a5873d7	turn off MIR for windows builds	2016-10-07 16:07:01 +02:00
Robert Habermeier	b45e7f1c41	update rustc for appveyor to 1.12.0	2016-10-07 16:06:39 +02:00
Tomasz Drwięga	64af073bd4	Increase size of transaction queue by default (#2519 ) Conflicts: ethcore/src/miner/miner.rs parity/cli/config.full.toml parity/cli/mod.rs parity/configuration.rs	2016-10-07 14:11:33 +01:00
Arkadiy Paronyan	fe83046198	Backport to beta (#2518 ) * Handle reorganizations in the state cache * Renamed and documented a few methods * Basic test * Renamed pending to buffered * Caching optimizations * Fixed a test * Fixed a test	2016-10-07 14:09:52 +01:00
Tomasz Drwięga	8031910892	[beta] Fixing RPC Filter conversion to EthFilter (#2501 ) * Fixing RPC Filter conversion to EthFilter Conflicts: rpc/src/v1/impls/eth.rs rpc/src/v1/types/filter.rs * Removing limit * Fixing rpc tests	2016-10-07 12:16:09 +01:00
Tomasz Drwięga	73a3dac38c	[beta] Using pending block only if is not old (#2515 ) * Using pending block only if not old Conflicts: ethcore/src/miner/miner.rs rpc/src/v1/impls/eth.rs rpc/src/v1/impls/eth_filter.rs * Fixing compilation issues	2016-10-07 11:46:17 +01:00
Arkadiy Paronyan	bbaf5ed4f5	Backports into beta (#2512 ) * RocksDB version bump * Preserve cache on reverting the snapshot (#2488) * Preserve cache on reverting the snapshot * Renamed merge_with into replace_with * Renamed and documented snapshotting methods * Track dirty accounts in the state (#2461) * State to track dirty accounts * Removed clone_for_snapshot * Renaming stuff * Documentation and other minor fixes * Replaced MaybeAccount with Option * Adjustable stack size for EVM (#2483) * stack size for io workers & evm threshold * rust way to remember stack size * right value * 24kb size * some stack reduction * Fixed overflow panic in handshake_panic (#2495)	2016-10-07 10:49:48 +01:00
Tomasz Drwięga	9cf777510f	CLI to specify queue ordering strategy (#2494 ) * Alter gas priorities to include gas_price also * CLI options and tests * Adding ordering by gas * whitespace [ci:skip]	2016-10-07 09:04:13 +02:00
Nikolay Volf	9b398421ce	Run inplace upgrades after version update (#2411 ) * Update migration.rs In highly unlikely scenario when the bloom update fails it will at least try again on the next run * proper exchange	2016-10-07 09:03:49 +02:00
Tomasz Drwięga	a618dcaaf0	Fixing penalization in future (#2493 )	2016-10-06 15:52:09 +01:00
Nikolay Volf	50021c7611	Fix ethstore opening all key files in the directory at once (BETA) (#2472 ) * get rid of collects & zips * not an option here!	2016-10-05 15:41:48 +02:00
Denis S. Soldatov aka General-Beck	f62d2e6ea8	Update gitlab-ci fix windows	2016-10-05 10:54:01 +07:00
Denis S. Soldatov aka General-Beck	7da8e7926d	Update gitlab-ci set RUSTFLAGS=-Zorbit=off windows	2016-10-05 08:38:33 +07:00
Denis S. Soldatov aka General-Beck	5363e75f3a	Update gitlab-ci add RUSTFLAGS=-Zorbit=false in windows build	2016-10-05 08:04:56 +07:00
Arkadiy Paronyan	31d667a29a	Merge pull request #2465 from ethcore/beta-staging Beta backports	2016-10-05 00:24:13 +02:00
arkpar	ca2bc92dda	Fixing tests	2016-10-04 23:24:16 +02:00
Marek Kotewicz	a0b71a9f52	fixed #2263 , geth keys with ciphertext shorter than 32 bytes (#2318 ) * fixed #2263, geth keys with ciphertext shorter than 32 bytes * replace unwrap with more helpful expect * tests for decrypting short secrets	2016-10-04 22:08:31 +02:00
arkpar	300c0c120b	v1.3.4	2016-10-04 22:00:59 +02:00
Nikolay Volf	b228dc7b54	IPC-library dependency fork & bump for beta (#2455 ) * bump json-ipc-server * bump again	2016-10-04 18:18:07 +02:00
Denis S. Soldatov aka General-Beck	df4d98001a	update gitlab-ci set RUST 1.11 for windows	2016-10-04 14:43:49 +08:00
Robert Habermeier	2e4672ea13	Merge pull request #2414 from ethcore/compilation-beta fix broken beta compilation (backport to beta)	2016-10-02 21:07:35 +02:00
Arkadiy Paronyan	7f7fe33bde	Jumptable cache (#2435 ) * v1.3.3 * Jumptable cache	2016-10-02 19:52:53 +02:00
Arkadiy Paronyan	3d313d592a	Disabling debug symbols due to rustc 1.12 memory usage regression	2016-10-02 09:45:27 +02:00
NikVolf	abc6970d08	fix ethkey more	2016-10-01 15:29:11 +03:00
NikVolf	fa636d402d	ethkey eq	2016-10-01 13:04:08 +03:00
NikVolf	73d6666294	some checksums	2016-10-01 00:28:31 +03:00
Denis S. Soldatov aka General-Beck	f16ccacd22	Update gitlab-ci add checksum	2016-09-30 21:03:05 +07:00
Nikolay Volf	ba3de5d3b9	rayon bump	2016-09-30 02:25:35 +03:00
Robert Habermeier	f16de5501a	fix broken beta compilation	2016-09-29 23:03:02 +03:00
Arkadiy Paronyan	e298ab30e4	Quick fix for missing tree route blocks (#2400 )	2016-09-29 14:47:13 +02:00
Tomasz Drwięga	63d3a4dd59	Beta Backports (#2396 ) * Removing extras data from retracted blocks. (#2375) * Removing extras data from retracted blocks. * Adding a test case Conflicts: ethcore/src/blockchain/blockchain.rs * Fixing transaction queue Conflicts: ethcore/src/miner/transaction_queue.rs * Prioritizing re-imported transactions (#2372) * Prioritizing re-imported transactions * Fixing compilation on beta Conflicts: Cargo.lock ethcore/src/client/client.rs ethcore/src/miner/transaction_queue.rs * Post-merge fixes	2016-09-29 13:19:53 +02:00
Arkadiy Paronyan	0e55b6c6c9	Cache the fork block header after snapshot restoration (#2391 )	2016-09-29 12:34:40 +02:00
Nikolay Volf	4d115987cb	Accounts bloom (#2357 ) * proper bloom * incremental bloom updates * crate update * return of the column * fix n^2 byteorder write * add notes to funs * working bloom commits * Optimizations * bloom diag * migration basic * migration ongoing * migration finalizing * mingration api workarounds * fix test_client setups * snapshot bloom update * review fixes * just forward keys in the migration * migration extra tracing * fix migration path * remove close pray * review issues	2016-09-29 11:27:41 +02:00
Tomasz Drwięga	2d623f14db	Disable colors for signer token in beta (#2379 )	2016-09-28 23:33:50 +02:00
Robert Habermeier	1d1a3b9d02	correct sync memory usage calculation (#2386 )	2016-09-28 23:00:27 +02:00
Arkadiy Paronyan	1d69b0e124	Fixing jit feature compilation (#2376 ) * Fixing jit feature compilation * Fixing jit feature compilation (#2310) Conflicts: Cargo.lock * Delegatecall support	2016-09-28 17:25:32 +02:00
Arkadiy Paronyan	3c59475be6	Clear state cache on sealed block import (#2377 )	2016-09-28 17:24:47 +02:00
Denis S. Soldatov aka General-Beck	facab31551	Update gitlab-ci add RUST_BACKTRACE=1 in test stage	2016-09-28 01:52:17 +07:00
Arkadiy Paronyan	c9cfcd2728	Canonical state cache (#2308 ) * State cache * Reduced copying data between caches Whitespace and optional symbols * Set a limit on storage cache * Style and docs	2016-09-27 16:44:32 +02:00
Arkadiy Paronyan	557dbb73b8	DIV optimization (#2353 )	2016-09-27 14:04:08 +02:00
Gav Wood	6f772a28e2	Reorder transaction_by_hash to favour canon search (#2331 ) * Reorder transaction_by_hash to favour canon search * Fix test.	2016-09-27 12:16:42 +02:00
Tomasz Drwięga	16f3119547	Lenient bytes deserialization (#2340 ) * Lenient bytes deserialization * Error when deserializing invalid hex * Error when deserializing invalid hex Conflicts: rpc/src/v1/types/bytes.rs	2016-09-27 11:24:27 +02:00
Tomasz Drwięga	c3741640f7	Penalize transactions with gas above gas limit (#2271 ) * Handle RLP to string UTF-8 decoding errors (#2217) * Penalize transactions with gas above gas limit * Avoid penalizing legit transactions * saturating not overflowing * Remove crufty code * Introduce gas price ordering. * Gas before gas-price, as long as the minimum price is met. * saturating add	2016-09-25 12:14:39 +02:00
Denis S. Soldatov aka General-Beck	decca7f698	Update gitlab-ci deploy fix	2016-09-24 05:01:48 +07:00
Denis S. Soldatov aka General-Beck	fc53726c7f	Update gitlab-ci fix armv7 path	2016-09-24 03:00:22 +07:00
Denis S. Soldatov aka General-Beck	e2b81bc08d	Update gitlab-ci [ci skip] rename x86_64-unknown-centos-gnu	2016-09-24 00:11:23 +07:00
Denis S. Soldatov aka General-Beck	4d2d1eac1f	Update gitlab-ci fix path in arm	2016-09-23 23:45:57 +07:00
Denis S. Soldatov aka General-Beck	5572e3dd1d	Update gitlab-ci fix windows deploy to S3 add ubuntu 14.04 build	2016-09-23 23:40:25 +07:00
Tomasz Drwięga	0db1c0d336	Peek transaction queue via RPC (#2270 ) * Handle RLP to string UTF-8 decoding errors (#2217) * pending transactions	2016-09-23 18:13:03 +02:00
Denis S. Soldatov aka General-Beck	905f04dc9d	Update Ubuntu arm Dockerfile [ci skip] remove CC and CXX env backport to beta https://github.com/ethcore/parity/pull/2064	2016-09-23 21:35:04 +07:00
Denis S. Soldatov aka General-Beck	f560cf360c	Update Dockerfile ubuntu-aarch64 [ci skip] remove CC and CXX env backport to beta https://github.com/ethcore/parity/pull/2064	2016-09-23 21:34:16 +07:00
Tomasz Drwięga	f5d48cbf2a	Handle RLP to string UTF-8 decoding errors (#2217 ) (#2226 )	2016-09-22 14:48:54 +02:00
Denis S. Soldatov aka General-Beck	d59e2ecbc6	Update gitlab-ci fix x86_64-pc-windows-msvc	2016-09-21 22:36:54 +07:00
Denis S. Soldatov aka General-Beck	a97ca5aaf4	Update gitlab-ci remove -export	2016-09-21 22:25:51 +07:00
Tomasz Drwięga	df61b1b328	Fixing compilation without ui feature (#2207 )	2016-09-21 11:51:49 +01:00
Tomasz Drwięga	52a69d19e6	Avoid cloning clean stuff (#2173 )	2016-09-20 23:10:26 +08:00
Arkadiy Paronyan	33084aaa07	v1.3.2 (#2200 )	2016-09-20 14:21:17 +08:00