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
Backport to beta (#2518 )
2016-10-07 14:11:33 +01:00 · 2016-10-07 14:09:52 +01:00 · 2016-10-07 12:16:09 +01:00 · 2016-10-07 11:46:17 +01:00 · 2016-10-07 10:49:48 +01:00 · 2016-10-07 09:04:13 +02:00
41 changed files with 1263 additions and 518 deletions
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -264,9 +264,10 @@ 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
-    - rustup default 1.11.0-x86_64-pc-windows-msvc
+    - set RUSTFLAGS=-Zorbit=off
+    - rustup default stable-x86_64-pc-windows-msvc
    - cargo build --release --verbose
-    - md5sum target\release\parity >> checksum
+    - 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
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,12 +1,12 @@
 [root]
 name = "parity"
-version = "1.3.3"
+version = "1.3.4"
 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 1.3.3",
+ "ethcore-util 1.3.4",
 "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)",
 ]
@@ -192,7 +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)",
@@ -208,12 +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]]
@@ -236,7 +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)",
@@ -269,7 +270,7 @@ dependencies = [
 "ethcore-ipc 1.3.0",
 "ethcore-ipc-codegen 1.3.0",
 "ethcore-ipc-nano 1.3.0",
- "ethcore-util 1.3.3",
+ "ethcore-util 1.3.4",
 "ethjson 0.1.0",
 "ethstore 0.1.0",
 "evmjit 1.3.0",
@@ -293,7 +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 1.3.3",
+ "ethcore-util 1.3.4",
 "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)",
@@ -335,7 +336,7 @@ name = "ethcore-ipc"
 version = "1.3.0"
 dependencies = [
 "ethcore-devtools 1.3.0",
- "ethcore-util 1.3.3",
+ "ethcore-util 1.3.4",
 "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)",
 ]
@@ -380,7 +381,7 @@ dependencies = [
 "ethcore-ipc 1.3.0",
 "ethcore-ipc-codegen 1.3.0",
 "ethcore-ipc-nano 1.3.0",
- "ethcore-util 1.3.3",
+ "ethcore-util 1.3.4",
 "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)",
@@ -392,7 +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 1.3.3",
+ "ethcore-util 1.3.4",
 "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)",
@@ -407,7 +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 1.3.3",
+ "ethcore-util 1.3.4",
 "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)",
@@ -431,10 +432,10 @@ dependencies = [
 "ethcore-devtools 1.3.0",
 "ethcore-io 1.3.0",
 "ethcore-ipc 1.3.0",
- "ethcore-util 1.3.3",
+ "ethcore-util 1.3.4",
 "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)",
@@ -454,7 +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 1.3.3",
+ "ethcore-util 1.3.4",
 "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)",
@@ -465,7 +466,7 @@ dependencies = [

 [[package]]
 name = "ethcore-util"
-version = "1.3.3"
+version = "1.3.4"
 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)",
@@ -498,7 +499,7 @@ dependencies = [
 name = "ethjson"
 version = "0.1.0"
 dependencies = [
- "ethcore-util 1.3.3",
+ "ethcore-util 1.3.4",
 "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)",
@@ -546,7 +547,7 @@ dependencies = [
 "ethcore-ipc-codegen 1.3.0",
 "ethcore-ipc-nano 1.3.0",
 "ethcore-network 1.3.0",
- "ethcore-util 1.3.3",
+ "ethcore-util 1.3.4",
 "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)",
@@ -571,8 +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"
@@ -706,7 +710,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "json-ipc-server"
 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 = [
 "bytes 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "env_logger 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -885,7 +889,7 @@ name = "nanomsg-sys"
 version = "0.5.0"
 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)",
 ]

@@ -1012,7 +1016,7 @@ dependencies = [

 [[package]]
 name = "number_prefix"
-version = "0.2.5"
+version = "0.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "num 0.1.32 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1221,7 +1225,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "rocksdb"
 version = "0.4.5"
-source = "git+https://github.com/ethcore/rust-rocksdb#485dd747a2c9a9f910fc8ac696fc9edf5fa22aa3"
+source = "git+https://github.com/ethcore/rust-rocksdb#ffc7c82380fe8569f85ae6743f7f620af2d4a679"
 dependencies = [
 "libc 0.2.12 (registry+https://github.com/rust-lang/crates.io-index)",
 "rocksdb-sys 0.3.0 (git+https://github.com/ethcore/rust-rocksdb)",
@@ -1230,9 +1234,9 @@ dependencies = [
 [[package]]
 name = "rocksdb-sys"
 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)",
 ]

@@ -1249,7 +1253,7 @@ dependencies = [

 [[package]]
 name = "rpassword"
-version = "0.2.2"
+version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1263,7 +1267,7 @@ name = "rust-crypto"
 version = "0.2.36"
 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)",
 "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)",
@@ -1331,7 +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]]
@@ -1375,7 +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]]
@@ -1386,6 +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"
@@ -1399,6 +1411,19 @@ dependencies = [
 "unicode-xid 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]

+[[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"
 version = "0.1.0"
@@ -1641,13 +1666,13 @@ dependencies = [
 "checksum cookie 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)" = "90266f45846f14a1e986c77d1e9c2626b8c342ed806fe60241ec38cc8697b245"
 "checksum crossbeam 0.2.9 (registry+https://github.com/rust-lang/crates.io-index)" = "fb974f835e90390c5f9dfac00f05b06dc117299f5ea4e85fbc7bb443af4911cc"
 "checksum ctrlc 1.1.1 (git+https://github.com/ethcore/rust-ctrlc.git)" = "<none>"
-"checksum daemonize 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "271ec51b7e0bee92f0d04601422c73eb76ececf197026711c97ad25038a010cf"
+"checksum daemonize 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "0239832c1b4ca406d5ec73728cf4c7336d25cf85dd32db9e047e9e706ee0e935"
 "checksum deque 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "1614659040e711785ed8ea24219140654da1729f3ec8a47a9719d041112fe7bf"
-"checksum docopt 0.6.80 (registry+https://github.com/rust-lang/crates.io-index)" = "4cc0acb4ce0828c6a5a11d47baa432fe885881c27428c3a4e473e454ffe57a76"
+"checksum docopt 0.6.86 (registry+https://github.com/rust-lang/crates.io-index)" = "4a7ef30445607f6fc8720f0a0a2c7442284b629cf0d049286860fae23e71c4d9"
 "checksum elastic-array 0.4.0 (git+https://github.com/ethcore/elastic-array)" = "<none>"
 "checksum env_logger 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "aba65b63ffcc17ffacd6cf5aa843da7c5a25e3bd4bbe0b7def8b214e411250e5"
 "checksum eth-secp256k1 0.5.4 (git+https://github.com/ethcore/rust-secp256k1)" = "<none>"
-"checksum gcc 0.3.28 (registry+https://github.com/rust-lang/crates.io-index)" = "3da3a2cbaeb01363c8e3704fd9fd0eb2ceb17c6f27abd4c1ef040fb57d20dc79"
+"checksum gcc 0.3.35 (registry+https://github.com/rust-lang/crates.io-index)" = "91ecd03771effb0c968fd6950b37e89476a578aaf1c70297d8e92b6516ec3312"
 "checksum glob 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "8be18de09a56b60ed0edf84bc9df007e30040691af7acd1c41874faac5895bfb"
 "checksum hamming 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "65043da274378d68241eb9a8f8f8aa54e349136f7b8e12f63e3ef44043cc30e1"
 "checksum heapsize 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "abb306abb8d398e053cfb1b3e7b72c2f580be048b85745c52652954f8ad1439c"
@@ -1660,7 +1685,7 @@ dependencies = [
 "checksum igd 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "c8c12b1795b8b168f577c45fa10379b3814dcb11b7ab702406001f0d63f40484"
 "checksum isatty 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "7408a548dc0e406b7912d9f84c261cc533c1866e047644a811c133c56041ac0c"
 "checksum itertools 0.4.13 (registry+https://github.com/rust-lang/crates.io-index)" = "086e1fa5fe48840b1cfdef3a20c7e3115599f8d5c4c87ef32a794a7cdd184d76"
-"checksum json-ipc-server 0.2.4 (git+https://github.com/ethcore/json-ipc-server.git)" = "<none>"
+"checksum json-ipc-server 0.2.4 (git+https://github.com/ethcore/json-ipc-server.git?branch=beta)" = "<none>"
 "checksum jsonrpc-core 2.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "ec4477e4e8218da23caa5dd31f4eb39999aa0ea9035660617eccfb19a23bf5ad"
 "checksum jsonrpc-http-server 6.1.0 (git+https://github.com/ethcore/jsonrpc-http-server.git)" = "<none>"
 "checksum kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7507624b29483431c0ba2d82aece8ca6cdba9382bff4ddd0f7490560c056098d"
@@ -1693,7 +1718,7 @@ dependencies = [
 "checksum num-rational 0.1.32 (registry+https://github.com/rust-lang/crates.io-index)" = "48cdcc9ff4ae2a8296805ac15af88b3d88ce62128ded0cb74ffb63a587502a84"
 "checksum num-traits 0.1.32 (registry+https://github.com/rust-lang/crates.io-index)" = "51eab148f171aefad295f8cece636fc488b9b392ef544da31ea4b8ef6b9e9c39"
 "checksum num_cpus 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "51fedae97a05f7353612fe017ab705a37e6db8f4d67c5c6fe739a9e70d6eed09"
-"checksum number_prefix 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)" = "084d05f4bf60621a9ac9bde941a410df548f4de9545f06e5ee9d3aef4b97cd77"
+"checksum number_prefix 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "b09f7c223751819881e1b95670d36fb12cdaa89848147f2222f1a2b691d5f0a3"
 "checksum odds 0.2.12 (registry+https://github.com/rust-lang/crates.io-index)" = "b28c06e81b0f789122d415d6394b5fe849bde8067469f4c2980d3cdc10c78ec1"
 "checksum parity-dapps 1.4.0 (git+https://github.com/ethcore/parity-ui.git)" = "<none>"
 "checksum parity-dapps-home 1.4.0 (git+https://github.com/ethcore/parity-ui.git)" = "<none>"
@@ -1721,7 +1746,7 @@ dependencies = [
 "checksum rocksdb 0.4.5 (git+https://github.com/ethcore/rust-rocksdb)" = "<none>"
 "checksum rocksdb-sys 0.3.0 (git+https://github.com/ethcore/rust-rocksdb)" = "<none>"
 "checksum rotor 0.6.3 (git+https://github.com/ethcore/rotor)" = "<none>"
-"checksum rpassword 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "5d3a99497c5c544e629cc8b359ae5ede321eba5fa8e5a8078f3ced727a976c3f"
+"checksum rpassword 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "320da1dfcf5c570a6c07ff60bb7cd4cdc986d2ea89caea139f2247371ab6a1df"
 "checksum rust-crypto 0.2.36 (registry+https://github.com/rust-lang/crates.io-index)" = "f76d05d3993fd5f4af9434e8e436db163a12a9d40e1a58a726f27a01dfd12a2a"
 "checksum rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)" = "6159e4e6e559c81bd706afe9c8fd68f547d3e851ce12e76b1de7914bab61691b"
 "checksum rustc_version 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "c5f5376ea5e30ce23c03eb77cbe4962b988deead10910c372b226388b594c084"
@@ -1738,9 +1763,11 @@ dependencies = [
 "checksum solicit 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)" = "172382bac9424588d7840732b250faeeef88942e37b6e35317dce98cafdd75b2"
 "checksum spmc 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "93bdab61c1a413e591c4d17388ffa859eaff2df27f1e13a5ec8b716700605adf"
 "checksum stable-heap 0.1.0 (git+https://github.com/carllerche/stable-heap?rev=3c5cd1ca47)" = "<none>"
-"checksum strsim 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e4d73a2c36a4d095ed1a6df5cbeac159863173447f7a82b3f4757426844ab825"
+"checksum strsim 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "50c069df92e4b01425a8bf3576d5d417943a6a7272fbabaf5bd80b1aaa76442e"
 "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 = "1.3.3"
+version = "1.3.4"
 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}

--- a/ethcore/src/account.rs
+++ b/ethcore/src/account.rs
@@ -16,7 +16,6 @@

 //! Single account in the system.

-use std::collections::hash_map::Entry;
 use util::*;
 use pod_account::*;
 use account_db::*;
@@ -24,9 +23,11 @@ use lru_cache::LruCache;

 use std::cell::{RefCell, Cell};

-const STORAGE_CACHE_ITEMS: usize = 4096;
+const STORAGE_CACHE_ITEMS: usize = 8192;

 /// Single account in the system.
+/// 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,
@@ -46,8 +47,6 @@ pub struct Account {
 	code_size: Option<u64>,
 	// Code cache of the account.
 	code_cache: Arc<Bytes>,
-	// Account is new or has been modified.
-	filth: Filth,
 	// Account code new or has been modified.
 	code_filth: Filth,
 	// Cached address hash.
@@ -67,7 +66,6 @@ impl Account {
 			code_hash: code.sha3(),
 			code_size: Some(code.len() as u64),
 			code_cache: Arc::new(code),
-			filth: Filth::Dirty,
 			code_filth: Filth::Dirty,
 			address_hash: Cell::new(None),
 		}
@@ -89,7 +87,6 @@ impl Account {
 			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)),
-			filth: Filth::Dirty,
 			address_hash: Cell::new(None),
 		}
 	}
@@ -105,7 +102,6 @@ impl Account {
 			code_hash: SHA3_EMPTY,
 			code_cache: Arc::new(vec![]),
 			code_size: Some(0),
-			filth: Filth::Dirty,
 			code_filth: Filth::Clean,
 			address_hash: Cell::new(None),
 		}
@@ -123,7 +119,6 @@ impl Account {
 			code_hash: r.val_at(3),
 			code_cache: Arc::new(vec![]),
 			code_size: None,
-			filth: Filth::Clean,
 			code_filth: Filth::Clean,
 			address_hash: Cell::new(None),
 		}
@@ -141,7 +136,6 @@ impl Account {
 			code_hash: SHA3_EMPTY,
 			code_cache: Arc::new(vec![]),
 			code_size: None,
-			filth: Filth::Dirty,
 			code_filth: Filth::Clean,
 			address_hash: Cell::new(None),
 		}
@@ -153,7 +147,6 @@ impl Account {
 		self.code_hash = code.sha3();
 		self.code_cache = Arc::new(code);
 		self.code_size = Some(self.code_cache.len() as u64);
-		self.filth = Filth::Dirty;
 		self.code_filth = Filth::Dirty;
 	}

@@ -164,17 +157,7 @@ impl Account {

 	/// 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_changes.entry(key) {
-			Entry::Occupied(ref mut entry) if entry.get() != &value => {
-				entry.insert(value);
-				self.filth = Filth::Dirty;
-			},
-			Entry::Vacant(entry) => {
-				entry.insert(value);
-				self.filth = Filth::Dirty;
-			},
-			_ => {},
-		}
+		self.storage_changes.insert(key, value);
 	}

 	/// Get (and cache) the contents of the trie's storage at `key`.
@@ -263,17 +246,6 @@ impl Account {
 		!self.code_cache.is_empty() || (self.code_cache.is_empty() && self.code_hash == SHA3_EMPTY)
 	}

-	/// Is this a new or modified account?
-	pub fn is_dirty(&self) -> bool {
-		self.filth == Filth::Dirty || self.code_filth == Filth::Dirty || !self.storage_is_clean()
-	}
-
-	/// Mark account as clean.
-	pub fn set_clean(&mut self) {
-		assert!(self.storage_is_clean());
-		self.filth = Filth::Clean
-	}
-
 	/// Provide a database to get `code_hash`. Should not be called if it is a contract without code.
 	pub fn cache_code(&mut self, db: &AccountDB) -> bool {
 		// TODO: fill out self.code_cache;
@@ -326,25 +298,18 @@ impl Account {
 	/// 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_changes` to the backing DB and update `storage_root`.
@@ -406,7 +371,6 @@ impl Account {
 			code_hash: self.code_hash.clone(),
 			code_size: self.code_size.clone(),
 			code_cache: self.code_cache.clone(),
-			filth: self.filth,
 			code_filth: self.code_filth,
 			address_hash: self.address_hash.clone(),
 		}
@@ -427,10 +391,10 @@ impl Account {
 		account
 	}

-	/// Replace self with the data from other account merging storage cache
-	pub fn merge_with(&mut self, other: Account) {
-		assert!(self.storage_is_clean());
-		assert!(other.storage_is_clean());
+	/// 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;
@@ -443,6 +407,7 @@ impl Account {
 		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;
 	}
 }

--- a/ethcore/src/client/client.rs
+++ b/ethcore/src/client/client.rs
@@ -303,9 +303,8 @@ impl Client {

 		// Enact Verified Block
 		let parent = chain_has_parent.unwrap();
-		let last_hashes = self.build_last_hashes(header.parent_hash.clone());
-		let is_canon = header.parent_hash == self.chain.best_block_hash();
-		let db = if is_canon { self.state_db.lock().boxed_clone_canon() } else { self.state_db.lock().boxed_clone() };
+		let last_hashes = self.build_last_hashes(header.parent_hash().clone());
+		let db = self.state_db.lock().boxed_clone_canon(&header.parent_hash);

 		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 {
@@ -442,7 +441,6 @@ 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.
@@ -458,6 +456,8 @@ 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();
@@ -532,9 +532,11 @@ 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.")
@@ -1036,7 +1038,7 @@ impl BlockChainClient for Client {
 	}

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

@@ -1085,9 +1087,9 @@ impl MiningBlockChainClient for Client {

 		let block_data = block.rlp_bytes();
 		// Clear canonical state cache
-		self.state_db.lock().clear_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
@@ -558,6 +558,6 @@ 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/evm/interpreter/shared_cache.rs
+++ b/ethcore/src/evm/interpreter/shared_cache.rs
@@ -21,7 +21,7 @@ use util::sha3::*;
 use bit_set::BitSet;
 use super::super::instructions;

-const CACHE_CODE_ITEMS: usize = 4096;
+const CACHE_CODE_ITEMS: usize = 65536;

 /// GLobal cache for EVM interpreter
 pub struct SharedCache {
--- 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.
@@ -212,8 +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);
@@ -265,7 +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 {
@@ -285,7 +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![]);

@@ -331,7 +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)
@@ -413,7 +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;
@@ -473,10 +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);
 			}
 		}
--- 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, options.tx_gas_limit
+		)));
 		Arc::new(Miner {
 			transaction_queue: txq,
 			next_allowed_reseal: Mutex::new(Instant::now()),
@@ -444,6 +450,21 @@ 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;
@@ -516,29 +537,35 @@ 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).map(|c| (*c).clone()))
+		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) {
@@ -683,50 +710,74 @@ 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())
@@ -747,15 +798,15 @@ 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());
@@ -763,9 +814,8 @@ impl MinerService for Miner {
 				let receipts = pending.receipts().iter().cloned();

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

 	fn last_nonce(&self, address: &Address) -> Option<U256> {
@@ -918,7 +968,7 @@ 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};
@@ -969,6 +1019,7 @@ 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,
@@ -995,20 +1046,48 @@ 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
@@ -1025,16 +1104,16 @@ 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
@@ -49,7 +49,7 @@
 //!			balance: U256::from(1_000_000),
 //!		};
 //!
-//!		let mut txq = TransactionQueue::new();
+//!		let mut txq = TransactionQueue::default();
 //!		txq.add(st2.clone(), &default_nonce, TransactionOrigin::External).unwrap();
 //!		txq.add(st1.clone(), &default_nonce, TransactionOrigin::External).unwrap();
 //!
@@ -134,9 +134,17 @@ struct TransactionOrder {
 	/// Gas Price of the transaction.
 	/// Low gas price = Low priority (processed later)
 	gas_price: U256,
-	/// Gas (limit) of the transaction.
+	/// Gas usage priority factor. Usage depends on strategy.
+	/// Represents the linear increment in required gas price for heavy transactions.
+	///
+	/// High gas limit + Low gas price = Low priority
+	/// High gas limit + High gas price = High priority
+	gas_factor: U256,
+	/// Gas (limit) of the transaction. Usage depends on strategy.
 	/// Low gas limit = High priority (processed earlier)
 	gas: U256,
+	/// Transaction ordering strategy
+	strategy: PrioritizationStrategy,
 	/// Hash to identify associated transaction
 	hash: H256,
 	/// Origin of the transaction
@@ -147,11 +155,15 @@ struct TransactionOrder {


 impl TransactionOrder {
-	fn for_transaction(tx: &VerifiedTransaction, base_nonce: U256) -> Self {
+
+	fn for_transaction(tx: &VerifiedTransaction, base_nonce: U256, min_gas_price: U256, strategy: PrioritizationStrategy) -> Self {
+		let factor = (tx.transaction.gas >> 15) * min_gas_price;
 		TransactionOrder {
 			nonce_height: tx.nonce() - base_nonce,
 			gas_price: tx.transaction.gas_price,
 			gas: tx.transaction.gas,
+			gas_factor: factor,
+			strategy: strategy,
 			hash: tx.hash(),
 			origin: tx.origin,
 			penalties: 0,
@@ -199,18 +211,28 @@ impl Ord for TransactionOrder {
 			return self.origin.cmp(&b.origin);
 		}

-		// Then compare gas usage
-		let a_gas = self.gas;
-		let b_gas = b.gas;
-		if a_gas != b_gas {
-			return a_gas.cmp(&b_gas);
+		match self.strategy {
+			PrioritizationStrategy::GasAndGasPrice => {
+				if self.gas != b.gas {
+					return self.gas.cmp(&b.gas);
+				}
+			},
+			PrioritizationStrategy::GasFactorAndGasPrice => {
+				// avoiding overflows
+				// (gp1 - g1) > (gp2 - g2) <=>
+				// (gp1 + g2) > (gp2 + g1)
+				let f_a = self.gas_price + b.gas_factor;
+				let f_b = b.gas_price + self.gas_factor;
+				if f_a != f_b {
+					return f_b.cmp(&f_a);
+				}
+			},
+			PrioritizationStrategy::GasPriceOnly => {},
 		}

 		// Then compare gas_prices
-		let a_gas_price = self.gas_price;
-		let b_gas_price = b.gas_price;
-		if a_gas_price != b_gas_price {
-			return b_gas_price.cmp(&a_gas_price);
+		if self.gas_price != b.gas_price {
+			return b.gas_price.cmp(&self.gas_price);
 		}

 		// Compare hashes
@@ -350,8 +372,32 @@ pub struct AccountDetails {
 /// Transactions with `gas > (gas_limit + gas_limit * Factor(in percents))` are not imported to the queue.
 const GAS_LIMIT_HYSTERESIS: usize = 10; // (100/GAS_LIMIT_HYSTERESIS) %

+/// Describes the strategy used to prioritize transactions in the queue.
+#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+pub enum PrioritizationStrategy {
+	/// Use only gas price. Disregards the actual computation cost of the transaction.
+	/// i.e. Higher gas price = Higher priority
+	GasPriceOnly,
+	/// Use gas limit and then gas price.
+	/// i.e. Higher gas limit = Lower priority
+	GasAndGasPrice,
+	/// Calculate and use priority based on gas and gas price.
+	/// PRIORITY = GAS_PRICE - GAS/2^15 * MIN_GAS_PRICE
+	///
+	/// Rationale:
+	/// Heavy transactions are paying linear cost (GAS * GAS_PRICE)
+	/// while the computation might be more expensive.
+	///
+	/// i.e.
+	/// 1M gas tx with `gas_price=30*min` has the same priority
+	/// as 32k gas tx with `gas_price=min`
+	GasFactorAndGasPrice,
+}
+
 /// `TransactionQueue` implementation
 pub struct TransactionQueue {
+	/// Prioritization strategy for this queue
+	strategy: PrioritizationStrategy,
 	/// Gas Price threshold for transactions that can be imported to this queue (defaults to 0)
 	minimal_gas_price: U256,
 	/// The maximum amount of gas any individual transaction may use.
@@ -370,18 +416,18 @@ pub struct TransactionQueue {

 impl Default for TransactionQueue {
 	fn default() -> Self {
-		TransactionQueue::new()
+		TransactionQueue::new(PrioritizationStrategy::GasPriceOnly)
 	}
 }

 impl TransactionQueue {
 	/// Creates new instance of this Queue
-	pub fn new() -> Self {
-		Self::with_limits(1024, !U256::zero())
+	pub fn new(strategy: PrioritizationStrategy) -> Self {
+		Self::with_limits(strategy, 1024, !U256::zero())
 	}

 	/// Create new instance of this Queue with specified limits
-	pub fn with_limits(limit: usize, tx_gas_limit: U256) -> Self {
+	pub fn with_limits(strategy: PrioritizationStrategy, limit: usize, tx_gas_limit: U256) -> Self {
 		let current = TransactionSet {
 			by_priority: BTreeSet::new(),
 			by_address: Table::new(),
@@ -395,6 +441,7 @@ impl TransactionQueue {
 		};

 		TransactionQueue {
+			strategy: strategy,
 			minimal_gas_price: U256::zero(),
 			tx_gas_limit: tx_gas_limit,
 			gas_limit: !U256::zero(),
@@ -560,7 +607,7 @@ impl TransactionQueue {
 		};
 		for k in nonces_from_sender {
 			let order = self.future.drop(&sender, &k).unwrap();
-			self.current.insert(sender, k, order.penalize());
+			self.future.insert(sender, k, order.penalize());
 		}
 	}

@@ -658,6 +705,15 @@ impl TransactionQueue {
 			.collect()
 	}

+	#[cfg(test)]
+	fn future_transactions(&self) -> Vec<SignedTransaction> {
+		self.future.by_priority
+			.iter()
+			.map(|t| self.by_hash.get(&t.hash).expect("All transactions in `current` and `future` are always included in `by_hash`"))
+			.map(|t| t.transaction.clone())
+			.collect()
+	}
+
 	/// Returns hashes of all transactions from current, ordered by priority.
 	pub fn pending_hashes(&self) -> Vec<H256> {
 		self.current.by_priority
@@ -736,6 +792,7 @@ impl TransactionQueue {
 			return Err(TransactionError::AlreadyImported);
 		}

+		let min_gas_price = (self.minimal_gas_price, self.strategy);
 		let address = tx.sender();
 		let nonce = tx.nonce();
 		let hash = tx.hash();
@@ -763,7 +820,7 @@ impl TransactionQueue {
 		if nonce > next_nonce {
 			// We have a gap - put to future.
 			// Insert transaction (or replace old one with lower gas price)
-			try!(check_too_cheap(Self::replace_transaction(tx, state_nonce, &mut self.future, &mut self.by_hash)));
+			try!(check_too_cheap(Self::replace_transaction(tx, state_nonce, min_gas_price, &mut self.future, &mut self.by_hash)));
 			// Enforce limit in Future
 			let removed = self.future.enforce_limit(&mut self.by_hash);
 			// Return an error if this transaction was not imported because of limit.
@@ -779,7 +836,7 @@ impl TransactionQueue {
 		self.move_matching_future_to_current(address, nonce + U256::one(), state_nonce);

 		// Replace transaction if any
-		try!(check_too_cheap(Self::replace_transaction(tx, state_nonce, &mut self.current, &mut self.by_hash)));
+		try!(check_too_cheap(Self::replace_transaction(tx, state_nonce, min_gas_price, &mut self.current, &mut self.by_hash)));
 		// Keep track of highest nonce stored in current
 		let new_max = self.last_nonces.get(&address).map_or(nonce, |n| cmp::max(nonce, *n));
 		self.last_nonces.insert(address, new_max);
@@ -815,8 +872,8 @@ impl TransactionQueue {
 	///
 	/// Returns `true` if transaction actually got to the queue (`false` if there was already a transaction with higher
 	/// gas_price)
-	fn replace_transaction(tx: VerifiedTransaction, base_nonce: U256, set: &mut TransactionSet, by_hash: &mut HashMap<H256, VerifiedTransaction>) -> bool {
-		let order = TransactionOrder::for_transaction(&tx, base_nonce);
+	fn replace_transaction(tx: VerifiedTransaction, base_nonce: U256, min_gas_price: (U256, PrioritizationStrategy), set: &mut TransactionSet, by_hash: &mut HashMap<H256, VerifiedTransaction>) -> bool {
+		let order = TransactionOrder::for_transaction(&tx, base_nonce, min_gas_price.0, min_gas_price.1);
 		let hash = tx.hash();
 		let address = tx.sender();
 		let nonce = tx.nonce();
@@ -982,6 +1039,10 @@ mod test {
 		assert_eq!(TransactionOrigin::External.cmp(&TransactionOrigin::RetractedBlock), Ordering::Greater);
 	}

+	fn transaction_order(tx: &VerifiedTransaction, nonce: U256) -> TransactionOrder {
+		TransactionOrder::for_transaction(tx, nonce, 0.into(), PrioritizationStrategy::GasPriceOnly)
+	}
+
 	#[test]
 	fn should_create_transaction_set() {
 		// given
@@ -1002,9 +1063,9 @@ mod test {
 			x
 		};
 		// Insert both transactions
-		let order1 = TransactionOrder::for_transaction(&tx1, U256::zero());
+		let order1 = transaction_order(&tx1, U256::zero());
 		set.insert(tx1.sender(), tx1.nonce(), order1.clone());
-		let order2 = TransactionOrder::for_transaction(&tx2, U256::zero());
+		let order2 = transaction_order(&tx2, U256::zero());
 		set.insert(tx2.sender(), tx2.nonce(), order2.clone());
 		assert_eq!(set.by_priority.len(), 2);
 		assert_eq!(set.by_address.len(), 2);
@@ -1043,12 +1104,12 @@ mod test {
 			x
 		};
 		// Insert both transactions
-		let order1 = TransactionOrder::for_transaction(&tx1, U256::zero());
+		let order1 = transaction_order(&tx1, U256::zero());
 		set.insert(tx1.sender(), tx1.nonce(), order1.clone());
 		assert_eq!(set.by_priority.len(), 1);
 		assert_eq!(set.by_address.len(), 1);
 		// Two different orders (imagine nonce changed in the meantime)
-		let order2 = TransactionOrder::for_transaction(&tx2, U256::one());
+		let order2 = transaction_order(&tx2, U256::one());
 		set.insert(tx2.sender(), tx2.nonce(), order2.clone());
 		assert_eq!(set.by_priority.len(), 1);
 		assert_eq!(set.by_address.len(), 1);
@@ -1063,7 +1124,7 @@ mod test {
 	#[test]
 	fn should_handle_same_transaction_imported_twice_with_different_state_nonces() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let (tx, tx2) = new_similar_txs();
 		let prev_nonce = |a: &Address| AccountDetails{ nonce: default_nonce(a).nonce - U256::one(), balance:
 			!U256::zero() };
@@ -1088,7 +1149,7 @@ mod test {
 	#[test]
 	fn should_move_all_transactions_from_future() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let (tx, tx2) = new_txs_with_gas_price_diff(1.into(), 1.into());
 		let prev_nonce = |a: &Address| AccountDetails{ nonce: default_nonce(a).nonce - U256::one(), balance:
 			!U256::zero() };
@@ -1114,7 +1175,7 @@ mod test {
 	#[test]
 	fn should_import_tx() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let tx = new_tx();

 		// when
@@ -1129,7 +1190,7 @@ mod test {
 	#[test]
 	fn should_order_by_gas() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::new(PrioritizationStrategy::GasAndGasPrice);
 		let tx1 = new_tx_with_gas(50000.into(), 40.into());
 		let tx2 = new_tx_with_gas(40000.into(), 30.into());
 		let tx3 = new_tx_with_gas(30000.into(), 10.into());
@@ -1159,10 +1220,45 @@ mod test {
 		assert_eq!(txq.top_transactions()[2].gas_price, 20.into());
 	}

+	#[test]
+	fn should_order_by_gas_factor() {
+		// given
+		let mut txq = TransactionQueue::new(PrioritizationStrategy::GasFactorAndGasPrice);
+
+		let tx1 = new_tx_with_gas(150_000.into(), 40.into());
+		let tx2 = new_tx_with_gas(40_000.into(), 16.into());
+		let tx3 = new_tx_with_gas(30_000.into(), 15.into());
+		let tx4 = new_tx_with_gas(150_000.into(), 62.into());
+		txq.set_minimal_gas_price(15.into());
+
+		// when
+		let res1 = txq.add(tx1, &default_nonce, TransactionOrigin::External);
+		let res2 = txq.add(tx2, &default_nonce, TransactionOrigin::External);
+		let res3 = txq.add(tx3, &default_nonce, TransactionOrigin::External);
+		let res4 = txq.add(tx4, &default_nonce, TransactionOrigin::External);
+
+		// then
+		assert_eq!(res1.unwrap(), TransactionImportResult::Current);
+		assert_eq!(res2.unwrap(), TransactionImportResult::Current);
+		assert_eq!(res3.unwrap(), TransactionImportResult::Current);
+		assert_eq!(res4.unwrap(), TransactionImportResult::Current);
+		let stats = txq.status();
+		assert_eq!(stats.pending, 4);
+		println!("{:?}", txq.top_transactions());
+		assert_eq!(txq.top_transactions()[0].gas, 30_000.into());
+		assert_eq!(txq.top_transactions()[1].gas, 150_000.into());
+		assert_eq!(txq.top_transactions()[2].gas, 40_000.into());
+		assert_eq!(txq.top_transactions()[3].gas, 150_000.into());
+		assert_eq!(txq.top_transactions()[0].gas_price, 15.into());
+		assert_eq!(txq.top_transactions()[1].gas_price, 62.into());
+		assert_eq!(txq.top_transactions()[2].gas_price, 16.into());
+		assert_eq!(txq.top_transactions()[3].gas_price, 40.into());
+	}
+
 	#[test]
 	fn gas_limit_should_never_overflow() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		txq.set_gas_limit(U256::zero());
 		assert_eq!(txq.gas_limit, U256::zero());

@@ -1176,7 +1272,7 @@ mod test {
 	#[test]
 	fn should_not_import_transaction_above_gas_limit() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let tx = new_tx();
 		let gas = tx.gas;
 		let limit = gas / U256::from(2);
@@ -1198,7 +1294,7 @@ mod test {
 	#[test]
 	fn should_drop_transactions_from_senders_without_balance() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let tx = new_tx();
 		let account = |a: &Address| AccountDetails {
 			nonce: default_nonce(a).nonce,
@@ -1221,7 +1317,7 @@ mod test {
 	#[test]
 	fn should_not_import_transaction_below_min_gas_price_threshold_if_external() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let tx = new_tx();
 		txq.set_minimal_gas_price(tx.gas_price + U256::one());

@@ -1241,7 +1337,7 @@ mod test {
 	#[test]
 	fn should_import_transaction_below_min_gas_price_threshold_if_local() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let tx = new_tx();
 		txq.set_minimal_gas_price(tx.gas_price + U256::one());

@@ -1258,7 +1354,7 @@ mod test {
 	#[test]
 	fn should_reject_incorrectly_signed_transaction() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let tx = new_unsigned_tx(U256::from(123));
 		let stx = {
 			let mut s = RlpStream::new_list(9);
@@ -1283,7 +1379,7 @@ mod test {
 	#[test]
 	fn should_import_txs_from_same_sender() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();

 		let (tx, tx2) = new_txs(U256::from(1));

@@ -1301,7 +1397,7 @@ mod test {
 	#[test]
 	fn should_prioritize_local_transactions_within_same_nonce_height() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let tx = new_tx();
 		// the second one has same nonce but higher `gas_price`
 		let (_, tx2) = new_similar_txs();
@@ -1322,7 +1418,7 @@ mod test {
 	#[test]
 	fn should_prioritize_reimported_transactions_within_same_nonce_height() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let tx = new_tx();
 		// the second one has same nonce but higher `gas_price`
 		let (_, tx2) = new_similar_txs();
@@ -1343,7 +1439,7 @@ mod test {
 	#[test]
 	fn should_not_prioritize_local_transactions_with_different_nonce_height() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let (tx, tx2) = new_txs(U256::from(1));

 		// when
@@ -1357,10 +1453,40 @@ mod test {
 		assert_eq!(top.len(), 2);
 	}

+	#[test]
+	fn should_penalize_transactions_from_sender_in_future() {
+		// given
+		let prev_nonce = |a: &Address| AccountDetails{ nonce: default_nonce(a).nonce - U256::one(), balance: !U256::zero() };
+		let mut txq = TransactionQueue::default();
+		// txa, txb - slightly bigger gas price to have consistent ordering
+		let (txa, txb) = new_txs(U256::from(1));
+		let (tx1, tx2) = new_txs_with_higher_gas_price(U256::from(3));
+
+		// insert everything
+		txq.add(txa.clone(), &prev_nonce, TransactionOrigin::External).unwrap();
+		txq.add(txb.clone(), &prev_nonce, TransactionOrigin::External).unwrap();
+		txq.add(tx1.clone(), &prev_nonce, TransactionOrigin::External).unwrap();
+		txq.add(tx2.clone(), &prev_nonce, TransactionOrigin::External).unwrap();
+
+		assert_eq!(txq.status().future, 4);
+
+		// when
+		txq.penalize(&tx1.hash());
+
+		// then
+		let top = txq.future_transactions();
+		assert_eq!(top[0], txa);
+		assert_eq!(top[1], txb);
+		assert_eq!(top[2], tx1);
+		assert_eq!(top[3], tx2);
+		assert_eq!(top.len(), 4);
+	}
+
+
 	#[test]
 	fn should_penalize_transactions_from_sender() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		// txa, txb - slightly bigger gas price to have consistent ordering
 		let (txa, txb) = new_txs(U256::from(1));
 		let (tx1, tx2) = new_txs_with_higher_gas_price(U256::from(3));
@@ -1393,7 +1519,7 @@ mod test {
 	#[test]
 	fn should_return_pending_hashes() {
 			// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();

 		let (tx, tx2) = new_txs(U256::from(1));

@@ -1411,7 +1537,7 @@ mod test {
 	#[test]
 	fn should_put_transaction_to_futures_if_gap_detected() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();

 		let (tx, tx2) = new_txs(U256::from(2));

@@ -1437,7 +1563,7 @@ mod test {
 			!U256::zero() };
 		let next2_nonce = default_nonce_val() + U256::from(3);

-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();

 		let (tx, tx2) = new_txs(U256::from(1));
 		txq.add(tx.clone(), &prev_nonce, TransactionOrigin::External).unwrap();
@@ -1456,7 +1582,7 @@ mod test {
 	#[test]
 	fn should_move_transactions_if_gap_filled() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let kp = KeyPair::create().unwrap();
 		let secret = kp.secret();
 		let tx = new_unsigned_tx(U256::from(123)).sign(secret);
@@ -1480,7 +1606,7 @@ mod test {
 	#[test]
 	fn should_remove_transaction() {
 		// given
-		let mut txq2 = TransactionQueue::new();
+		let mut txq2 = TransactionQueue::default();
 		let (tx, tx2) = new_txs(U256::from(3));
 		txq2.add(tx.clone(), &default_nonce, TransactionOrigin::External).unwrap();
 		txq2.add(tx2.clone(), &default_nonce, TransactionOrigin::External).unwrap();
@@ -1501,7 +1627,7 @@ mod test {
 	#[test]
 	fn should_move_transactions_to_future_if_gap_introduced() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let (tx, tx2) = new_txs(U256::from(1));
 		let tx3 = new_tx();
 		txq.add(tx2.clone(), &default_nonce, TransactionOrigin::External).unwrap();
@@ -1522,7 +1648,7 @@ mod test {
 	#[test]
 	fn should_clear_queue() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let (tx, tx2) = new_txs(U256::one());

 		// add
@@ -1542,7 +1668,7 @@ mod test {
 	#[test]
 	fn should_drop_old_transactions_when_hitting_the_limit() {
 		// given
-		let mut txq = TransactionQueue::with_limits(1, !U256::zero());
+		let mut txq = TransactionQueue::with_limits(PrioritizationStrategy::GasPriceOnly, 1, !U256::zero());
 		let (tx, tx2) = new_txs(U256::one());
 		let sender = tx.sender().unwrap();
 		let nonce = tx.nonce;
@@ -1564,7 +1690,7 @@ mod test {
 	#[test]
 	fn should_return_correct_nonces_when_dropped_because_of_limit() {
 		// given
-		let mut txq = TransactionQueue::with_limits(2, !U256::zero());
+		let mut txq = TransactionQueue::with_limits(PrioritizationStrategy::GasPriceOnly, 2, !U256::zero());
 		let tx = new_tx();
 		let (tx1, tx2) = new_txs(U256::one());
 		let sender = tx1.sender().unwrap();
@@ -1585,7 +1711,7 @@ mod test {

 	#[test]
 	fn should_limit_future_transactions() {
-		let mut txq = TransactionQueue::with_limits(1, !U256::zero());
+		let mut txq = TransactionQueue::with_limits(PrioritizationStrategy::GasPriceOnly, 1, !U256::zero());
 		txq.current.set_limit(10);
 		let (tx1, tx2) = new_txs_with_gas_price_diff(U256::from(4), U256::from(1));
 		let (tx3, tx4) = new_txs_with_gas_price_diff(U256::from(4), U256::from(2));
@@ -1604,7 +1730,7 @@ mod test {

 	#[test]
 	fn should_drop_transactions_with_old_nonces() {
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let tx = new_tx();
 		let last_nonce = tx.nonce + U256::one();
 		let fetch_last_nonce = |_a: &Address| AccountDetails{ nonce: last_nonce, balance: !U256::zero() };
@@ -1624,7 +1750,7 @@ mod test {
 		// given
 		let nonce = |a: &Address| AccountDetails { nonce: default_nonce(a).nonce + U256::one(),
 			balance: !U256::zero() };
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let (_tx1, tx2) = new_txs(U256::from(1));
 		txq.add(tx2.clone(), &default_nonce, TransactionOrigin::External).unwrap();
 		assert_eq!(txq.status().future, 1);
@@ -1643,7 +1769,7 @@ mod test {
 	#[test]
 	fn should_accept_same_transaction_twice_if_removed() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let (tx1, tx2) = new_txs(U256::from(1));
 		txq.add(tx1.clone(), &default_nonce, TransactionOrigin::External).unwrap();
 		txq.add(tx2.clone(), &default_nonce, TransactionOrigin::External).unwrap();
@@ -1664,7 +1790,7 @@ mod test {
 	#[test]
 	fn should_not_move_to_future_if_state_nonce_is_higher() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let (tx, tx2) = new_txs(U256::from(1));
 		let tx3 = new_tx();
 		txq.add(tx2.clone(), &default_nonce, TransactionOrigin::External).unwrap();
@@ -1687,7 +1813,7 @@ mod test {
 	fn should_replace_same_transaction_when_has_higher_fee() {
 		init_log();
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let keypair = KeyPair::create().unwrap();
 		let tx = new_unsigned_tx(U256::from(123)).sign(keypair.secret());
 		let tx2 = {
@@ -1710,7 +1836,7 @@ mod test {
 	#[test]
 	fn should_replace_same_transaction_when_importing_to_futures() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let keypair = KeyPair::create().unwrap();
 		let tx0 = new_unsigned_tx(U256::from(123)).sign(keypair.secret());
 		let tx1 = {
@@ -1744,7 +1870,7 @@ mod test {
 			!U256::zero() };
 		let next_nonce = |a: &Address| AccountDetails{ nonce: default_nonce(a).nonce + U256::one(), balance:
 			!U256::zero() };
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let (tx1, tx2) = new_txs(U256::one());
 		txq.add(tx1.clone(), &previous_nonce, TransactionOrigin::External).unwrap();
 		txq.add(tx2, &previous_nonce, TransactionOrigin::External).unwrap();
@@ -1762,7 +1888,7 @@ mod test {
 	#[test]
 	fn should_return_none_when_transaction_from_given_address_does_not_exist() {
 		// given
-		let txq = TransactionQueue::new();
+		let txq = TransactionQueue::default();

 		// then
 		assert_eq!(txq.last_nonce(&Address::default()), None);
@@ -1771,7 +1897,7 @@ mod test {
 	#[test]
 	fn should_return_correct_nonce_when_transactions_from_given_address_exist() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let tx = new_tx();
 		let from = tx.sender().unwrap();
 		let nonce = tx.nonce;
@@ -1787,7 +1913,7 @@ mod test {
 	#[test]
 	fn should_remove_old_transaction_even_if_newer_transaction_was_not_known() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let (tx1, tx2) = new_txs(U256::one());
 		let (nonce1, nonce2) = (tx1.nonce, tx2.nonce);
 		let details1 = |_a: &Address| AccountDetails { nonce: nonce1, balance: !U256::zero() };
@@ -1805,7 +1931,7 @@ mod test {
 	#[test]
 	fn should_return_valid_last_nonce_after_remove_all() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let (tx1, tx2) = new_txs(U256::from(4));
 		let sender = tx1.sender().unwrap();
 		let (nonce1, nonce2) = (tx1.nonce, tx2.nonce);
@@ -1829,7 +1955,7 @@ mod test {
 	#[test]
 	fn should_return_true_if_there_is_local_transaction_pending() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let (tx1, tx2) = new_txs(U256::from(1));
 		assert_eq!(txq.has_local_pending_transactions(), false);

@@ -1845,7 +1971,7 @@ mod test {
 	#[test]
 	fn should_keep_right_order_in_future() {
 		// given
-		let mut txq = TransactionQueue::with_limits(1, !U256::zero());
+		let mut txq = TransactionQueue::with_limits(PrioritizationStrategy::GasPriceOnly, 1, !U256::zero());
 		let (tx1, tx2) = new_txs(U256::from(1));
 		let prev_nonce = |a: &Address| AccountDetails { nonce: default_nonce(a).nonce - U256::one(), balance:
 			default_nonce(a).balance };
@@ -1862,7 +1988,7 @@ mod test {
 	#[test]
 	fn should_return_correct_last_nonce() {
 		// given
-		let mut txq = TransactionQueue::new();
+		let mut txq = TransactionQueue::default();
 		let (tx1, tx2, tx2_2, tx3) = {
 			let keypair = KeyPair::create().unwrap();
 			let secret = &keypair.secret();
--- 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};
@@ -38,42 +38,93 @@ pub struct ApplyOutcome {
 /// Result type for the execution ("application") of a transaction.
 pub type ApplyResult = Result<ApplyOutcome, Error>;

-#[derive(Debug)]
-enum AccountEntry {
-	/// Contains account data.
-	Cached(Account),
-	/// Account has been deleted.
-	Killed,
-	/// Account does not exist.
-	Missing,
+#[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 {
-		match *self {
-			AccountEntry::Cached(ref a) => a.is_dirty(),
-			AccountEntry::Killed => true,
-			AccountEntry::Missing => false,
-		}
+		self.state == AccountState::Dirty
 	}

-	/// Clone dirty data into new `AccountEntry`.
+	/// Clone dirty data into new `AccountEntry`. This includes
+	/// basic account data and modified storage keys.
 	/// Returns None if clean.
-	fn clone_dirty(&self) -> Option<AccountEntry> {
-		match *self {
-			AccountEntry::Cached(ref acc) if acc.is_dirty() => Some(AccountEntry::Cached(acc.clone_dirty())),
-			AccountEntry::Killed => Some(AccountEntry::Killed),
-			_ => None,
+	fn clone_if_dirty(&self) -> Option<AccountEntry> {
+		match self.is_dirty() {
+			true => Some(self.clone_dirty()),
+			false => None,
 		}
 	}

-	/// Clone account entry data that needs to be saved in the snapshot.
-	/// This includes basic account information and all locally cached storage keys
-	fn clone_for_snapshot(&self) -> AccountEntry {
-		match *self {
-			AccountEntry::Cached(ref acc) => AccountEntry::Cached(acc.clone_all()),
-			AccountEntry::Killed => AccountEntry::Killed,
-			AccountEntry::Missing => AccountEntry::Missing,
+	/// 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,
 		}
 	}
 }
@@ -86,6 +137,9 @@ impl AccountEntry {
 /// 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
@@ -99,12 +153,32 @@ impl AccountEntry {
 /// 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: StateDB,
 	root: H256,
 	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,
@@ -158,35 +232,48 @@ 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);
+				if prev.is_empty() {
+					**prev = snapshot;
+				} else {
+					for (k, v) in snapshot.drain() {
+						prev.entry(k).or_insert(v);
+					}
 				}
 			}
 		}
 	}

-	/// Revert to snapshot
-	pub fn revert_snapshot(&mut self) {
+	/// 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) => {
-						self.cache.borrow_mut().insert(k, 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) {
-							::std::collections::hash_map::Entry::Occupied(e) => {
+							Entry::Occupied(e) => {
 								if e.get().is_dirty() {
 									e.remove();
 								}
@@ -200,10 +287,17 @@ impl State {
 	}

 	fn insert_cache(&self, address: &Address, account: AccountEntry) {
-		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;
+		// 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);
@@ -212,14 +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).map(AccountEntry::clone_for_snapshot));
+				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(mut self) -> (H256, StateDB) {
-		self.commit_cache();
+		self.update_shared_cache();
 		(self.root, self.db)
 	}

@@ -231,12 +325,12 @@ 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, AccountEntry::Cached(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, AccountEntry::Killed);
+		self.insert_cache(account, AccountEntry::new_dirty(None));
 	}

 	/// Determine whether an account exists.
@@ -271,8 +365,8 @@ impl State {
 			let local_cache = self.cache.borrow_mut();
 			let mut local_account = None;
 			if let Some(maybe_acc) = local_cache.get(address) {
-				match *maybe_acc {
-					AccountEntry::Cached(ref account) => {
+				match maybe_acc.account {
+					Some(ref account) => {
 						if let Some(value) = account.cached_storage_at(key) {
 							return value;
 						} else {
@@ -288,7 +382,7 @@ impl State {
 				return result;
 			}
 			if let Some(ref mut acc) = local_account {
-				if let AccountEntry::Cached(ref account) = **acc {
+				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()
@@ -303,10 +397,7 @@ impl State {
 			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));
-		match maybe_acc {
-			Some(account) => self.insert_cache(address, AccountEntry::Cached(account)),
-			None => self.insert_cache(address, AccountEntry::Missing),
-		}
+		self.insert_cache(address, AccountEntry::new_clean(maybe_acc));
 		r
 	}

@@ -330,13 +421,17 @@ impl State {
 	/// 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`.
@@ -352,7 +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`.
@@ -392,10 +489,9 @@ impl State {
 		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 AccountEntry::Cached(ref mut account) if account.is_dirty() => {
+		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);
@@ -407,17 +503,15 @@ impl State {

 		{
 			let mut trie = trie_factory.from_existing(db.as_hashdb_mut(), root).unwrap();
-			for (address, ref mut a) in accounts.iter_mut() {
-				match **a {
-					AccountEntry::Cached(ref mut account) if account.is_dirty() => {
-						account.set_clean();
+			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()));
 					},
-					AccountEntry::Killed => {
+					None => {
 						try!(trie.remove(address));
-						**a = AccountEntry::Missing;
 					},
-					_ => {},
 				}
 			}
 		}
@@ -425,20 +519,12 @@ impl State {
 		Ok(())
 	}

-	fn commit_cache(&mut self) {
+	/// Merge local cache into shared canonical state cache.
+	fn update_shared_cache(&mut self) {
 		let mut addresses = self.cache.borrow_mut();
-		for (address, a) in addresses.drain() {
-			match a {
-				AccountEntry::Cached(account) => {
-					if !account.is_dirty() {
-						self.db.cache_account(address, Some(account));
-					}
-				},
-				AccountEntry::Missing => {
-					self.db.cache_account(address, None);
-				},
-				_ => {},
-			}
+		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);
 		}
 	}

@@ -460,7 +546,7 @@ impl State {
 		assert!(self.snapshots.borrow().is_empty());
 		for (add, acc) in accounts.drain().into_iter() {
 			self.db.note_account_bloom(&add);
-			self.cache.borrow_mut().insert(add, AccountEntry::Cached(Account::from_pod(acc)));
+			self.cache.borrow_mut().insert(add, AccountEntry::new_dirty(Some(Account::from_pod(acc))));
 		}
 	}

@@ -470,7 +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 AccountEntry::Cached(ref acc) = *opt {
+			if let Some(ref acc) = opt.account {
 				m.insert(add.clone(), PodAccount::from_account(acc));
 			}
 			m
@@ -519,7 +605,7 @@ impl State {
 		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 AccountEntry::Cached(ref mut account) = **maybe_acc {
+			if let Some(ref mut account) = maybe_acc.account {
 				Self::update_account_cache(require, account, a, self.db.as_hashdb());
 				return f(Some(account));
 			}
@@ -546,10 +632,7 @@ impl State {
 					Self::update_account_cache(require, account, a, self.db.as_hashdb());
 				}
 				let r = f(maybe_acc.as_ref());
-				match maybe_acc {
-					Some(account) => self.insert_cache(a, AccountEntry::Cached(account)),
-					None => self.insert_cache(a, AccountEntry::Missing),
-				}
+				self.insert_cache(a, AccountEntry::new_clean(maybe_acc));
 				r
 			}
 		}
@@ -568,36 +651,38 @@ impl State {
 		let contains_key = self.cache.borrow().contains_key(a);
 		if !contains_key {
 			match self.db.get_cached_account(a) {
-				Some(Some(acc)) => self.insert_cache(a, AccountEntry::Cached(acc)),
-				Some(None) => self.insert_cache(a, AccountEntry::Missing),
+				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::Cached(Account::from_rlp(acc)),
-							Ok(None) => AccountEntry::Missing,
+							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::Missing
+						AccountEntry::new_clean(None)
 					};
 					self.insert_cache(a, maybe_acc);
 				}
 			}
-		} else {
-			self.note_cache(a);
-		}
-
-		match self.cache.borrow_mut().get_mut(a).unwrap() {
-			&mut AccountEntry::Cached(ref mut acc) => not_default(acc),
-			slot => *slot = AccountEntry::Cached(default()),
+		}
+		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| {
-			match c.get_mut(a).unwrap() {
-				&mut AccountEntry::Cached(ref mut account) => {
+			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));
@@ -621,7 +706,7 @@ impl Clone for 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_dirty() {
+				if let Some(entry) = val.clone_if_dirty() {
 					cache.insert(key.clone(), entry);
 				}
 			}
@@ -1677,12 +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));
 }

@@ -1695,9 +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
@@ -14,22 +14,53 @@
 // 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 util::{Arc, Address, DBTransaction, UtilError, Mutex, Hashable, BytesConvertable};
 use account::Account;
+use header::BlockNumber;
+use util::{Arc, Address, Database, DBTransaction, UtilError, Mutex, Hashable, BytesConvertable};
 use bloomfilter::{Bloom, BloomJournal};
-use util::Database;
 use client::DB_COL_ACCOUNT_BLOOM;
 use byteorder::{LittleEndian, ByteOrder};

-const STATE_CACHE_ITEMS: usize = 65536;
+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.
@@ -39,11 +70,21 @@ struct AccountCache {
 /// 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>>,
-	cache_overlay: Vec<(Address, Option<Account>)>,
-	is_canon: bool,
+	/// 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;
@@ -52,6 +93,8 @@ 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");
@@ -82,10 +125,15 @@ impl StateDB {
 		let bloom = Self::load_bloom(db.backing());
 		StateDB {
 			db: db,
-			account_cache: Arc::new(Mutex::new(AccountCache { accounts: LruCache::new(STATE_CACHE_ITEMS) })),
-			cache_overlay: Vec::new(),
-			is_canon: false,
+			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,
 		}
 	}

@@ -124,14 +172,106 @@ impl StateDB {
 		}

 		let records = try!(self.db.commit(batch, now, id, end));
-		if self.is_canon {
-			self.commit_cache();
-		} else {
-			self.clear_cache();
-		}
+		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()
@@ -147,20 +287,24 @@ impl StateDB {
 		StateDB {
 			db: self.db.boxed_clone(),
 			account_cache: self.account_cache.clone(),
-			cache_overlay: Vec::new(),
-			is_canon: false,
+			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) -> StateDB {
+	pub fn boxed_clone_canon(&self, parent: &H256) -> StateDB {
 		StateDB {
 			db: self.db.boxed_clone(),
 			account_cache: self.account_cache.clone(),
-			cache_overlay: Vec::new(),
-			is_canon: true,
+			cache_buffer: Vec::new(),
 			account_bloom: self.account_bloom.clone(),
+			parent_hash: Some(parent.clone()),
+			commit_hash: None,
+			commit_number: None,
 		}
 	}

@@ -179,53 +323,147 @@ impl StateDB {
 		&*self.db
 	}

-	/// Enqueue cache change.
-	pub fn cache_account(&mut self, addr: Address, data: Option<Account>) {
-		self.cache_overlay.push((addr, data));
-	}
-
-	/// Apply pending cache changes.
-	fn commit_cache(&mut self) {
-		let mut cache = self.account_cache.lock();
-		for (address, account) in self.cache_overlay.drain(..) {
-			if let Some(&mut Some(ref mut existing)) = cache.accounts.get_mut(&address) {
-				if let Some(new) = account {
-					existing.merge_with(new);
-					continue;
-				}
-			}
-			cache.accounts.insert(address, account);
-		}
-	}
-
-	/// Clear the cache.
-	pub fn clear_cache(&mut self) {
-		self.cache_overlay.clear();
-		let mut cache = self.account_cache.lock();
-		cache.accounts.clear();
+	/// 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 the state is non-canonical and cache is disabled
-	/// or if the account is not cached.
+	/// Returns 'None' if cache is disabled or if the account is not cached.
 	pub fn get_cached_account(&self, addr: &Address) -> Option<Option<Account>> {
-		if !self.is_canon {
+		let mut cache = self.account_cache.lock();
+		if !Self::is_allowed(addr, &self.parent_hash, &cache.modifications) {
 			return None;
 		}
-		let mut cache = self.account_cache.lock();
 		cache.accounts.get_mut(&addr).map(|a| a.as_ref().map(|a| a.clone_basic()))
 	}

 	/// Get value from a cached account.
-	/// Returns 'None' if the state is non-canonical and cache is disabled
-	/// or if the account is not cached.
+	/// 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 {
-		if !self.is_canon {
+		let mut cache = self.account_cache.lock();
+		if !Self::is_allowed(a, &self.parent_hash, &cache.modifications) {
 			return None;
 		}
-		let mut cache = self.account_cache.lock();
 		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/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/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/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 3
+!define VERSIONBUILD 4

 !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/migration.rs
+++ b/parity/migration.rs
@@ -270,10 +270,13 @@ pub fn migrate(path: &Path, pruning: Algorithm, compaction_profile: CompactionPr
 		println!("Migration finished");
 	}

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

-	// update version file.
-	update_version(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/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)>>())
@@ -437,7 +437,7 @@ impl<C, S: ?Sized, M, EM> Eth for EthClient<C, S, M, EM> where
 				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(&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),
@@ -462,8 +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);
@@ -509,7 +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/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()
 	}

--- 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/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 = "1.3.3"
+version = "1.3.4"
 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/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>) {
Author	SHA1	Message	Date
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