Backports for 2.1.0 beta (#9518)

* parity-version: mark 2.1.0 track beta * ci: update branch version references * docker: release master to latest * Fix checkpointing when creating contract failed (#9514) * ci: fix json docs generation (#9515) * fix typo in version string (#9516) * Update patricia trie to 0.2.2 crates. Default dependencies on minor version only. * Putting back ethereum tests to the right commit * Enable all Constantinople hard fork changes in constantinople_test.json (#9505) * Enable all Constantinople hard fork changes in constantinople_test.json * Address grumbles * Remove EIP-210 activation * 8m -> 5m * Temporarily add back eip210 transition so we can get test passed * Add eip210_test and remove eip210 transition from const_test * In create memory calculation is the same for create2 because the additional parameter was popped before. (#9522) * deps: bump fs-swap and kvdb-rocksdb * Multithreaded snapshot creation (#9239) * Add Progress to Snapshot Secondary chunks creation * Use half of CPUs to multithread snapshot creation * Use env var to define number of threads * info to debug logs * Add Snapshot threads as CLI option * Randomize chunks per thread * Remove randomness, add debugging * Add warning * Add tracing * Use parity-common fix seek branch * Fix log * Fix tests * Fix tests * PR Grumbles * PR Grumble II * Update Cargo.lock * PR Grumbles * Default snapshot threads to half number of CPUs * Fix default snapshot threads // min 1 * correct before_script for nightly build versions (#9543) - fix gitlab array of strings syntax error - get proper commit id - avoid colon in stings * Remove initial token for WS. (#9545) * version: mark release critical * ci: fix rpc docs generation 2 (#9550) * Improve P2P discovery (#9526) * Add `target` to Rust traces * network-devp2p: Don't remove discovery peer in main sync * network-p2p: Refresh discovery more often * Update Peer discovery protocol * Run discovery more often when not enough nodes connected * Start the first discovery early * Update fast discovery rate * Fix tests * Fix `ping` tests * Fixing remote Node address ; adding PingPong round * Fix tests: update new +1 PingPong round * Increase slow Discovery rate Check in flight FindNode before pings * Add `deprecated` to deprecated_echo_hash * Refactor `discovery_round` branching * net_version caches network_id to avoid redundant aquire of sync read lock (#9544) * net_version caches network_id to avoid redundant aquire of sync read lock, #8746 * use lower_hex display formatting for net_peerCount rpc method * Increase Gas-floor-target and Gas Cap (#9564) + Gas-floor-target increased to 8M by default + Gas-cap increased to 10M by default * Revert to old parity-tokio-ipc. * Downgrade named pipes.
2018-09-17 19:22:30 +02:00 · 2018-09-17 19:22:30 +02:00 · d147700046
commit d147700046
parent 631df0fe56
39 changed files with 834 additions and 598 deletions
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@ -41,17 +41,14 @@ cache:
    paths:
    - artifacts/

-.determine_version:
-  before_script:                   &determine_version
-    - >
-      VERSION="$(sed -r -n '1,/^version/s/^version = "([^"]+)".*$/\1/p' < Cargo.toml)";
-      if [ "${CI_COMMIT_REF_NAME}" = "nightly" ]; then
-        COMMIT_REF_SHORT="echo ${CI_COMMIT_REF} | grep -oE '^.{7}')";
-        DATE_STRING="$(date +%Y%m%d)";
-        export VERSION="${VERSION}-${COMMIT_REF_SHORT}-${DATE_STRING}";
-      fi;
-      export VERSION;
-      echo "Version: $VERSION"
+.determine_version:                &determine_version
+  - VERSION="$(sed -r -n '1,/^version/s/^version = "([^"]+)".*$/\1/p' Cargo.toml)"
+  - DATE_STR="$(date +%Y%m%d)"
+  - ID_SHORT="$(echo ${CI_COMMIT_SHA} | cut -c 1-7)"
+  - test "${CI_COMMIT_REF_NAME}" = "nightly" && VERSION="${VERSION}-${ID_SHORT}-${DATE_STR}"
+  - export VERSION
+  - echo "Version = ${VERSION}"
+


 #### stage:                        test
@ -256,7 +253,7 @@ publish-linux-snap-armhf:

 publish-docker-parity-amd64: &publish_docker
  stage:                           publish
-  only:                            *publishable_branches
+  only:                            *releaseable_branches
  cache: {}
  dependencies:
    - build-linux-ubuntu-amd64
--- a/Cargo.lock
+++ b/Cargo.lock
--- a/ethcore/Cargo.toml
+++ b/ethcore/Cargo.toml
@ -18,7 +18,7 @@ ethcore-bloom-journal = { path = "../util/bloom" }
 parity-bytes = "0.1"
 hashdb = "0.2.1"
 memorydb = "0.2.1"
-patricia-trie = "0.2.1"
+patricia-trie = "0.2"
 patricia-trie-ethereum = { path = "../util/patricia-trie-ethereum" }
 parity-crypto = "0.1"
 error-chain = { version = "0.12", default-features = false }
--- a/ethcore/evm/src/interpreter/gasometer.rs
+++ b/ethcore/evm/src/interpreter/gasometer.rs
@ -233,11 +233,7 @@ impl<Gas: evm::CostType> Gasometer<Gas> {
 			},
 			instructions::CREATE | instructions::CREATE2 => {
 				let gas = Gas::from(schedule.create_gas);
-				let mem = match instruction {
-					instructions::CREATE => mem_needed(stack.peek(1), stack.peek(2))?,
-					instructions::CREATE2 => mem_needed(stack.peek(2), stack.peek(3))?,
-					_ => unreachable!("instruction can only be CREATE/CREATE2 checked above; qed"),
-				};
+				let mem = mem_needed(stack.peek(1), stack.peek(2))?;

 				Request::GasMemProvide(gas, mem, None)
 			},
--- a/ethcore/light/Cargo.toml
+++ b/ethcore/light/Cargo.toml
@ -13,7 +13,7 @@ parity-bytes = "0.1"
 ethcore-transaction = { path = "../transaction" }
 ethereum-types = "0.4"
 memorydb = "0.2.1"
-patricia-trie = "0.2.1"
+patricia-trie = "0.2"
 patricia-trie-ethereum = { path = "../../util/patricia-trie-ethereum" }
 ethcore-network = { path = "../../util/network" }
 ethcore-io = { path = "../../util/io" }
--- a/ethcore/private-tx/Cargo.toml
+++ b/ethcore/private-tx/Cargo.toml
@ -26,7 +26,7 @@ heapsize = "0.4"
 keccak-hash = "0.1.2"
 log = "0.4"
 parking_lot = "0.6"
-patricia-trie = "0.2.1"
+patricia-trie = "0.2"
 patricia-trie-ethereum = { path = "../../util/patricia-trie-ethereum" }
 rand = "0.3"
 rlp = { version = "0.2.4", features = ["ethereum"] }
--- a/ethcore/res/ethereum/constantinople_test.json
+++ b/ethcore/res/ethereum/constantinople_test.json
@ -1,16 +1,16 @@
 {
-	"name": "Byzantium (Test)",
+	"name": "Constantinople (test)",
 	"engine": {
 		"Ethash": {
 			"params": {
 				"minimumDifficulty": "0x020000",
 				"difficultyBoundDivisor": "0x0800",
 				"durationLimit": "0x0d",
-				"blockReward": "0x29A2241AF62C0000",
+				"blockReward": "0x1BC16D674EC80000",
 				"homesteadTransition": "0x0",
 				"eip100bTransition": "0x0",
 				"difficultyBombDelays": {
-					"0": 3000000
+					"0": 5000000
 				}
 			}
 		}
@ -30,11 +30,13 @@
 		"eip161abcTransition": "0x0",
 		"eip161dTransition": "0x0",
 		"eip140Transition": "0x0",
-		"eip210Transition": "0x0",
 		"eip211Transition": "0x0",
 		"eip214Transition": "0x0",
 		"eip155Transition": "0x0",
 		"eip658Transition": "0x0",
+		"eip145Transition": "0x0",
+		"eip1014Transition": "0x0",
+		"eip1052Transition": "0x0",
 		"eip1283Transition": "0x0"
 	},
 	"genesis": {
--- a/ethcore/res/ethereum/eip210_test.json
+++ b/ethcore/res/ethereum/eip210_test.json
@ -0,0 +1,54 @@
+{
+	"name": "EIP210 (test)",
+	"engine": {
+		"Ethash": {
+			"params": {
+				"minimumDifficulty": "0x020000",
+				"difficultyBoundDivisor": "0x0800",
+				"durationLimit": "0x0d",
+				"blockReward": "0x4563918244F40000",
+				"homesteadTransition": "0x0"
+			}
+		}
+	},
+	"params": {
+		"gasLimitBoundDivisor": "0x0400",
+		"registrar" : "0xc6d9d2cd449a754c494264e1809c50e34d64562b",
+		"accountStartNonce": "0x00",
+		"maximumExtraDataSize": "0x20",
+		"minGasLimit": "0x1388",
+		"networkID" : "0x1",
+		"maxCodeSize": 24576,
+		"maxCodeSizeTransition": "0x0",
+		"eip98Transition": "0xffffffffffffffff",
+		"eip150Transition": "0x0",
+		"eip160Transition": "0x0",
+		"eip161abcTransition": "0x0",
+		"eip161dTransition": "0x0",
+		"eip210Transition": "0x0"
+	},
+	"genesis": {
+		"seal": {
+			"ethereum": {
+				"nonce": "0x0000000000000042",
+				"mixHash": "0x0000000000000000000000000000000000000000000000000000000000000000"
+			}
+		},
+		"difficulty": "0x400000000",
+		"author": "0x0000000000000000000000000000000000000000",
+		"timestamp": "0x00",
+		"parentHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
+		"extraData": "0x11bbe8db4e347b4e8c937c1c8370e4b5ed33adb3db69cbdb7a38e1e50b1b82fa",
+		"gasLimit": "0x1388"
+	},
+	"accounts": {
+		"0000000000000000000000000000000000000001": { "balance": "1", "builtin": { "name": "ecrecover", "pricing": { "linear": { "base": 3000, "word": 0 } } } },
+		"0000000000000000000000000000000000000002": { "balance": "1", "builtin": { "name": "sha256", "pricing": { "linear": { "base": 60, "word": 12 } } } },
+		"0000000000000000000000000000000000000003": { "balance": "1", "builtin": { "name": "ripemd160", "pricing": { "linear": { "base": 600, "word": 120 } } } },
+		"0000000000000000000000000000000000000004": { "balance": "1", "builtin": { "name": "identity", "pricing": { "linear": { "base": 15, "word": 3 } } } },
+		"0000000000000000000000000000000000000005": { "builtin": { "name": "modexp", "activate_at": "0x00", "pricing": { "modexp": { "divisor": 100 } } } },
+		"0000000000000000000000000000000000000006": { "builtin": { "name": "alt_bn128_add", "activate_at": "0x00", "pricing": { "linear": { "base": 500, "word": 0 } } } },
+		"0000000000000000000000000000000000000007": { "builtin": { "name": "alt_bn128_mul", "activate_at": "0x00", "pricing": { "linear": { "base": 2000, "word": 0 } } } },
+		"0000000000000000000000000000000000000008": { "builtin": { "name": "alt_bn128_pairing", "activate_at": "0x00", "pricing": { "alt_bn128_pairing": { "base": 100000, "pair": 80000 } } } }
+	}
+}
--- a/ethcore/src/client/client.rs
+++ b/ethcore/src/client/client.rs
@ -1153,7 +1153,8 @@ impl Client {
 			},
 		};

-		snapshot::take_snapshot(&*self.engine, &self.chain.read(), start_hash, db.as_hashdb(), writer, p)?;
+		let processing_threads = self.config.snapshot.processing_threads;
+		snapshot::take_snapshot(&*self.engine, &self.chain.read(), start_hash, db.as_hashdb(), writer, p, processing_threads)?;

 		Ok(())
 	}
--- a/ethcore/src/client/config.rs
+++ b/ethcore/src/client/config.rs
@ -19,6 +19,7 @@ use std::fmt::{Display, Formatter, Error as FmtError};

 use verification::{VerifierType, QueueConfig};
 use journaldb;
+use snapshot::SnapshotConfiguration;

 pub use std::time::Duration;
 pub use blockchain::Config as BlockChainConfig;
@ -120,6 +121,8 @@ pub struct ClientConfig {
 	pub check_seal: bool,
 	/// Maximal number of transactions queued for verification in a separate thread.
 	pub transaction_verification_queue_size: usize,
+	/// Snapshot configuration
+	pub snapshot: SnapshotConfiguration,
 }

 impl Default for ClientConfig {
@ -144,6 +147,7 @@ impl Default for ClientConfig {
 			history_mem: 32 * mb,
 			check_seal: true,
 			transaction_verification_queue_size: 8192,
+			snapshot: Default::default(),
 		}
 	}
 }
--- a/ethcore/src/ethereum/mod.rs
+++ b/ethcore/src/ethereum/mod.rs
@ -152,6 +152,9 @@ pub fn new_frontier_test_machine() -> EthereumMachine { load_machine(include_byt
 /// Create a new Foundation Homestead-era chain spec as though it never changed from Frontier.
 pub fn new_homestead_test_machine() -> EthereumMachine { load_machine(include_bytes!("../../res/ethereum/homestead_test.json")) }

+/// Create a new Foundation Homestead-EIP210-era chain spec as though it never changed from Homestead/Frontier.
+pub fn new_eip210_test_machine() -> EthereumMachine { load_machine(include_bytes!("../../res/ethereum/eip210_test.json")) }
+
 /// Create a new Foundation Byzantium era spec.
 pub fn new_byzantium_test_machine() -> EthereumMachine { load_machine(include_bytes!("../../res/ethereum/byzantium_test.json")) }

--- a/ethcore/src/snapshot/consensus/authority.rs
+++ b/ethcore/src/snapshot/consensus/authority.rs
@ -30,7 +30,7 @@ use machine::EthereumMachine;
 use ids::BlockId;
 use header::Header;
 use receipt::Receipt;
-use snapshot::{Error, ManifestData};
+use snapshot::{Error, ManifestData, Progress};

 use itertools::{Position, Itertools};
 use rlp::{RlpStream, Rlp};
@ -59,6 +59,7 @@ impl SnapshotComponents for PoaSnapshot {
 		chain: &BlockChain,
 		block_at: H256,
 		sink: &mut ChunkSink,
+		_progress: &Progress,
 		preferred_size: usize,
 	) -> Result<(), Error> {
 		let number = chain.block_number(&block_at)
--- a/ethcore/src/snapshot/consensus/mod.rs
+++ b/ethcore/src/snapshot/consensus/mod.rs
@ -22,7 +22,7 @@ use std::sync::Arc;

 use blockchain::{BlockChain, BlockChainDB};
 use engines::EthEngine;
-use snapshot::{Error, ManifestData};
+use snapshot::{Error, ManifestData, Progress};

 use ethereum_types::H256;

@ -49,6 +49,7 @@ pub trait SnapshotComponents: Send {
 		chain: &BlockChain,
 		block_at: H256,
 		chunk_sink: &mut ChunkSink,
+		progress: &Progress,
 		preferred_size: usize,
 	) -> Result<(), Error>;

--- a/ethcore/src/snapshot/consensus/work.rs
+++ b/ethcore/src/snapshot/consensus/work.rs
@ -28,7 +28,7 @@ use std::sync::Arc;

 use blockchain::{BlockChain, BlockChainDB, BlockProvider};
 use engines::EthEngine;
-use snapshot::{Error, ManifestData};
+use snapshot::{Error, ManifestData, Progress};
 use snapshot::block::AbridgedBlock;
 use ethereum_types::H256;
 use kvdb::KeyValueDB;
@ -65,6 +65,7 @@ impl SnapshotComponents for PowSnapshot {
 		chain: &BlockChain,
 		block_at: H256,
 		chunk_sink: &mut ChunkSink,
+		progress: &Progress,
 		preferred_size: usize,
 	) -> Result<(), Error> {
 		PowWorker {
@ -72,6 +73,7 @@ impl SnapshotComponents for PowSnapshot {
 			rlps: VecDeque::new(),
 			current_hash: block_at,
 			writer: chunk_sink,
+			progress: progress,
 			preferred_size: preferred_size,
 		}.chunk_all(self.blocks)
 	}
@ -96,6 +98,7 @@ struct PowWorker<'a> {
 	rlps: VecDeque<Bytes>,
 	current_hash: H256,
 	writer: &'a mut ChunkSink<'a>,
+	progress: &'a Progress,
 	preferred_size: usize,
 }

@ -138,6 +141,7 @@ impl<'a> PowWorker<'a> {

 			last = self.current_hash;
 			self.current_hash = block.header_view().parent_hash();
+			self.progress.blocks.fetch_add(1, Ordering::SeqCst);
 		}

 		if loaded_size != 0 {
--- a/ethcore/src/snapshot/mod.rs
+++ b/ethcore/src/snapshot/mod.rs
@ -20,6 +20,7 @@
 //! https://wiki.parity.io/Warp-Sync-Snapshot-Format

 use std::collections::{HashMap, HashSet};
+use std::cmp;
 use std::sync::Arc;
 use std::sync::atomic::{AtomicBool, AtomicUsize, Ordering};
 use hash::{keccak, KECCAK_NULL_RLP, KECCAK_EMPTY};
@ -43,6 +44,7 @@ use trie::{Trie, TrieMut};
 use ethtrie::{TrieDB, TrieDBMut};
 use rlp::{RlpStream, Rlp};
 use bloom_journal::Bloom;
+use num_cpus;

 use self::io::SnapshotWriter;

@ -88,6 +90,28 @@ const MAX_CHUNK_SIZE: usize = PREFERRED_CHUNK_SIZE / 4 * 5;
 const MIN_SUPPORTED_STATE_CHUNK_VERSION: u64 = 1;
 // current state chunk version.
 const STATE_CHUNK_VERSION: u64 = 2;
+/// number of snapshot subparts, must be a power of 2 in [1; 256]
+const SNAPSHOT_SUBPARTS: usize = 16;
+/// Maximum number of snapshot subparts (must be a multiple of `SNAPSHOT_SUBPARTS`)
+const MAX_SNAPSHOT_SUBPARTS: usize = 256;
+
+/// Configuration for the Snapshot service
+#[derive(Debug, Clone, PartialEq)]
+pub struct SnapshotConfiguration {
+	/// If `true`, no periodic snapshots will be created
+	pub no_periodic: bool,
+	/// Number of threads for creating snapshots
+	pub processing_threads: usize,
+}
+
+impl Default for SnapshotConfiguration {
+	fn default() -> Self {
+		SnapshotConfiguration {
+			no_periodic: false,
+			processing_threads: ::std::cmp::max(1, num_cpus::get() / 2),
+		}
+	}
+}

 /// A progress indicator for snapshots.
 #[derive(Debug, Default)]
@ -130,7 +154,8 @@ pub fn take_snapshot<W: SnapshotWriter + Send>(
 	block_at: H256,
 	state_db: &HashDB<KeccakHasher>,
 	writer: W,
-	p: &Progress
+	p: &Progress,
+	processing_threads: usize,
 ) -> Result<(), Error> {
 	let start_header = chain.block_header_data(&block_at)
 		.ok_or(Error::InvalidStartingBlock(BlockId::Hash(block_at)))?;
@ -142,17 +167,45 @@ pub fn take_snapshot<W: SnapshotWriter + Send>(
 	let writer = Mutex::new(writer);
 	let chunker = engine.snapshot_components().ok_or(Error::SnapshotsUnsupported)?;
 	let snapshot_version = chunker.current_version();
-	let (state_hashes, block_hashes) = scope(|scope| {
+	let (state_hashes, block_hashes) = scope(|scope| -> Result<(Vec<H256>, Vec<H256>), Error> {
 		let writer = &writer;
 		let block_guard = scope.spawn(move || chunk_secondary(chunker, chain, block_at, writer, p));
-		let state_res = chunk_state(state_db, &state_root, writer, p);

-		state_res.and_then(|state_hashes| {
-			block_guard.join().map(|block_hashes| (state_hashes, block_hashes))
-		})
+		// The number of threads must be between 1 and SNAPSHOT_SUBPARTS
+		assert!(processing_threads >= 1, "Cannot use less than 1 threads for creating snapshots");
+		let num_threads: usize = cmp::min(processing_threads, SNAPSHOT_SUBPARTS);
+		info!(target: "snapshot", "Using {} threads for Snapshot creation.", num_threads);
+
+		let mut state_guards = Vec::with_capacity(num_threads as usize);
+
+		for thread_idx in 0..num_threads {
+			let state_guard = scope.spawn(move || -> Result<Vec<H256>, Error> {
+				let mut chunk_hashes = Vec::new();
+
+				for part in (thread_idx..SNAPSHOT_SUBPARTS).step_by(num_threads) {
+					debug!(target: "snapshot", "Chunking part {} in thread {}", part, thread_idx);
+					let mut hashes = chunk_state(state_db, &state_root, writer, p, Some(part))?;
+					chunk_hashes.append(&mut hashes);
+				}
+
+				Ok(chunk_hashes)
+			});
+			state_guards.push(state_guard);
+		}
+
+		let block_hashes = block_guard.join()?;
+		let mut state_hashes = Vec::new();
+
+		for guard in state_guards {
+			let part_state_hashes = guard.join()?;
+			state_hashes.extend(part_state_hashes);
+		}
+
+		debug!(target: "snapshot", "Took a snapshot of {} accounts", p.accounts.load(Ordering::SeqCst));
+		Ok((state_hashes, block_hashes))
 	})?;

-	info!("produced {} state chunks and {} block chunks.", state_hashes.len(), block_hashes.len());
+	info!(target: "snapshot", "produced {} state chunks and {} block chunks.", state_hashes.len(), block_hashes.len());

 	let manifest_data = ManifestData {
 		version: snapshot_version,
@ -200,6 +253,7 @@ pub fn chunk_secondary<'a>(mut chunker: Box<SnapshotComponents>, chain: &'a Bloc
 			chain,
 			start_hash,
 			&mut chunk_sink,
+			progress,
 			PREFERRED_CHUNK_SIZE,
 		)?;
 	}
@ -263,10 +317,12 @@ impl<'a> StateChunker<'a> {

 /// Walk the given state database starting from the given root,
 /// creating chunks and writing them out.
+/// `part` is a number between 0 and 15, which describe which part of
+/// the tree should be chunked.
 ///
 /// Returns a list of hashes of chunks created, or any error it may
 /// have encountered.
-pub fn chunk_state<'a>(db: &HashDB<KeccakHasher>, root: &H256, writer: &Mutex<SnapshotWriter + 'a>, progress: &'a Progress) -> Result<Vec<H256>, Error> {
+pub fn chunk_state<'a>(db: &HashDB<KeccakHasher>, root: &H256, writer: &Mutex<SnapshotWriter + 'a>, progress: &'a Progress, part: Option<usize>) -> Result<Vec<H256>, Error> {
 	let account_trie = TrieDB::new(db, &root)?;

 	let mut chunker = StateChunker {
@ -281,11 +337,33 @@ pub fn chunk_state<'a>(db: &HashDB<KeccakHasher>, root: &H256, writer: &Mutex<Sn
 	let mut used_code = HashSet::new();

 	// account_key here is the address' hash.
-	for item in account_trie.iter()? {
+	let mut account_iter = account_trie.iter()?;
+
+	let mut seek_to = None;
+
+	if let Some(part) = part {
+		assert!(part < 16, "Wrong chunk state part number (must be <16) in snapshot creation.");
+
+		let part_offset = MAX_SNAPSHOT_SUBPARTS / SNAPSHOT_SUBPARTS;
+		let mut seek_from = vec![0; 32];
+		seek_from[0] = (part * part_offset) as u8;
+		account_iter.seek(&seek_from)?;
+
+		// Set the upper-bound, except for the last part
+		if part < SNAPSHOT_SUBPARTS - 1 {
+			seek_to = Some(((part + 1) * part_offset) as u8)
+		}
+	}
+
+	for item in account_iter {
 		let (account_key, account_data) = item?;
-		let account = ::rlp::decode(&*account_data)?;
 		let account_key_hash = H256::from_slice(&account_key);

+		if seek_to.map_or(false, |seek_to| account_key[0] >= seek_to) {
+			break;
+		}
+
+		let account = ::rlp::decode(&*account_data)?;
 		let account_db = AccountDB::from_hash(db, account_key_hash);

 		let fat_rlps = account::to_fat_rlps(&account_key_hash, &account, &account_db, &mut used_code, PREFERRED_CHUNK_SIZE - chunker.chunk_size(), PREFERRED_CHUNK_SIZE)?;
--- a/ethcore/src/snapshot/tests/state.rs
+++ b/ethcore/src/snapshot/tests/state.rs
@ -22,7 +22,7 @@ use hash::{KECCAK_NULL_RLP, keccak};

 use basic_account::BasicAccount;
 use snapshot::account;
-use snapshot::{chunk_state, Error as SnapshotError, Progress, StateRebuilder};
+use snapshot::{chunk_state, Error as SnapshotError, Progress, StateRebuilder, SNAPSHOT_SUBPARTS};
 use snapshot::io::{PackedReader, PackedWriter, SnapshotReader, SnapshotWriter};
 use super::helpers::{compare_dbs, StateProducer};

@ -53,7 +53,11 @@ fn snap_and_restore() {
 	let state_root = producer.state_root();
 	let writer = Mutex::new(PackedWriter::new(&snap_file).unwrap());

-	let state_hashes = chunk_state(&old_db, &state_root, &writer, &Progress::default()).unwrap();
+	let mut state_hashes = Vec::new();
+	for part in 0..SNAPSHOT_SUBPARTS {
+		let mut hashes = chunk_state(&old_db, &state_root, &writer, &Progress::default(), Some(part)).unwrap();
+		state_hashes.append(&mut hashes);
+	}

 	writer.into_inner().finish(::snapshot::ManifestData {
 		version: 2,
@ -164,7 +168,7 @@ fn checks_flag() {
 	let state_root = producer.state_root();
 	let writer = Mutex::new(PackedWriter::new(&snap_file).unwrap());

-	let state_hashes = chunk_state(&old_db, &state_root, &writer, &Progress::default()).unwrap();
+	let state_hashes = chunk_state(&old_db, &state_root, &writer, &Progress::default(), None).unwrap();

 	writer.into_inner().finish(::snapshot::ManifestData {
 		version: 2,
--- a/ethcore/src/tests/evm.rs
+++ b/ethcore/src/tests/evm.rs
@ -38,7 +38,7 @@ fn test_blockhash_eip210(factory: Factory) {
 	let test_blockhash_contract = "73fffffffffffffffffffffffffffffffffffffffe33141561007a57600143036020526000356101006020510755600061010060205107141561005057600035610100610100602051050761010001555b6000620100006020510714156100755760003561010062010000602051050761020001555b61014a565b4360003512151561009057600060405260206040f35b610100600035430312156100b357610100600035075460605260206060f3610149565b62010000600035430312156100d157600061010060003507146100d4565b60005b156100f6576101006101006000350507610100015460805260206080f3610148565b630100000060003543031215610116576000620100006000350714610119565b60005b1561013c57610100620100006000350507610200015460a052602060a0f3610147565b600060c052602060c0f35b5b5b5b5b";
 	let blockhash_contract_code = Arc::new(test_blockhash_contract.from_hex().unwrap());
 	let blockhash_contract_code_hash = keccak(blockhash_contract_code.as_ref());
-	let machine = ::ethereum::new_constantinople_test_machine();
+	let machine = ::ethereum::new_eip210_test_machine();
 	let mut env_info = EnvInfo::default();

 	// populate state with 256 last hashes
--- a/ethcore/sync/src/chain/propagator.rs
+++ b/ethcore/sync/src/chain/propagator.rs
@ -200,7 +200,7 @@ impl SyncPropagator {
 								let appended = packet.append_raw_checked(&transaction.drain(), 1, MAX_TRANSACTION_PACKET_SIZE);
 								if !appended {
 									// Maximal packet size reached just proceed with sending
-									debug!("Transaction packet size limit reached. Sending incomplete set of {}/{} transactions.", pushed, to_send.len());
+									debug!(target: "sync", "Transaction packet size limit reached. Sending incomplete set of {}/{} transactions.", pushed, to_send.len());
 									to_send = to_send.into_iter().take(pushed).collect();
 									break;
 								}
--- a/ethcore/vm/Cargo.toml
+++ b/ethcore/vm/Cargo.toml
@ -7,7 +7,7 @@ authors = ["Parity Technologies <admin@parity.io>"]
 byteorder = "1.0"
 parity-bytes = "0.1"
 ethereum-types = "0.4"
-patricia-trie = "0.2.1"
+patricia-trie = "0.2"
 patricia-trie-ethereum = { path = "../../util/patricia-trie-ethereum" }
 log = "0.4"
 common-types = { path = "../types" }
--- a/parity/cli/mod.rs
+++ b/parity/cli/mod.rs
@ -704,11 +704,11 @@ usage! {
 			"--price-update-period=[T]",
 			"T will be allowed to pass between each gas price update. T may be daily, hourly, a number of seconds, or a time string of the form \"2 days\", \"30 minutes\" etc..",

-			ARG arg_gas_floor_target: (String) = "4700000", or |c: &Config| c.mining.as_ref()?.gas_floor_target.clone(),
+			ARG arg_gas_floor_target: (String) = "8000000", or |c: &Config| c.mining.as_ref()?.gas_floor_target.clone(),
 			"--gas-floor-target=[GAS]",
 			"Amount of gas per block to target when sealing a new block.",

-			ARG arg_gas_cap: (String) = "6283184", or |c: &Config| c.mining.as_ref()?.gas_cap.clone(),
+			ARG arg_gas_cap: (String) = "10000000", or |c: &Config| c.mining.as_ref()?.gas_cap.clone(),
 			"--gas-cap=[GAS]",
 			"A cap on how large we will raise the gas limit per block due to transaction volume.",

@ -865,6 +865,10 @@ usage! {
 			"--no-periodic-snapshot",
 			"Disable automated snapshots which usually occur once every 10000 blocks.",

+			ARG arg_snapshot_threads: (Option<usize>) = None, or |c: &Config| c.snapshots.as_ref()?.processing_threads,
+			"--snapshot-threads=[NUM]",
+			"Enables multiple threads for snapshots creation.",
+
 		["Whisper Options"]
 			FLAG flag_whisper: (bool) = false, or |c: &Config| c.whisper.as_ref()?.enabled,
 			"--whisper",
@ -1345,6 +1349,7 @@ struct Footprint {
 #[serde(deny_unknown_fields)]
 struct Snapshots {
 	disable_periodic: Option<bool>,
+	processing_threads: Option<usize>,
 }

 #[derive(Default, Debug, PartialEq, Deserialize)]
@ -1712,7 +1717,7 @@ mod tests {
 			arg_reseal_max_period: 60000u64,
 			flag_reseal_on_uncle: false,
 			arg_work_queue_size: 20usize,
-			arg_tx_gas_limit: Some("6283184".into()),
+			arg_tx_gas_limit: Some("10000000".into()),
 			arg_tx_time_limit: Some(100u64),
 			arg_relay_set: "cheap".into(),
 			arg_min_gas_price: Some(0u64),
@ -1721,8 +1726,8 @@ mod tests {
 			arg_poll_lifetime: 60u32,
 			arg_usd_per_eth: "auto".into(),
 			arg_price_update_period: "hourly".into(),
-			arg_gas_floor_target: "4700000".into(),
-			arg_gas_cap: "6283184".into(),
+			arg_gas_floor_target: "8000000".into(),
+			arg_gas_cap: "10000000".into(),
 			arg_extra_data: Some("Parity".into()),
 			flag_tx_queue_no_unfamiliar_locals: false,
 			flag_tx_queue_no_early_reject: false,
@ -1771,6 +1776,7 @@ mod tests {
 			arg_export_state_at: "latest".into(),
 			arg_snapshot_at: "latest".into(),
 			flag_no_periodic_snapshot: false,
+			arg_snapshot_threads: None,

 			// -- Whisper options.
 			flag_whisper: false,
@ -2021,6 +2027,7 @@ mod tests {
 			}),
 			snapshots: Some(Snapshots {
 				disable_periodic: Some(true),
+				processing_threads: None,
 			}),
 			misc: Some(Misc {
 				logging: Some("own_tx=trace".into()),
--- a/parity/cli/tests/config.full.toml
+++ b/parity/cli/tests/config.full.toml
@ -125,13 +125,13 @@ min_gas_price = 0
 usd_per_tx = "0.0001"
 usd_per_eth = "auto"
 price_update_period = "hourly"
-gas_floor_target = "4700000"
-gas_cap = "6283184"
+gas_floor_target = "8000000"
+gas_cap = "10000000"
 tx_queue_size = 8192
 tx_queue_strategy = "gas_factor"
 tx_queue_ban_count = 1
 tx_queue_ban_time = 180 #s
-tx_gas_limit = "6283184"
+tx_gas_limit = "10000000"
 tx_time_limit = 100 #ms
 tx_queue_no_unfamiliar_locals = false
 tx_queue_no_early_reject = false
--- a/parity/configuration.rs
+++ b/parity/configuration.rs
@ -30,8 +30,10 @@ use sync::{NetworkConfiguration, validate_node_url, self};
 use ethcore::ethstore::ethkey::{Secret, Public};
 use ethcore::client::{VMType};
 use ethcore::miner::{stratum, MinerOptions};
+use ethcore::snapshot::SnapshotConfiguration;
 use ethcore::verification::queue::VerifierSettings;
 use miner::pool;
+use num_cpus;

 use rpc::{IpcConfiguration, HttpConfiguration, WsConfiguration};
 use parity_rpc::NetworkSettings;
@ -125,6 +127,7 @@ impl Configuration {
 		let update_policy = self.update_policy()?;
 		let logger_config = self.logger_config();
 		let ws_conf = self.ws_config()?;
+		let snapshot_conf = self.snapshot_config()?;
 		let http_conf = self.http_config()?;
 		let ipc_conf = self.ipc_config()?;
 		let net_conf = self.net_config()?;
@ -298,6 +301,7 @@ impl Configuration {
 				file_path: self.args.arg_snapshot_file.clone(),
 				kind: snapshot::Kind::Take,
 				block_at: to_block_id(&self.args.arg_snapshot_at)?,
+				snapshot_conf: snapshot_conf,
 			};
 			Cmd::Snapshot(snapshot_cmd)
 		} else if self.args.cmd_restore {
@ -314,6 +318,7 @@ impl Configuration {
 				file_path: self.args.arg_restore_file.clone(),
 				kind: snapshot::Kind::Restore,
 				block_at: to_block_id("latest")?, // unimportant.
+				snapshot_conf: snapshot_conf,
 			};
 			Cmd::Snapshot(restore_cmd)
 		} else if self.args.cmd_export_hardcoded_sync {
@ -349,6 +354,7 @@ impl Configuration {
 				gas_price_percentile: self.args.arg_gas_price_percentile,
 				poll_lifetime: self.args.arg_poll_lifetime,
 				ws_conf: ws_conf,
+				snapshot_conf: snapshot_conf,
 				http_conf: http_conf,
 				ipc_conf: ipc_conf,
 				net_conf: net_conf,
@ -374,7 +380,6 @@ impl Configuration {
 				private_tx_enabled,
 				name: self.args.arg_identity,
 				custom_bootnodes: self.args.arg_bootnodes.is_some(),
-				no_periodic_snapshot: self.args.flag_no_periodic_snapshot,
 				check_seal: !self.args.flag_no_seal_check,
 				download_old_blocks: !self.args.flag_no_ancient_blocks,
 				verifier_settings: verifier_settings,
@ -890,6 +895,18 @@ impl Configuration {
 		Ok((provider_conf, encryptor_conf, self.args.flag_private_enabled))
 	}

+	fn snapshot_config(&self) -> Result<SnapshotConfiguration, String> {
+		let conf = SnapshotConfiguration {
+			no_periodic: self.args.flag_no_periodic_snapshot,
+			processing_threads: match self.args.arg_snapshot_threads {
+				Some(threads) if threads > 0 => threads,
+				_ => ::std::cmp::max(1, num_cpus::get() / 2),
+			},
+		};
+
+		Ok(conf)
+	}
+
 	fn network_settings(&self) -> Result<NetworkSettings, String> {
 		let http_conf = self.http_config()?;
 		let net_addresses = self.net_addresses()?;
@ -1398,7 +1415,7 @@ mod tests {
 			name: "".into(),
 			custom_bootnodes: false,
 			fat_db: Default::default(),
-			no_periodic_snapshot: false,
+			snapshot_conf: Default::default(),
 			stratum: None,
 			check_seal: true,
 			download_old_blocks: true,
--- a/parity/params.rs
+++ b/parity/params.rs
@ -286,7 +286,7 @@ impl Default for MinerExtras {
 			author: Default::default(),
 			engine_signer: Default::default(),
 			extra_data: version_data(),
-			gas_range_target: (4_700_000.into(), 6_283_184.into()),
+			gas_range_target: (8_000_000.into(), 10_000_000.into()),
 			work_notify: Default::default(),
 		}
 	}
--- a/parity/run.rs
+++ b/parity/run.rs
@ -25,7 +25,7 @@ use ethcore::account_provider::{AccountProvider, AccountProviderSettings};
 use ethcore::client::{BlockId, CallContract, Client, Mode, DatabaseCompactionProfile, VMType, BlockChainClient, BlockInfo};
 use ethcore::ethstore::ethkey;
 use ethcore::miner::{stratum, Miner, MinerService, MinerOptions};
-use ethcore::snapshot;
+use ethcore::snapshot::{self, SnapshotConfiguration};
 use ethcore::spec::{SpecParams, OptimizeFor};
 use ethcore::verification::queue::VerifierSettings;
 use ethcore_logger::{Config as LogConfig, RotatingLogger};
@ -119,7 +119,7 @@ pub struct RunCmd {
 	pub name: String,
 	pub custom_bootnodes: bool,
 	pub stratum: Option<stratum::Options>,
-	pub no_periodic_snapshot: bool,
+	pub snapshot_conf: SnapshotConfiguration,
 	pub check_seal: bool,
 	pub download_old_blocks: bool,
 	pub verifier_settings: VerifierSettings,
@ -531,6 +531,7 @@ fn execute_impl<Cr, Rr>(cmd: RunCmd, logger: Arc<RotatingLogger>, on_client_rq:

 	client_config.queue.verifier_settings = cmd.verifier_settings;
 	client_config.transaction_verification_queue_size = ::std::cmp::max(2048, txpool_size / 4);
+	client_config.snapshot = cmd.snapshot_conf.clone();

 	// set up bootnodes
 	let mut net_conf = cmd.net_conf;
@ -778,7 +779,7 @@ fn execute_impl<Cr, Rr>(cmd: RunCmd, logger: Arc<RotatingLogger>, on_client_rq:
 	});

 	// the watcher must be kept alive.
-	let watcher = match cmd.no_periodic_snapshot {
+	let watcher = match cmd.snapshot_conf.no_periodic {
 		true => None,
 		false => {
 			let sync = sync_provider.clone();
--- a/parity/snapshot.rs
+++ b/parity/snapshot.rs
@ -22,7 +22,7 @@ use std::sync::Arc;

 use hash::keccak;
 use ethcore::account_provider::AccountProvider;
-use ethcore::snapshot::{Progress, RestorationStatus, SnapshotService as SS};
+use ethcore::snapshot::{Progress, RestorationStatus, SnapshotConfiguration, SnapshotService as SS};
 use ethcore::snapshot::io::{SnapshotReader, PackedReader, PackedWriter};
 use ethcore::snapshot::service::Service as SnapshotService;
 use ethcore::client::{Mode, DatabaseCompactionProfile, VMType};
@ -62,6 +62,7 @@ pub struct SnapshotCommand {
 	pub file_path: Option<String>,
 	pub kind: Kind,
 	pub block_at: BlockId,
+	pub snapshot_conf: SnapshotConfiguration,
 }

 // helper for reading chunks from arbitrary reader and feeding them into the
@ -165,7 +166,7 @@ impl SnapshotCommand {
 		execute_upgrades(&self.dirs.base, &db_dirs, algorithm, &self.compaction)?;

 		// prepare client config
-		let client_config = to_client_config(
+		let mut client_config = to_client_config(
 			&self.cache_config,
 			spec.name.to_lowercase(),
 			Mode::Active,
@ -180,6 +181,8 @@ impl SnapshotCommand {
 			true,
 		);

+		client_config.snapshot = self.snapshot_conf;
+
 		let restoration_db_handler = db::restoration_db_handler(&client_path, &client_config);
 		let client_db = restoration_db_handler.open(&client_path)
 			.map_err(|e| format!("Failed to open database {:?}", e))?;
--- a/rpc/Cargo.toml
+++ b/rpc/Cargo.toml
@ -58,7 +58,7 @@ keccak-hash = "0.1.2"
 parity-reactor = { path = "../util/reactor" }
 parity-updater = { path = "../updater" }
 parity-version = { path = "../util/version" }
-patricia-trie = "0.2.1"
+patricia-trie = "0.2"
 rlp = { version = "0.2.4", features = ["ethereum"] }
 stats = { path = "../util/stats" }
 vm = { path = "../ethcore/vm" }
--- a/rpc/src/authcodes.rs
+++ b/rpc/src/authcodes.rs
@ -50,8 +50,6 @@ impl TimeProvider for DefaultTimeProvider {
 const TIME_THRESHOLD: u64 = 7;
 /// minimal length of hash
 const TOKEN_LENGTH: usize = 16;
-/// special "initial" token used for authorization when there are no tokens yet.
-const INITIAL_TOKEN: &'static str = "initial";
 /// Separator between fields in serialized tokens file.
 const SEPARATOR: &'static str = ";";
 /// Number of seconds to keep unused tokens.
@ -163,16 +161,6 @@ impl<T: TimeProvider> AuthCodes<T> {

 		let as_token = |code| keccak(format!("{}:{}", code, time));

-		// Check if it's the initial token.
-		if self.is_empty() {
-			let initial = &as_token(INITIAL_TOKEN) == hash;
-			// Initial token can be used only once.
-			if initial {
-				let _ = self.generate_new();
-			}
-			return initial;
-		}
-
 		// look for code
 		for code in &mut self.codes {
 			if &as_token(&code.code) == hash {
@ -239,7 +227,7 @@ mod tests {
 	}

 	#[test]
-	fn should_return_true_if_code_is_initial_and_store_is_empty() {
+	fn should_return_false_even_if_code_is_initial_and_store_is_empty() {
 		// given
 		let code = "initial";
 		let time = 99;
@ -250,7 +238,7 @@ mod tests {
 		let res2 = codes.is_valid(&generate_hash(code, time), time);

 		// then
-		assert_eq!(res1, true);
+		assert_eq!(res1, false);
 		assert_eq!(res2, false);
 	}

--- a/rpc/src/tests/ws.rs
+++ b/rpc/src/tests/ws.rs
@ -136,7 +136,7 @@ mod testing {
 	}

 	#[test]
-	fn should_allow_initial_connection_but_only_once() {
+	fn should_not_allow_initial_connection_even_once() {
 		// given
 		let (server, port, authcodes) = serve();
 		let code = "initial";
@ -160,26 +160,9 @@ mod testing {
 			timestamp,
 			)
 		);
-		let response2 = http_client::request(server.addr(),
-			&format!("\
-				GET / HTTP/1.1\r\n\
-				Host: 127.0.0.1:{}\r\n\
-				Connection: Close\r\n\
-				Sec-WebSocket-Key: x3JJHMbDL1EzLkh9GBhXDw==\r\n\
-				Sec-WebSocket-Protocol:{:?}_{}\r\n\
-				Sec-WebSocket-Version: 13\r\n\
-				\r\n\
-				{{}}
-			",
-			port,
-			keccak(format!("{}:{}", code, timestamp)),
-			timestamp,
-			)
-		);

 		// then
-		assert_eq!(response1.status, "HTTP/1.1 101 Switching Protocols".to_owned());
-		assert_eq!(response2.status, "HTTP/1.1 403 Forbidden".to_owned());
-		http_client::assert_security_headers_present(&response2.headers, None);
+		assert_eq!(response1.status, "HTTP/1.1 403 Forbidden".to_owned());
+		http_client::assert_security_headers_present(&response1.headers, None);
 	}
 }
--- a/rpc/src/v1/impls/net.rs
+++ b/rpc/src/v1/impls/net.rs
@ -22,7 +22,12 @@ use v1::traits::Net;

 /// Net rpc implementation.
 pub struct NetClient<S: ?Sized> {
-	sync: Arc<S>
+	sync: Arc<S>,
+	/// Cached `network_id`.
+	///
+	/// We cache it to avoid redundant aquire of sync read lock.
+	/// https://github.com/paritytech/parity-ethereum/issues/8746
+	network_id: u64,
 }

 impl<S: ?Sized> NetClient<S> where S: SyncProvider {
@ -30,17 +35,18 @@ impl<S: ?Sized> NetClient<S> where S: SyncProvider {
 	pub fn new(sync: &Arc<S>) -> Self {
 		NetClient {
 			sync: sync.clone(),
+			network_id: sync.status().network_id,
 		}
 	}
 }

 impl<S: ?Sized> Net for NetClient<S> where S: SyncProvider + 'static {
 	fn version(&self) -> Result<String> {
-		Ok(format!("{}", self.sync.status().network_id).to_owned())
+		Ok(format!("{}", self.network_id))
 	}

 	fn peer_count(&self) -> Result<String> {
-		Ok(format!("0x{:x}", self.sync.status().num_peers as u64).to_owned())
+		Ok(format!("{:#x}", self.sync.status().num_peers as u64))
 	}

 	fn is_listening(&self) -> Result<bool> {
--- a/scripts/gitlab/package-snap.sh
+++ b/scripts/gitlab/package-snap.sh
@ -3,9 +3,9 @@
 set -e # fail on any error
 set -u # treat unset variables as error
 case ${CI_COMMIT_REF_NAME} in
-  nightly|*v2.1*) export GRADE="devel";;
-  beta|*v2.0*) export GRADE="stable";;
-  stable|*v1.11*) export GRADE="stable";;
+  nightly|*v2.2*) export GRADE="devel";;
+  beta|*v2.1*) export GRADE="stable";;
+  stable|*v2.0*) export GRADE="stable";;
  *) echo "No release" exit 0;;
 esac
 SNAP_PACKAGE="parity_"$VERSION"_"$BUILD_ARCH".snap"
--- a/scripts/gitlab/publish-docker.sh
+++ b/scripts/gitlab/publish-docker.sh
@ -3,7 +3,7 @@
 set -e # fail on any error
 set -u # treat unset variables as error

-if [ "$CI_COMMIT_REF_NAME" == "beta" ];
+if [ "$CI_COMMIT_REF_NAME" == "master" ];
 then export DOCKER_BUILD_TAG="latest";
 else export DOCKER_BUILD_TAG=$CI_COMMIT_REF_NAME;
 fi
--- a/scripts/gitlab/publish-snap.sh
+++ b/scripts/gitlab/publish-snap.sh
@ -4,9 +4,9 @@ set -e # fail on any error
 set -u # treat unset variables as error

 case ${CI_COMMIT_REF_NAME} in
-  nightly|*v2.1*) export CHANNEL="edge";;
-  beta|*v2.0*) export CHANNEL="beta";;
-  stable|*v1.11*) export CHANNEL="stable";;
+  nightly|*v2.2*) export CHANNEL="edge";;
+  beta|*v2.1*) export CHANNEL="beta";;
+  stable|*v2.0*) export CHANNEL="stable";;
  *) echo "No release" exit 0;;
 esac
 echo "Release channel :" $CHANNEL " Branch/tag: " $CI_COMMIT_REF_NAME
--- a/scripts/gitlab/push.sh
+++ b/scripts/gitlab/push.sh
@ -14,9 +14,9 @@ RELEASE_TABLE="$(echo "${RELEASE_TABLE//\$VERSION/${VERSION}}")"
 #The text in the file CANGELOG.md before which the table with links is inserted. Must be present in this file necessarily
 REPLACE_TEXT="The full list of included changes:"
 case ${CI_COMMIT_REF_NAME} in
-  nightly|*v2.1*) NAME="Parity "$VERSION" nightly";;
-  beta|*v2.0*) NAME="Parity "$VERSION" beta";;
-  stable|*v1.11*) NAME="Parity "$VERSION" stable";;
+  nightly|*v2.2*) NAME="Parity "$VERSION" nightly";;
+  beta|*v2.1*) NAME="Parity "$VERSION" beta";;
+  stable|*v2.0*) NAME="Parity "$VERSION" stable";;
  *) echo "No release" exit 0;;
 esac
 cd artifacts
--- a/scripts/gitlab/rpc-docs.sh
+++ b/scripts/gitlab/rpc-docs.sh
@ -42,12 +42,12 @@ upload_files() {
    git push --tags
 }

-RPC_TRAITS_DIR="rpc/src/v1/traits/"
+RPC_TRAITS_DIR="rpc/src/v1/traits"

 setup_git
 clone_repos
 mkdir -p "jsonrpc/.parity/$RPC_TRAITS_DIR"
-cp -r "$RPC_TRAITS_DIR" "jsonrpc/.parity/$RPC_TRAITS_DIR"
+cp $RPC_TRAITS_DIR/*.rs "jsonrpc/.parity/$RPC_TRAITS_DIR"
 cd jsonrpc
 build_docs
 cd ..
--- a/util/network-devp2p/src/discovery.rs
+++ b/util/network-devp2p/src/discovery.rs
@ -42,9 +42,9 @@ const PACKET_PONG: u8 = 2;
 const PACKET_FIND_NODE: u8 = 3;
 const PACKET_NEIGHBOURS: u8 = 4;

-const PING_TIMEOUT: Duration = Duration::from_millis(300);
+const PING_TIMEOUT: Duration = Duration::from_millis(500);
 const FIND_NODE_TIMEOUT: Duration = Duration::from_secs(2);
-const EXPIRY_TIME: Duration = Duration::from_secs(60);
+const EXPIRY_TIME: Duration = Duration::from_secs(20);
 const MAX_NODES_PING: usize = 32; // Max nodes to add/ping at once
 const REQUEST_BACKOFF: [Duration; 4] = [
 	Duration::from_secs(1),
@ -80,15 +80,29 @@ impl BucketEntry {
 	}
 }

-pub struct NodeBucket {
-	nodes: VecDeque<BucketEntry>, //sorted by last active
+struct FindNodeRequest {
+	// Time when the request was sent
+	sent_at: Instant,
+	// Number of items sent by the node
+	response_count: usize,
+	// Whether the request have been answered yet
+	answered: bool,
 }

-struct PendingRequest {
-	packet_id: u8,
+struct PingRequest {
+	// Time when the request was sent
 	sent_at: Instant,
-	packet_hash: H256,
-	response_count: usize, // Some requests (eg. FIND_NODE) have multi-packet responses
+	// The node to which the request was sent
+	node: NodeEntry,
+	// The hash sent in the Ping request
+	echo_hash: H256,
+	// The hash Parity used to respond with (until rev 01f825b0e1f1c4c420197b51fc801cbe89284b29)
+	#[deprecated()]
+	deprecated_echo_hash: H256,
+}
+
+pub struct NodeBucket {
+	nodes: VecDeque<BucketEntry>, //sorted by last active
 }

 impl Default for NodeBucket {
@ -115,13 +129,13 @@ pub struct Discovery<'a> {
 	id_hash: H256,
 	secret: Secret,
 	public_endpoint: NodeEndpoint,
-	discovery_round: u16,
+	discovery_initiated: bool,
+	discovery_round: Option<u16>,
 	discovery_id: NodeId,
 	discovery_nodes: HashSet<NodeId>,
 	node_buckets: Vec<NodeBucket>,
-	in_flight_requests: HashMap<NodeId, PendingRequest>,
-	expiring_pings: VecDeque<(NodeId, Instant)>,
-	expiring_finds: VecDeque<(NodeId, Instant)>,
+	in_flight_pings: HashMap<NodeId, PingRequest>,
+	in_flight_find_nodes: HashMap<NodeId, FindNodeRequest>,
 	send_queue: VecDeque<Datagram>,
 	check_timestamps: bool,
 	adding_nodes: Vec<NodeEntry>,
@ -141,13 +155,13 @@ impl<'a> Discovery<'a> {
 			id_hash: keccak(key.public()),
 			secret: key.secret().clone(),
 			public_endpoint: public,
-			discovery_round: 0,
+			discovery_initiated: false,
+			discovery_round: None,
 			discovery_id: NodeId::new(),
 			discovery_nodes: HashSet::new(),
 			node_buckets: (0..ADDRESS_BITS).map(|_| NodeBucket::new()).collect(),
-			in_flight_requests: HashMap::new(),
-			expiring_pings: VecDeque::new(),
-			expiring_finds: VecDeque::new(),
+			in_flight_pings: HashMap::new(),
+			in_flight_find_nodes: HashMap::new(),
 			send_queue: VecDeque::new(),
 			check_timestamps: true,
 			adding_nodes: Vec::new(),
@ -175,15 +189,6 @@ impl<'a> Discovery<'a> {
 		}
 	}

-	/// Add a list of known nodes to the table.
-	pub fn init_node_list(&mut self, nodes: Vec<NodeEntry>) {
-		for n in nodes {
-			if self.is_allowed(&n) {
-				self.update_node(n);
-			}
-		}
-	}
-
 	fn update_node(&mut self, e: NodeEntry) -> Option<TableUpdates> {
 		trace!(target: "discovery", "Inserting {:?}", &e);
 		let id_hash = keccak(e.id);
@ -224,13 +229,20 @@ impl<'a> Discovery<'a> {
 	/// Starts the discovery process at round 0
 	fn start(&mut self) {
 		trace!(target: "discovery", "Starting discovery");
-		self.discovery_round = 0;
+		self.discovery_round = Some(0);
 		self.discovery_id.randomize(); //TODO: use cryptographic nonce
 		self.discovery_nodes.clear();
 	}

+	/// Complete the discovery process
+	fn stop(&mut self) {
+		trace!(target: "discovery", "Completing discovery");
+		self.discovery_round = None;
+		self.discovery_nodes.clear();
+	}
+
 	fn update_new_nodes(&mut self) {
-		while self.in_flight_requests.len() < MAX_NODES_PING {
+		while self.in_flight_pings.len() < MAX_NODES_PING {
 			match self.adding_nodes.pop() {
 				Some(next) => self.try_ping(next),
 				None => break,
@ -239,8 +251,12 @@ impl<'a> Discovery<'a> {
 	}

 	fn discover(&mut self) {
-		self.update_new_nodes();
-		if self.discovery_round == DISCOVERY_MAX_STEPS {
+		let discovery_round = match self.discovery_round {
+			Some(r) => r,
+			None => return,
+		};
+		if discovery_round == DISCOVERY_MAX_STEPS {
+			self.stop();
 			return;
 		}
 		trace!(target: "discovery", "Starting round {:?}", self.discovery_round);
@ -263,12 +279,10 @@ impl<'a> Discovery<'a> {
 		}

 		if tried_count == 0 {
-			trace!(target: "discovery", "Completing discovery");
-			self.discovery_round = DISCOVERY_MAX_STEPS;
-			self.discovery_nodes.clear();
+			self.stop();
 			return;
 		}
-		self.discovery_round += 1;
+		self.discovery_round = Some(discovery_round + 1);
 	}

 	/// The base 2 log of the distance between a and b using the XOR metric.
@ -285,14 +299,20 @@ impl<'a> Discovery<'a> {
 	}

 	fn try_ping(&mut self, node: NodeEntry) {
-		if !self.is_allowed(&node) ||
-			self.in_flight_requests.contains_key(&node.id) ||
-			self.adding_nodes.iter().any(|n| n.id == node.id)
-		{
+		if !self.is_allowed(&node) {
+			trace!(target: "discovery", "Node {:?} not allowed", node);
+			return;
+		}
+		if self.in_flight_pings.contains_key(&node.id) || self.in_flight_find_nodes.contains_key(&node.id) {
+			trace!(target: "discovery", "Node {:?} in flight requests", node);
+			return;
+		}
+		if self.adding_nodes.iter().any(|n| n.id == node.id) {
+			trace!(target: "discovery", "Node {:?} in adding nodes", node);
 			return;
 		}

-		if self.in_flight_requests.len() < MAX_NODES_PING {
+		if self.in_flight_pings.len() < MAX_NODES_PING {
 			self.ping(&node)
 				.unwrap_or_else(|e| {
 					warn!(target: "discovery", "Error sending Ping packet: {:?}", e);
@ -308,18 +328,17 @@ impl<'a> Discovery<'a> {
 		self.public_endpoint.to_rlp_list(&mut rlp);
 		node.endpoint.to_rlp_list(&mut rlp);
 		append_expiration(&mut rlp);
+		let old_parity_hash = keccak(rlp.as_raw());
 		let hash = self.send_packet(PACKET_PING, &node.endpoint.udp_address(), &rlp.drain())?;

-		let request_info = PendingRequest {
-			packet_id: PACKET_PING,
+		self.in_flight_pings.insert(node.id, PingRequest {
 			sent_at: Instant::now(),
-			packet_hash: hash,
-			response_count: 0,
-		};
-		self.expiring_pings.push_back((node.id, request_info.sent_at));
-		self.in_flight_requests.insert(node.id, request_info);
+			node: node.clone(),
+			echo_hash: hash,
+			deprecated_echo_hash: old_parity_hash,
+		});

-		trace!(target: "discovery", "Sent Ping to {:?}", &node.endpoint);
+		trace!(target: "discovery", "Sent Ping to {:?} ; node_id={:#x}", &node.endpoint, node.id);
 		Ok(())
 	}

@ -327,16 +346,13 @@ impl<'a> Discovery<'a> {
 		let mut rlp = RlpStream::new_list(2);
 		rlp.append(target);
 		append_expiration(&mut rlp);
-		let hash = self.send_packet(PACKET_FIND_NODE, &node.endpoint.udp_address(), &rlp.drain())?;
+		self.send_packet(PACKET_FIND_NODE, &node.endpoint.udp_address(), &rlp.drain())?;

-		let request_info = PendingRequest {
-			packet_id: PACKET_FIND_NODE,
+		self.in_flight_find_nodes.insert(node.id, FindNodeRequest {
 			sent_at: Instant::now(),
-			packet_hash: hash,
 			response_count: 0,
-		};
-		self.expiring_finds.push_back((node.id, request_info.sent_at));
-		self.in_flight_requests.insert(node.id, request_info);
+			answered: false,
+		});

 		trace!(target: "discovery", "Sent FindNode to {:?}", &node.endpoint);
 		Ok(())
@ -448,20 +464,31 @@ impl<'a> Discovery<'a> {
 		entry.endpoint.is_allowed(&self.ip_filter) && entry.id != self.id
 	}

-	fn on_ping(&mut self, rlp: &Rlp, node: &NodeId, from: &SocketAddr, echo_hash: &[u8]) -> Result<Option<TableUpdates>, Error> {
+	fn on_ping(&mut self, rlp: &Rlp, node_id: &NodeId, from: &SocketAddr, echo_hash: &[u8]) -> Result<Option<TableUpdates>, Error> {
 		trace!(target: "discovery", "Got Ping from {:?}", &from);
-		let source = NodeEndpoint::from_rlp(&rlp.at(1)?)?;
-		let dest = NodeEndpoint::from_rlp(&rlp.at(2)?)?;
+		let ping_from = NodeEndpoint::from_rlp(&rlp.at(1)?)?;
+		let ping_to = NodeEndpoint::from_rlp(&rlp.at(2)?)?;
 		let timestamp: u64 = rlp.val_at(3)?;
 		self.check_timestamp(timestamp)?;

 		let mut response = RlpStream::new_list(3);
-		dest.to_rlp_list(&mut response);
+		let pong_to = NodeEndpoint {
+			address: from.clone(),
+			udp_port: ping_from.udp_port
+		};
+		// Here the PONG's `To` field should be the node we are
+		// sending the request to
+		// WARNING: this field _should not be used_, but old Parity versions
+		// use it in order to get the node's address.
+		// So this is a temporary fix so that older Parity versions don't brake completely.
+		ping_to.to_rlp_list(&mut response);
+		// pong_to.to_rlp_list(&mut response);
+
 		response.append(&echo_hash);
 		append_expiration(&mut response);
 		self.send_packet(PACKET_PONG, from, &response.drain())?;

-		let entry = NodeEntry { id: *node, endpoint: source.clone() };
+		let entry = NodeEntry { id: *node_id, endpoint: pong_to.clone() };
 		if !entry.endpoint.is_valid() {
 			debug!(target: "discovery", "Got bad address: {:?}", entry);
 		} else if !self.is_allowed(&entry) {
@ -469,40 +496,45 @@ impl<'a> Discovery<'a> {
 		} else {
 			self.add_node(entry.clone());
 		}
-
 		Ok(None)
 	}

 	fn on_pong(&mut self, rlp: &Rlp, node_id: &NodeId, from: &SocketAddr) -> Result<Option<TableUpdates>, Error> {
-		trace!(target: "discovery", "Got Pong from {:?}", &from);
-		let dest = NodeEndpoint::from_rlp(&rlp.at(0)?)?;
+		trace!(target: "discovery", "Got Pong from {:?} ; node_id={:#x}", &from, node_id);
+		let _pong_to = NodeEndpoint::from_rlp(&rlp.at(0)?)?;
 		let echo_hash: H256 = rlp.val_at(1)?;
 		let timestamp: u64 = rlp.val_at(2)?;
 		self.check_timestamp(timestamp)?;
-		let mut node = NodeEntry { id: *node_id, endpoint: dest };
-		if !node.endpoint.is_valid() {
-			debug!(target: "discovery", "Bad address: {:?}", node);
-			node.endpoint.address = *from;
-		}

-		let is_expected = match self.in_flight_requests.entry(*node_id) {
+		let expected_node = match self.in_flight_pings.entry(*node_id) {
 			Entry::Occupied(entry) => {
-				let is_expected = {
+				let expected_node = {
 					let request = entry.get();
-					request.packet_id == PACKET_PING && request.packet_hash == echo_hash
+					if request.echo_hash != echo_hash && request.deprecated_echo_hash != echo_hash {
+						debug!(target: "discovery", "Got unexpected Pong from {:?} ; packet_hash={:#x} ; expected_hash={:#x}", &from, request.echo_hash, echo_hash);
+						None
+					} else {
+						if request.deprecated_echo_hash == echo_hash {
+							trace!(target: "discovery", "Got Pong from an old parity-ethereum version.");
+						}
+						Some(request.node.clone())
+					}
 				};
-				if is_expected {
+
+				if expected_node.is_some() {
 					entry.remove();
 				}
-				is_expected
+				expected_node
+			},
+			Entry::Vacant(_) => {
+				None
 			},
-			Entry::Vacant(_) => false
 		};

-		if is_expected {
+		if let Some(node) = expected_node {
 			Ok(self.update_node(node))
 		} else {
-			debug!(target: "discovery", "Got unexpected Pong from {:?}", &from);
+			debug!(target: "discovery", "Got unexpected Pong from {:?} ; request not found", &from);
 			Ok(None)
 		}
 	}
@ -544,29 +576,32 @@ impl<'a> Discovery<'a> {
 	fn on_neighbours(&mut self, rlp: &Rlp, node_id: &NodeId, from: &SocketAddr) -> Result<Option<TableUpdates>, Error> {
 		let results_count = rlp.at(0)?.item_count()?;

-		let is_expected = match self.in_flight_requests.entry(*node_id) {
+		let is_expected = match self.in_flight_find_nodes.entry(*node_id) {
 			Entry::Occupied(mut entry) => {
-				let result = {
+				let expected = {
 					let request = entry.get_mut();
-					if request.packet_id == PACKET_FIND_NODE &&
-						request.response_count + results_count <= BUCKET_SIZE
-					{
+					// Mark the request as answered
+					request.answered = true;
+					if request.response_count + results_count <= BUCKET_SIZE {
 						request.response_count += results_count;
 						true
 					} else {
+						debug!(target: "discovery", "Got unexpected Neighbors from {:?} ; oversized packet ({} + {}) node_id={:#x}", &from, request.response_count, results_count, node_id);
 						false
 					}
 				};
 				if entry.get().response_count == BUCKET_SIZE {
 					entry.remove();
 				}
-				result
+				expected
 			}
-			Entry::Vacant(_) => false,
+			Entry::Vacant(_) => {
+				debug!(target: "discovery", "Got unexpected Neighbors from {:?} ; couldn't find node_id={:#x}", &from, node_id);
+				false
+			},
 		};

 		if !is_expected {
-			debug!(target: "discovery", "Got unexpected Neighbors from {:?}", &from);
 			return Ok(None);
 		}

@ -591,65 +626,74 @@ impl<'a> Discovery<'a> {
 		Ok(None)
 	}

-	fn check_expired(&mut self, time: Instant) -> HashSet<NodeId> {
-		let mut removed: HashSet<NodeId> = HashSet::new();
-		while let Some((node_id, sent_at)) = self.expiring_pings.pop_front() {
-			if time.duration_since(sent_at) <= PING_TIMEOUT {
-				self.expiring_pings.push_front((node_id, sent_at));
-				break;
+	fn check_expired(&mut self, time: Instant) {
+		let mut nodes_to_expire = Vec::new();
+		self.in_flight_pings.retain(|node_id, ping_request| {
+			if time.duration_since(ping_request.sent_at) > PING_TIMEOUT {
+				debug!(target: "discovery", "Removing expired PING request for node_id={:#x}", node_id);
+				nodes_to_expire.push(*node_id);
+				false
+			} else {
+				true
 			}
-			self.expire_in_flight_request(node_id, sent_at, &mut removed);
-		}
-		while let Some((node_id, sent_at)) = self.expiring_finds.pop_front() {
-			if time.duration_since(sent_at) <= FIND_NODE_TIMEOUT {
-				self.expiring_finds.push_front((node_id, sent_at));
-				break;
-			}
-			self.expire_in_flight_request(node_id, sent_at, &mut removed);
-		}
-		removed
-	}
-
-	fn expire_in_flight_request(&mut self, node_id: NodeId, sent_at: Instant, removed: &mut HashSet<NodeId>) {
-		if let Entry::Occupied(entry) = self.in_flight_requests.entry(node_id) {
-			if entry.get().sent_at == sent_at {
-				entry.remove();
-
-				// Attempt to remove from bucket if in one.
-				let id_hash = keccak(&node_id);
-				let dist = Discovery::distance(&self.id_hash, &id_hash)
-					.expect("distance is None only if id hashes are equal; will never send request to self; qed");
-				let bucket = &mut self.node_buckets[dist];
-				if let Some(index) = bucket.nodes.iter().position(|n| n.id_hash == id_hash) {
-					if bucket.nodes[index].fail_count < self.request_backoff.len() {
-						let node = &mut bucket.nodes[index];
-						node.backoff_until = Instant::now() + self.request_backoff[node.fail_count];
-						node.fail_count += 1;
-						trace!(
-							target: "discovery",
-							"Requests to node {:?} timed out {} consecutive time(s)",
-							&node.address, node.fail_count
-						);
-					} else {
-						removed.insert(node_id);
-						let node = bucket.nodes.remove(index).expect("index was located in if condition");
-						debug!(target: "discovery", "Removed expired node {:?}", &node.address);
-					}
+		});
+		self.in_flight_find_nodes.retain(|node_id, find_node_request| {
+			if time.duration_since(find_node_request.sent_at) > FIND_NODE_TIMEOUT {
+				if !find_node_request.answered {
+					debug!(target: "discovery", "Removing expired FIND NODE request for node_id={:#x}", node_id);
+					nodes_to_expire.push(*node_id);
 				}
+				false
+			} else {
+				true
+			}
+		});
+		for node_id in nodes_to_expire {
+			self.expire_node_request(node_id);
+		}
+	}
+
+	fn expire_node_request(&mut self, node_id: NodeId) {
+		// Attempt to remove from bucket if in one.
+		let id_hash = keccak(&node_id);
+		let dist = Discovery::distance(&self.id_hash, &id_hash)
+			.expect("distance is None only if id hashes are equal; will never send request to self; qed");
+		let bucket = &mut self.node_buckets[dist];
+		if let Some(index) = bucket.nodes.iter().position(|n| n.id_hash == id_hash) {
+			if bucket.nodes[index].fail_count < self.request_backoff.len() {
+				let node = &mut bucket.nodes[index];
+				node.backoff_until = Instant::now() + self.request_backoff[node.fail_count];
+				node.fail_count += 1;
+				trace!(
+					target: "discovery",
+					"Requests to node {:?} timed out {} consecutive time(s)",
+					&node.address, node.fail_count
+				);
+			} else {
+				let node = bucket.nodes.remove(index).expect("index was located in if condition");
+				debug!(target: "discovery", "Removed expired node {:?}", &node.address);
 			}
 		}
 	}

-	pub fn round(&mut self) -> Option<TableUpdates> {
-		let removed = self.check_expired(Instant::now());
-		self.discover();
-		if !removed.is_empty() {
-			Some(TableUpdates { added: HashMap::new(), removed })
-		} else { None }
+
+	pub fn round(&mut self) {
+		self.check_expired(Instant::now());
+		self.update_new_nodes();
+
+		if self.discovery_round.is_some() {
+			self.discover();
+		// Start discovering if the first pings have been sent (or timed out)
+		} else if self.in_flight_pings.len() == 0 && !self.discovery_initiated {
+			self.discovery_initiated = true;
+			self.refresh();
+		}
 	}

 	pub fn refresh(&mut self) {
-		self.start();
+		if self.discovery_round.is_none() {
+			self.start();
+		}
 	}

 	pub fn any_sends_queued(&self) -> bool {
@ -663,6 +707,16 @@ impl<'a> Discovery<'a> {
 	pub fn requeue_send(&mut self, datagram: Datagram) {
 		self.send_queue.push_front(datagram)
 	}
+
+	/// Add a list of known nodes to the table.
+	#[cfg(test)]
+	pub fn init_node_list(&mut self, nodes: Vec<NodeEntry>) {
+		for n in nodes {
+			if self.is_allowed(&n) {
+				self.update_node(n);
+			}
+		}
+	}
 }

 fn append_expiration(rlp: &mut RlpStream) {
@ -738,13 +792,13 @@ mod tests {

 		for i in 1..(MAX_NODES_PING+1) {
 			discovery.add_node(NodeEntry { id: NodeId::random(), endpoint: ep.clone() });
-			assert_eq!(discovery.in_flight_requests.len(), i);
+			assert_eq!(discovery.in_flight_pings.len(), i);
 			assert_eq!(discovery.send_queue.len(), i);
 			assert_eq!(discovery.adding_nodes.len(), 0);
 		}
 		for i in 1..20 {
 			discovery.add_node(NodeEntry { id: NodeId::random(), endpoint: ep.clone() });
-			assert_eq!(discovery.in_flight_requests.len(), MAX_NODES_PING);
+			assert_eq!(discovery.in_flight_pings.len(), MAX_NODES_PING);
 			assert_eq!(discovery.send_queue.len(), MAX_NODES_PING);
 			assert_eq!(discovery.adding_nodes.len(), i);
 		}
@ -821,23 +875,29 @@ mod tests {
 		assert_eq!(total_bucket_nodes(&discovery.node_buckets), 1200);

 		// Requests have not expired yet.
-		let removed = discovery.check_expired(Instant::now()).len();
+		let num_nodes = total_bucket_nodes(&discovery.node_buckets);
+		discovery.check_expired(Instant::now());
+		let removed = num_nodes - total_bucket_nodes(&discovery.node_buckets);
 		assert_eq!(removed, 0);

 		// Expiring pings to bucket nodes removes them from bucket.
-		let removed = discovery.check_expired(Instant::now() + PING_TIMEOUT).len();
+		let num_nodes = total_bucket_nodes(&discovery.node_buckets);
+		discovery.check_expired(Instant::now() + PING_TIMEOUT);
+		let removed = num_nodes - total_bucket_nodes(&discovery.node_buckets);
 		assert!(removed > 0);
 		assert_eq!(total_bucket_nodes(&discovery.node_buckets), 1200 - removed);

 		for _ in 0..100 {
 			discovery.add_node(NodeEntry { id: NodeId::random(), endpoint: ep.clone() });
 		}
-		assert!(discovery.in_flight_requests.len() > 0);
+		assert!(discovery.in_flight_pings.len() > 0);

 		// Expire pings to nodes that are not in buckets.
-		let removed = discovery.check_expired(Instant::now() + PING_TIMEOUT).len();
+		let num_nodes = total_bucket_nodes(&discovery.node_buckets);
+		discovery.check_expired(Instant::now() + PING_TIMEOUT);
+		let removed = num_nodes - total_bucket_nodes(&discovery.node_buckets);
 		assert_eq!(removed, 0);
-		assert_eq!(discovery.in_flight_requests.len(), 0);
+		assert_eq!(discovery.in_flight_pings.len(), 0);

 		let from = SocketAddr::from_str("99.99.99.99:40445").unwrap();

@ -849,7 +909,9 @@ mod tests {
 			discovery.on_packet(&packet, from.clone()).unwrap();
 		}

-		let removed = discovery.check_expired(Instant::now() + FIND_NODE_TIMEOUT).len();
+		let num_nodes = total_bucket_nodes(&discovery.node_buckets);
+		discovery.check_expired(Instant::now() + FIND_NODE_TIMEOUT);
+		let removed = num_nodes - total_bucket_nodes(&discovery.node_buckets);
 		assert!(removed > 0);

 		// FIND_NODE does not time out because it receives k results.
@ -859,7 +921,9 @@ mod tests {
 			discovery.on_packet(&packet, from.clone()).unwrap();
 		}

-		let removed = discovery.check_expired(Instant::now() + FIND_NODE_TIMEOUT).len();
+		let num_nodes = total_bucket_nodes(&discovery.node_buckets);
+		discovery.check_expired(Instant::now() + FIND_NODE_TIMEOUT);
+		let removed = num_nodes - total_bucket_nodes(&discovery.node_buckets);
 		assert_eq!(removed, 0);

 		// Test bucket evictions with retries.
@ -868,12 +932,16 @@ mod tests {

 		for _ in 0..2 {
 			discovery.ping(&node_entries[101]).unwrap();
-			let removed = discovery.check_expired(Instant::now() + PING_TIMEOUT).len();
+			let num_nodes = total_bucket_nodes(&discovery.node_buckets);
+			discovery.check_expired(Instant::now() + PING_TIMEOUT);
+			let removed = num_nodes - total_bucket_nodes(&discovery.node_buckets);
 			assert_eq!(removed, 0);
 		}

 		discovery.ping(&node_entries[101]).unwrap();
-		let removed = discovery.check_expired(Instant::now() + PING_TIMEOUT).len();
+		let num_nodes = total_bucket_nodes(&discovery.node_buckets);
+		discovery.check_expired(Instant::now() + PING_TIMEOUT);
+		let removed = num_nodes - total_bucket_nodes(&discovery.node_buckets);
 		assert_eq!(removed, 1);
 	}

@ -1066,9 +1134,11 @@ mod tests {
 		assert_eq!(ep1, NodeEndpoint::from_rlp(&rlp.at(1).unwrap()).unwrap());
 		assert_eq!(ep2, NodeEndpoint::from_rlp(&rlp.at(2).unwrap()).unwrap());

+		// `discovery1` should be added to node table on ping received
 		if let Some(_) = discovery2.on_packet(&ping_data.payload, ep1.address.clone()).unwrap() {
 			panic!("Expected no changes to discovery2's table");
 		}
+
 		let pong_data = discovery2.dequeue_send().unwrap();
 		let data = &pong_data.payload[(32 + 65)..];
 		assert_eq!(data[0], PACKET_PONG);
--- a/util/network-devp2p/src/host.rs
+++ b/util/network-devp2p/src/host.rs
@ -59,8 +59,9 @@ const TCP_ACCEPT: StreamToken = SYS_TIMER + 1;
 const IDLE: TimerToken = SYS_TIMER + 2;
 const DISCOVERY: StreamToken = SYS_TIMER + 3;
 const DISCOVERY_REFRESH: TimerToken = SYS_TIMER + 4;
-const DISCOVERY_ROUND: TimerToken = SYS_TIMER + 5;
-const NODE_TABLE: TimerToken = SYS_TIMER + 6;
+const FAST_DISCOVERY_REFRESH: TimerToken = SYS_TIMER + 5;
+const DISCOVERY_ROUND: TimerToken = SYS_TIMER + 6;
+const NODE_TABLE: TimerToken = SYS_TIMER + 7;
 const FIRST_SESSION: StreamToken = 0;
 const LAST_SESSION: StreamToken = FIRST_SESSION + MAX_SESSIONS - 1;
 const USER_TIMER: TimerToken = LAST_SESSION + 256;
@ -71,6 +72,8 @@ const SYS_TIMER: TimerToken = LAST_SESSION + 1;
 const MAINTENANCE_TIMEOUT: Duration = Duration::from_secs(1);
 // for DISCOVERY_REFRESH TimerToken
 const DISCOVERY_REFRESH_TIMEOUT: Duration = Duration::from_secs(60);
+// for FAST_DISCOVERY_REFRESH TimerToken
+const FAST_DISCOVERY_REFRESH_TIMEOUT: Duration = Duration::from_secs(10);
 // for DISCOVERY_ROUND TimerToken
 const DISCOVERY_ROUND_TIMEOUT: Duration = Duration::from_millis(300);
 // for NODE_TABLE TimerToken
@ -478,10 +481,10 @@ impl Host {
 			let socket = UdpSocket::bind(&udp_addr).expect("Error binding UDP socket");
 			*self.udp_socket.lock() = Some(socket);

-			discovery.init_node_list(self.nodes.read().entries());
 			discovery.add_node_list(self.nodes.read().entries());
 			*self.discovery.lock() = Some(discovery);
 			io.register_stream(DISCOVERY)?;
+			io.register_timer(FAST_DISCOVERY_REFRESH, FAST_DISCOVERY_REFRESH_TIMEOUT)?;
 			io.register_timer(DISCOVERY_REFRESH, DISCOVERY_REFRESH_TIMEOUT)?;
 			io.register_timer(DISCOVERY_ROUND, DISCOVERY_ROUND_TIMEOUT)?;
 		}
@ -533,6 +536,18 @@ impl Host {
 		}
 	}

+	fn has_enough_peers(&self) -> bool {
+		let min_peers = {
+			let info = self.info.read();
+			let config = &info.config;
+
+			config.min_peers
+		};
+		let (_, egress_count, ingress_count) = self.session_count();
+
+		return egress_count + ingress_count >= min_peers as usize;
+	}
+
 	fn connect_peers(&self, io: &IoContext<NetworkIoMessage>) {
 		let (min_peers, mut pin, max_handshakes, allow_ips, self_id) = {
 			let info = self.info.read();
@ -1014,16 +1029,23 @@ impl IoHandler<NetworkIoMessage> for Host {
 			IDLE => self.maintain_network(io),
 			FIRST_SESSION ... LAST_SESSION => self.connection_timeout(token, io),
 			DISCOVERY_REFRESH => {
-				if let Some(d) = self.discovery.lock().as_mut() {
-					d.refresh();
-                                }
+				// Run the _slow_ discovery if enough peers are connected
+				if !self.has_enough_peers() {
+					return;
+				}
+				self.discovery.lock().as_mut().map(|d| d.refresh());
+				io.update_registration(DISCOVERY).unwrap_or_else(|e| debug!("Error updating discovery registration: {:?}", e));
+			},
+			FAST_DISCOVERY_REFRESH => {
+				// Run the fast discovery if not enough peers are connected
+				if self.has_enough_peers() {
+					return;
+				}
+				self.discovery.lock().as_mut().map(|d| d.refresh());
 				io.update_registration(DISCOVERY).unwrap_or_else(|e| debug!("Error updating discovery registration: {:?}", e));
 			},
 			DISCOVERY_ROUND => {
-				let node_changes = { self.discovery.lock().as_mut().and_then(|d| d.round()) };
-				if let Some(node_changes) = node_changes {
-					self.update_nodes(io, node_changes);
-				}
+				self.discovery.lock().as_mut().map(|d| d.round());
 				io.update_registration(DISCOVERY).unwrap_or_else(|e| debug!("Error updating discovery registration: {:?}", e));
 			},
 			NODE_TABLE => {
--- a/util/network-devp2p/src/node_table.rs
+++ b/util/network-devp2p/src/node_table.rs
@ -385,7 +385,7 @@ impl NodeTable {
 			None => return,
 		};
 		if let Err(e) = fs::create_dir_all(&path) {
-			warn!("Error creating node table directory: {:?}", e);
+			warn!(target: "network", "Error creating node table directory: {:?}", e);
 			return;
 		}
 		path.push(NODES_FILE);
@ -400,11 +400,11 @@ impl NodeTable {
 		match fs::File::create(&path) {
 			Ok(file) => {
 				if let Err(e) = serde_json::to_writer_pretty(file, &table) {
-					warn!("Error writing node table file: {:?}", e);
+					warn!(target: "network", "Error writing node table file: {:?}", e);
 				}
 			},
 			Err(e) => {
-				warn!("Error creating node table file: {:?}", e);
+				warn!(target: "network", "Error creating node table file: {:?}", e);
 			}
 		}
 	}
@ -418,7 +418,7 @@ impl NodeTable {
 		let file = match fs::File::open(&path) {
 			Ok(file) => file,
 			Err(e) => {
-				debug!("Error opening node table file: {:?}", e);
+				debug!(target: "network", "Error opening node table file: {:?}", e);
 				return Default::default();
 			},
 		};
@ -431,7 +431,7 @@ impl NodeTable {
 					.collect()
 			},
 			Err(e) => {
-				warn!("Error reading node table file: {:?}", e);
+				warn!(target: "network", "Error reading node table file: {:?}", e);
 				Default::default()
 			},
 		}
--- a/util/patricia-trie-ethereum/Cargo.toml
+++ b/util/patricia-trie-ethereum/Cargo.toml
@ -6,7 +6,7 @@ description = "Merkle-Patricia Trie (Ethereum Style)"
 license = "GPL-3.0"

 [dependencies]
-patricia-trie = "0.2.1"
+patricia-trie = "0.2"
 keccak-hasher = { version = "0.1.1", path = "../keccak-hasher" }
 hashdb = "0.2"
 rlp = { version = "0.2.4", features = ["ethereum"] }
--- a/util/version/Cargo.toml
+++ b/util/version/Cargo.toml
@ -10,15 +10,15 @@ build = "build.rs"
 [package.metadata]
 # This versions track. Should be changed to `stable` or `beta` when on respective branches.
 # Used by auto-updater and for Parity version string.
-track = "nightly"
+track = "beta"

 # Network specific settings, used ONLY by auto-updater.
 # Latest supported fork blocks.
 # Indicates a critical release in this track (i.e. consensus issue).
 [package.metadata.networks]
-foundation = { forkBlock = 4370000, critical = false }
-ropsten = { forkBlock = 10, critical = false }
-kovan = { forkBlock = 6600000, critical = false }
+foundation = { forkBlock = 4370000, critical = true }
+ropsten = { forkBlock = 10, critical = true }
+kovan = { forkBlock = 6600000, critical = true }

 [dependencies]
 parity-bytes = "0.1"