Reduce CPU overhead of gossip (#10859)

substrate/Cargo.lock

@@ -64,9 +64,9 @@ dependencies = [
 
 [[package]]
 name = "ahash"
-version = "0.7.4"
+version = "0.7.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "43bb833f0bf979d8475d38fbf09ed3b8a55e1885fe93ad3f93239fc6a4f17b98"
+checksum = "fcb51a0695d8f838b1ee009b3fbf66bda078cd64590202a864a8f3e8c4315c47"
 dependencies = [
  "getrandom 0.2.3",
  "once_cell",
@@ -8333,6 +8333,7 @@ dependencies = [
 name = "sc-finality-grandpa"
 version = "0.10.0-dev"
 dependencies = [
+ "ahash",
  "assert_matches",
  "async-trait",
  "dyn-clone",
@@ -8491,6 +8492,7 @@ dependencies = [
 name = "sc-network-gossip"
 version = "0.10.0-dev"
 dependencies = [
+ "ahash",
  "async-std",
  "futures 0.3.16",
  "futures-timer",

substrate/client/finality-grandpa/Cargo.toml

@@ -22,6 +22,7 @@ futures-timer = "3.0.1"
 log = "0.4.8"
 parking_lot = "0.11.2"
 rand = "0.8.4"
+ahash = "0.7.6"
 parity-scale-codec = { version = "2.3.1", features = ["derive"] }
 sp-application-crypto = { version = "5.0.0", path = "../../primitives/application-crypto" }
 sp-arithmetic = { version = "4.0.0", path = "../../primitives/arithmetic" }

substrate/client/finality-grandpa/src/communication/gossip.rs

@@ -84,23 +84,23 @@
 //!
 //! We only send polite messages to peers,
 
-use parity_scale_codec::{Decode, Encode};
+use ahash::{AHashMap, AHashSet};
-use sc_network::{ObservedRole, PeerId, ReputationChange};
-use sc_network_gossip::{MessageIntent, ValidatorContext};
-use sp_finality_grandpa::AuthorityId;
-use sp_runtime::traits::{Block as BlockT, NumberFor, Zero};
-
 use log::{debug, trace};
+use parity_scale_codec::{Decode, Encode};
 use prometheus_endpoint::{register, CounterVec, Opts, PrometheusError, Registry, U64};
 use rand::seq::SliceRandom;
+use sc_network::{ObservedRole, PeerId, ReputationChange};
+use sc_network_gossip::{MessageIntent, ValidatorContext};
 use sc_telemetry::{telemetry, TelemetryHandle, CONSENSUS_DEBUG};
 use sc_utils::mpsc::{tracing_unbounded, TracingUnboundedReceiver, TracingUnboundedSender};
+use sp_finality_grandpa::AuthorityId;
+use sp_runtime::traits::{Block as BlockT, NumberFor, Zero};
 
 use super::{benefit, cost, Round, SetId};
 use crate::{environment, CatchUp, CompactCommit, SignedMessage};
 
 use std::{
-	collections::{HashMap, HashSet, VecDeque},
+	collections::{HashSet, VecDeque},
 	time::{Duration, Instant},
 };
 
@@ -260,7 +260,7 @@ const KEEP_RECENT_ROUNDS: usize = 3;
 struct KeepTopics<B: BlockT> {
 	current_set: SetId,
 	rounds: VecDeque<(Round, SetId)>,
-	reverse_map: HashMap<B::Hash, (Option<Round>, SetId)>,
+	reverse_map: AHashMap<B::Hash, (Option<Round>, SetId)>,
 }
 
 impl<B: BlockT> KeepTopics<B> {
@@ -268,7 +268,7 @@ impl<B: BlockT> KeepTopics<B> {
 		KeepTopics {
 			current_set: SetId(0),
 			rounds: VecDeque::with_capacity(KEEP_RECENT_ROUNDS + 2),
-			reverse_map: HashMap::new(),
+			reverse_map: Default::default(),
 		}
 	}
 
@@ -290,7 +290,7 @@ impl<B: BlockT> KeepTopics<B> {
 			let _ = self.rounds.pop_front();
 		}
 
-		let mut map = HashMap::with_capacity(KEEP_RECENT_ROUNDS + 3);
+		let mut map = AHashMap::with_capacity(KEEP_RECENT_ROUNDS + 3);
 		map.insert(super::global_topic::<B>(self.current_set.0), (None, self.current_set));
 
 		for &(round, set) in &self.rounds {
@@ -477,10 +477,10 @@ impl<N> PeerInfo<N> {
 
 /// The peers we're connected to in gossip.
 struct Peers<N> {
-	inner: HashMap<PeerId, PeerInfo<N>>,
+	inner: AHashMap<PeerId, PeerInfo<N>>,
 	/// The randomly picked set of `LUCKY_PEERS` we'll gossip to in the first stage of round
 	/// gossiping.
-	first_stage_peers: HashSet<PeerId>,
+	first_stage_peers: AHashSet<PeerId>,
 	/// The randomly picked set of peers we'll gossip to in the second stage of gossiping if the
 	/// first stage didn't allow us to spread the voting data enough to conclude the round. This
 	/// set should have size `sqrt(connected_peers)`.
@@ -492,10 +492,10 @@ struct Peers<N> {
 impl<N> Default for Peers<N> {
 	fn default() -> Self {
 		Peers {
-			inner: HashMap::new(),
+			inner: Default::default(),
-			first_stage_peers: HashSet::new(),
+			first_stage_peers: Default::default(),
-			second_stage_peers: HashSet::new(),
+			second_stage_peers: Default::default(),
-			lucky_light_peers: HashSet::new(),
+			lucky_light_peers: Default::default(),
 		}
 	}
 }
@@ -608,7 +608,7 @@ impl<N: Ord> Peers<N> {
 			}
 		});
 
-		let mut first_stage_peers = HashSet::new();
+		let mut first_stage_peers = AHashSet::new();
 		let mut second_stage_peers = HashSet::new();
 
 		// we start by allocating authorities to the first stage set and when the minimum of

substrate/client/network-gossip/Cargo.toml

@@ -20,6 +20,7 @@ futures-timer = "3.0.1"
 libp2p = { version = "0.40.0", default-features = false }
 log = "0.4.8"
 lru = "0.7.0"
+ahash = "0.7.6"
 prometheus-endpoint = { package = "substrate-prometheus-endpoint", version = "0.10.0-dev", path = "../../utils/prometheus" }
 sc-network = { version = "0.10.0-dev", path = "../network" }
 sp-runtime = { version = "5.0.0", path = "../../primitives/runtime" }

substrate/client/network-gossip/src/state_machine.rs

@@ -18,19 +18,13 @@
 
 use crate::{MessageIntent, Network, ValidationResult, Validator, ValidatorContext};
 
+use ahash::AHashSet;
 use libp2p::PeerId;
 use lru::LruCache;
 use prometheus_endpoint::{register, Counter, PrometheusError, Registry, U64};
 use sc_network::ObservedRole;
 use sp_runtime::traits::{Block as BlockT, Hash, HashFor};
-use std::{
+use std::{borrow::Cow, collections::HashMap, iter, sync::Arc, time, time::Instant};
-	borrow::Cow,
-	collections::{HashMap, HashSet},
-	iter,
-	sync::Arc,
-	time,
-	time::Instant,
-};
 
 // FIXME: Add additional spam/DoS attack protection: https://github.com/paritytech/substrate/issues/1115
 // NOTE: The current value is adjusted based on largest production network deployment (Kusama) and
@@ -56,7 +50,7 @@ mod rep {
 }
 
 struct PeerConsensus<H> {
-	known_messages: HashSet<H>,
+	known_messages: AHashSet<H>,
 }
 
 /// Topic stream message with sender.
@@ -204,7 +198,8 @@ impl<B: BlockT> ConsensusGossip<B> {
 			?role,
 			"Registering peer",
 		);
-		self.peers.insert(who.clone(), PeerConsensus { known_messages: HashSet::new() });
+		self.peers
+			.insert(who.clone(), PeerConsensus { known_messages: Default::default() });
 
 		let validator = self.validator.clone();
 		let mut context = NetworkContext { gossip: self, network };