Don't send ActiveLeaves from leaves in db on startup in Overseer (#6727)

* Don't send `ActiveLeaves` from leaves in db on startup in Overseer. Wait for fresh leaves instead.

* Don't pass initial set of leaves to Overseer

* Fix compilation error in subsystem-test-helpers

polkadot/node/overseer/src/dummy.rs

@@ -190,7 +190,6 @@ where
 		.span_per_active_leaf(Default::default())
 		.active_leaves(Default::default())
 		.known_leaves(LruCache::new(KNOWN_LEAVES_CACHE_SIZE))
-		.leaves(Default::default())
 		.spawner(SpawnGlue(spawner))
 		.metrics(metrics)
 		.supports_parachains(supports_parachains);

polkadot/node/overseer/src/lib.rs

@@ -612,11 +612,6 @@ pub struct Overseer<SupportsParachains> {
 	/// Stores the [`jaeger::Span`] per active leaf.
 	pub span_per_active_leaf: HashMap<Hash, Arc<jaeger::Span>>,
 
-	/// A set of leaves that `Overseer` starts working with.
-	///
-	/// Drained at the beginning of `run` and never used again.
-	pub leaves: Vec<(Hash, BlockNumber)>,
-
 	/// The set of the "active leaves".
 	pub active_leaves: HashMap<Hash, BlockNumber>,
 
@@ -728,16 +723,6 @@ where
 		let metrics = self.metrics.clone();
 		spawn_metronome_metrics(&mut self, metrics)?;
 
-		// Notify about active leaves on startup before starting the loop
-		for (hash, number) in std::mem::take(&mut self.leaves) {
-			let _ = self.active_leaves.insert(hash, number);
-			if let Some((span, status)) = self.on_head_activated(&hash, None).await {
-				let update =
-					ActiveLeavesUpdate::start_work(ActivatedLeaf { hash, number, status, span });
-				self.broadcast_signal(OverseerSignal::ActiveLeaves(update)).await?;
-			}
-		}
-
 		loop {
 			select! {
 				msg = self.events_rx.select_next_some() => {

polkadot/node/overseer/src/tests.rs

@@ -47,14 +47,6 @@ use sp_core::crypto::Pair as _;
 
 use super::*;
 
-fn block_info_to_pair(blocks: impl IntoIterator<Item = BlockInfo>) -> Vec<(Hash, BlockNumber)> {
-	Vec::from_iter(
-		blocks
-			.into_iter()
-			.map(|BlockInfo { hash, parent_hash: _, number }| (hash, number)),
-	)
-}
-
 type SpawnedSubsystem = crate::gen::SpawnedSubsystem<SubsystemError>;
 
 struct TestSubsystem1(metered::MeteredSender<usize>);
@@ -223,20 +215,16 @@ fn overseer_metrics_work() {
 	executor::block_on(async move {
 		let first_block_hash = [1; 32].into();
 		let second_block_hash = [2; 32].into();
-		let third_block_hash = [3; 32].into();
 
 		let first_block =
 			BlockInfo { hash: first_block_hash, parent_hash: [0; 32].into(), number: 1 };
 		let second_block =
 			BlockInfo { hash: second_block_hash, parent_hash: first_block_hash, number: 2 };
-		let third_block =
-			BlockInfo { hash: third_block_hash, parent_hash: second_block_hash, number: 3 };
 
 		let registry = prometheus::Registry::new();
 		let (overseer, handle) =
 			dummy_overseer_builder(spawner, MockSupportsParachains, Some(&registry))
 				.unwrap()
-				.leaves(block_info_to_pair(vec![first_block]))
 				.build()
 				.unwrap();
 
@@ -245,8 +233,8 @@ fn overseer_metrics_work() {
 
 		pin_mut!(overseer_fut);
 
+		handle.block_imported(first_block).await;
 		handle.block_imported(second_block).await;
-		handle.block_imported(third_block).await;
 		handle
 			.send_msg_anon(AllMessages::CandidateValidation(test_candidate_validation_msg()))
 			.await;
@@ -256,8 +244,8 @@ fn overseer_metrics_work() {
 			res = overseer_fut => {
 				assert!(res.is_ok());
 				let metrics = extract_metrics(&registry);
-				assert_eq!(metrics["activated"], 3);
-				assert_eq!(metrics["deactivated"], 2);
+				assert_eq!(metrics["activated"], 2);
+				assert_eq!(metrics["deactivated"], 1);
 				assert_eq!(metrics["relayed"], 1);
 			},
 			complete => (),
@@ -379,14 +367,11 @@ fn overseer_start_stop_works() {
 	executor::block_on(async move {
 		let first_block_hash = [1; 32].into();
 		let second_block_hash = [2; 32].into();
-		let third_block_hash = [3; 32].into();
 
 		let first_block =
 			BlockInfo { hash: first_block_hash, parent_hash: [0; 32].into(), number: 1 };
 		let second_block =
 			BlockInfo { hash: second_block_hash, parent_hash: first_block_hash, number: 2 };
-		let third_block =
-			BlockInfo { hash: third_block_hash, parent_hash: second_block_hash, number: 3 };
 
 		let (tx_5, mut rx_5) = metered::channel(64);
 		let (tx_6, mut rx_6) = metered::channel(64);
@@ -395,7 +380,6 @@ fn overseer_start_stop_works() {
 			.unwrap()
 			.replace_candidate_validation(move |_| TestSubsystem5(tx_5))
 			.replace_candidate_backing(move |_| TestSubsystem6(tx_6))
-			.leaves(block_info_to_pair(vec![first_block]))
 			.build()
 			.unwrap();
 		let mut handle = Handle::new(handle);
@@ -406,16 +390,19 @@ fn overseer_start_stop_works() {
 		let mut ss5_results = Vec::new();
 		let mut ss6_results = Vec::new();
 
+		handle.block_imported(first_block).await;
 		handle.block_imported(second_block).await;
-		handle.block_imported(third_block).await;
 
 		let expected_heartbeats = vec![
-			OverseerSignal::ActiveLeaves(ActiveLeavesUpdate::start_work(ActivatedLeaf {
-				hash: first_block_hash,
-				number: 1,
-				span: Arc::new(jaeger::Span::Disabled),
-				status: LeafStatus::Fresh,
-			})),
+			OverseerSignal::ActiveLeaves(ActiveLeavesUpdate {
+				activated: Some(ActivatedLeaf {
+					hash: first_block_hash,
+					number: 1,
+					span: Arc::new(jaeger::Span::Disabled),
+					status: LeafStatus::Fresh,
+				}),
+				deactivated: Default::default(),
+			}),
 			OverseerSignal::ActiveLeaves(ActiveLeavesUpdate {
 				activated: Some(ActivatedLeaf {
 					hash: second_block_hash,
@@ -425,15 +412,6 @@ fn overseer_start_stop_works() {
 				}),
 				deactivated: [first_block_hash].as_ref().into(),
 			}),
-			OverseerSignal::ActiveLeaves(ActiveLeavesUpdate {
-				activated: Some(ActivatedLeaf {
-					hash: third_block_hash,
-					number: 3,
-					span: Arc::new(jaeger::Span::Disabled),
-					status: LeafStatus::Fresh,
-				}),
-				deactivated: [second_block_hash].as_ref().into(),
-			}),
 		];
 
 		loop {
@@ -494,7 +472,6 @@ fn overseer_finalize_works() {
 			.unwrap()
 			.replace_candidate_validation(move |_| TestSubsystem5(tx_5))
 			.replace_candidate_backing(move |_| TestSubsystem6(tx_6))
-			.leaves(block_info_to_pair(vec![first_block, second_block]))
 			.build()
 			.unwrap();
 		let mut handle = Handle::new(handle);
@@ -505,22 +482,32 @@ fn overseer_finalize_works() {
 		let mut ss5_results = Vec::new();
 		let mut ss6_results = Vec::new();
 
+		// activate two blocks
+		handle.block_imported(first_block).await;
+		handle.block_imported(second_block).await;
+
 		// this should stop work on both forks we started with earlier.
 		handle.block_finalized(third_block).await;
 
 		let expected_heartbeats = vec![
-			OverseerSignal::ActiveLeaves(ActiveLeavesUpdate::start_work(ActivatedLeaf {
-				hash: first_block_hash,
-				number: 1,
-				span: Arc::new(jaeger::Span::Disabled),
-				status: LeafStatus::Fresh,
-			})),
-			OverseerSignal::ActiveLeaves(ActiveLeavesUpdate::start_work(ActivatedLeaf {
-				hash: second_block_hash,
-				number: 2,
-				span: Arc::new(jaeger::Span::Disabled),
-				status: LeafStatus::Fresh,
-			})),
+			OverseerSignal::ActiveLeaves(ActiveLeavesUpdate {
+				activated: Some(ActivatedLeaf {
+					hash: first_block_hash,
+					number: 1,
+					span: Arc::new(jaeger::Span::Disabled),
+					status: LeafStatus::Fresh,
+				}),
+				deactivated: Default::default(),
+			}),
+			OverseerSignal::ActiveLeaves(ActiveLeavesUpdate {
+				activated: Some(ActivatedLeaf {
+					hash: second_block_hash,
+					number: 2,
+					span: Arc::new(jaeger::Span::Disabled),
+					status: LeafStatus::Fresh,
+				}),
+				deactivated: Default::default(),
+			}),
 			OverseerSignal::ActiveLeaves(ActiveLeavesUpdate {
 				deactivated: [first_block_hash, second_block_hash].as_ref().into(),
 				..Default::default()
@@ -590,7 +577,6 @@ fn overseer_finalize_leaf_preserves_it() {
 			.unwrap()
 			.replace_candidate_validation(move |_| TestSubsystem5(tx_5))
 			.replace_candidate_backing(move |_| TestSubsystem6(tx_6))
-			.leaves(block_info_to_pair(vec![first_block.clone(), second_block]))
 			.build()
 			.unwrap();
 		let mut handle = Handle::new(handle);
@@ -601,6 +587,8 @@ fn overseer_finalize_leaf_preserves_it() {
 		let mut ss5_results = Vec::new();
 		let mut ss6_results = Vec::new();
 
+		handle.block_imported(first_block.clone()).await;
+		handle.block_imported(second_block).await;
 		// This should stop work on the second block, but only the
 		// second block.
 		handle.block_finalized(first_block).await;

polkadot/node/service/src/lib.rs

@@ -49,7 +49,6 @@ use {
 	polkadot_node_network_protocol::{
 		peer_set::PeerSetProtocolNames, request_response::ReqProtocolNames,
 	},
-	polkadot_overseer::BlockInfo,
 	sc_client_api::BlockBackend,
 	sp_core::traits::SpawnNamed,
 	sp_trie::PrefixedMemoryDB,
@@ -129,10 +128,6 @@ pub use {rococo_runtime, rococo_runtime_constants};
 #[cfg(feature = "westend-native")]
 pub use {westend_runtime, westend_runtime_constants};
 
-/// The maximum number of active leaves we forward to the [`Overseer`] on startup.
-#[cfg(any(test, feature = "full-node"))]
-const MAX_ACTIVE_LEAVES: usize = 4;
-
 /// Provides the header and block number for a hash.
 ///
 /// Decouples `sc_client_api::Backend` and `sp_blockchain::HeaderBackend`.
@@ -668,56 +663,6 @@ impl IsCollator {
 	}
 }
 
-/// Returns the active leaves the overseer should start with.
-#[cfg(feature = "full-node")]
-async fn active_leaves<RuntimeApi, ExecutorDispatch>(
-	select_chain: &impl SelectChain<Block>,
-	client: &FullClient<RuntimeApi, ExecutorDispatch>,
-) -> Result<Vec<BlockInfo>, Error>
-where
-	RuntimeApi: ConstructRuntimeApi<Block, FullClient<RuntimeApi, ExecutorDispatch>>
-		+ Send
-		+ Sync
-		+ 'static,
-	RuntimeApi::RuntimeApi:
-		RuntimeApiCollection<StateBackend = sc_client_api::StateBackendFor<FullBackend, Block>>,
-	ExecutorDispatch: NativeExecutionDispatch + 'static,
-{
-	let best_block = select_chain.best_chain().await?;
-
-	let mut leaves = select_chain
-		.leaves()
-		.await
-		.unwrap_or_default()
-		.into_iter()
-		.filter_map(|hash| {
-			let number = HeaderBackend::number(client, hash).ok()??;
-
-			// Only consider leaves that are in maximum an uncle of the best block.
-			if number < best_block.number().saturating_sub(1) {
-				return None
-			} else if hash == best_block.hash() {
-				return None
-			};
-
-			let parent_hash = client.header(hash).ok()??.parent_hash;
-
-			Some(BlockInfo { hash, parent_hash, number })
-		})
-		.collect::<Vec<_>>();
-
-	// Sort by block number and get the maximum number of leaves
-	leaves.sort_by_key(|b| b.number);
-
-	leaves.push(BlockInfo {
-		hash: best_block.hash(),
-		parent_hash: *best_block.parent_hash(),
-		number: *best_block.number(),
-	});
-
-	Ok(leaves.into_iter().rev().take(MAX_ACTIVE_LEAVES).collect())
-}
-
 pub const AVAILABILITY_CONFIG: AvailabilityConfig = AvailabilityConfig {
 	col_data: parachains_db::REAL_COLUMNS.col_availability_data,
 	col_meta: parachains_db::REAL_COLUMNS.col_availability_meta,
@@ -1009,10 +954,6 @@ where
 
 	let overseer_client = client.clone();
 	let spawner = task_manager.spawn_handle();
-	// Cannot use the `RelayChainSelection`, since that'd require a setup _and running_ overseer
-	// which we are about to setup.
-	let active_leaves =
-		futures::executor::block_on(active_leaves(select_chain.as_longest_chain(), &*client))?;
 
 	let authority_discovery_service = if auth_or_collator || overseer_enable_anyways {
 		use futures::StreamExt;
@@ -1068,7 +1009,6 @@ where
 			.generate::<service::SpawnTaskHandle, FullClient<RuntimeApi, ExecutorDispatch>>(
 				overseer_connector,
 				OverseerGenArgs {
-					leaves: active_leaves,
 					keystore,
 					runtime_client: overseer_client.clone(),
 					parachains_db,

polkadot/node/service/src/overseer.rs

@@ -34,8 +34,8 @@ pub use polkadot_overseer::{
 	HeadSupportsParachains,
 };
 use polkadot_overseer::{
-	metrics::Metrics as OverseerMetrics, BlockInfo, InitializedOverseerBuilder, MetricsTrait,
-	Overseer, OverseerConnector, OverseerHandle, SpawnGlue,
+	metrics::Metrics as OverseerMetrics, InitializedOverseerBuilder, MetricsTrait, Overseer,
+	OverseerConnector, OverseerHandle, SpawnGlue,
 };
 
 use polkadot_primitives::runtime_api::ParachainHost;
@@ -81,8 +81,6 @@ where
 	RuntimeClient::Api: ParachainHost<Block> + BabeApi<Block> + AuthorityDiscoveryApi<Block>,
 	Spawner: 'static + SpawnNamed + Clone + Unpin,
 {
-	/// Set of initial relay chain leaves to track.
-	pub leaves: Vec<BlockInfo>,
 	/// The keystore to use for i.e. validator keys.
 	pub keystore: Arc<LocalKeystore>,
 	/// Runtime client generic, providing the `ProvieRuntimeApi` trait besides others.
@@ -131,7 +129,6 @@ where
 /// with all default values.
 pub fn prepared_overseer_builder<Spawner, RuntimeClient>(
 	OverseerGenArgs {
-		leaves,
 		keystore,
 		runtime_client,
 		parachains_db,
@@ -309,11 +306,6 @@ where
 			Metrics::register(registry)?,
 		))
 		.chain_selection(ChainSelectionSubsystem::new(chain_selection_config, parachains_db))
-		.leaves(Vec::from_iter(
-			leaves
-				.into_iter()
-				.map(|BlockInfo { hash, parent_hash: _, number }| (hash, number)),
-		))
 		.activation_external_listeners(Default::default())
 		.span_per_active_leaf(Default::default())
 		.active_leaves(Default::default())

polkadot/node/subsystem-test-helpers/src/lib.rs

@@ -457,7 +457,6 @@ mod tests {
 			dummy_overseer_builder(spawner.clone(), AlwaysSupportsParachains, None)
 				.unwrap()
 				.replace_collator_protocol(|_| ForwardSubsystem(tx))
-				.leaves(vec![])
 				.build()
 				.unwrap();