Improve dispute-coordinator message burstiness handling (#5471)

* Increase message channel size to 2048

Signed-off-by: Andrei Sandu <andrei-mihail@parity.io>

* Use unbounded channel for reading data

Signed-off-by: Andrei Sandu <andrei-mihail@parity.io>

polkadot/node/core/provisioner/src/lib.rs

@@ -599,7 +599,8 @@ async fn request_disputes(
 		RequestType::Recent => DisputeCoordinatorMessage::RecentDisputes(tx),
 		RequestType::Active => DisputeCoordinatorMessage::ActiveDisputes(tx),
 	};
-	sender.send_message(msg.into()).await;
+	// Bounded by block production - `ProvisionerMessage::RequestInherentData`.
+	sender.send_unbounded_message(msg.into());
 
 	let recent_disputes = match rx.await {
 		Ok(r) => r,
@@ -617,9 +618,10 @@ async fn request_votes(
 	disputes_to_query: Vec<(SessionIndex, CandidateHash)>,
 ) -> Vec<(SessionIndex, CandidateHash, CandidateVotes)> {
 	let (tx, rx) = oneshot::channel();
-	sender
-		.send_message(DisputeCoordinatorMessage::QueryCandidateVotes(disputes_to_query, tx).into())
-		.await;
+	// Bounded by block production - `ProvisionerMessage::RequestInherentData`.
+	sender.send_unbounded_message(
+		DisputeCoordinatorMessage::QueryCandidateVotes(disputes_to_query, tx).into(),
+	);
 
 	match rx.await {
 		Ok(v) => v,

polkadot/node/network/dispute-distribution/src/sender/mod.rs

@@ -340,10 +340,10 @@ async fn get_active_disputes<Context: SubsystemContext>(
 	ctx: &mut Context,
 ) -> JfyiErrorResult<Vec<(SessionIndex, CandidateHash)>> {
 	let (tx, rx) = oneshot::channel();
-	ctx.send_message(AllMessages::DisputeCoordinator(DisputeCoordinatorMessage::ActiveDisputes(
-		tx,
-	)))
-	.await;
+	// Caller scope is in `update_leaves` and this is bounded by fork count.
+	ctx.send_unbounded_message(AllMessages::DisputeCoordinator(
+		DisputeCoordinatorMessage::ActiveDisputes(tx),
+	));
 	rx.await.map_err(|_| JfyiError::AskActiveDisputesCanceled)
 }
 
@@ -354,10 +354,10 @@ async fn get_candidate_votes<Context: SubsystemContext>(
 	candidate_hash: CandidateHash,
 ) -> JfyiErrorResult<Option<CandidateVotes>> {
 	let (tx, rx) = oneshot::channel();
-	ctx.send_message(AllMessages::DisputeCoordinator(
+	// Caller scope is in `update_leaves` and this is bounded by fork count.
+	ctx.send_unbounded_message(AllMessages::DisputeCoordinator(
 		DisputeCoordinatorMessage::QueryCandidateVotes(vec![(session_index, candidate_hash)], tx),
-	))
-	.await;
+	));
 	rx.await
 		.map(|v| v.get(0).map(|inner| inner.to_owned().2))
 		.map_err(|_| JfyiError::AskCandidateVotesCanceled)

polkadot/node/overseer/src/lib.rs

@@ -415,6 +415,7 @@ pub async fn forward_events<P: BlockchainEvents<Block>>(client: Arc<P>, mut hand
 	signal=OverseerSignal,
 	error=SubsystemError,
 	network=NetworkBridgeEvent<VersionedValidationProtocol>,
+	message_capacity=2048,
 )]
 pub struct Overseer<SupportsParachains> {
 	#[subsystem(no_dispatch, CandidateValidationMessage)]