feat: verify attestation gossip messages in batch

packages/beacon-node/src/chain/blocks/importBlock.ts

@@ -89,11 +89,14 @@ export async function importBlock(
 
   this.metrics?.importBlock.bySource.inc({source});
   this.logger.verbose("Added block to forkchoice and state cache", {slot: block.message.slot, root: blockRootHex});
-  this.emitter.emit(routes.events.EventType.block, {
-    block: toHexString(this.config.getForkTypes(block.message.slot).BeaconBlock.hashTreeRoot(block.message)),
-    slot: block.message.slot,
-    executionOptimistic: blockSummary != null && isOptimisticBlock(blockSummary),
-  });
+  // We want to import block asap so call all event handler in the next event loop
+  setTimeout(() => {
+    this.emitter.emit(routes.events.EventType.block, {
+      block: toHexString(this.config.getForkTypes(block.message.slot).BeaconBlock.hashTreeRoot(block.message)),
+      slot: block.message.slot,
+      executionOptimistic: blockSummary != null && isOptimisticBlock(blockSummary),
+    });
+  }, 0);
 
   // 3. Import attestations to fork choice
   //

packages/beacon-node/src/chain/bls/multithread/index.ts

@@ -133,7 +133,8 @@ export class BlsMultiThreadWorkerPool implements IBlsVerifier {
     // THe worker is not able to deserialize from uncompressed
     // `Error: err _wrapDeserialize`
     this.format = implementation === "blst-native" ? PointFormat.uncompressed : PointFormat.compressed;
-    this.workers = this.createWorkers(implementation, defaultPoolSize);
+    // 1 worker for the main thread
+    this.workers = this.createWorkers(implementation, defaultPoolSize - 1);
 
     if (metrics) {
       metrics.blsThreadPool.queueLength.addCollect(() => {

packages/beacon-node/src/chain/options.ts

@@ -26,6 +26,7 @@ export type IChainOptions = BlockProcessOpts &
     /** Option to load a custom kzg trusted setup in txt format */
     trustedSetup?: string;
     broadcastValidationStrictness?: string;
+    minSameMessageSignatureSetsToBatch: number;
   };
 
 export type BlockProcessOpts = {
@@ -83,4 +84,8 @@ export const defaultChainOptions: IChainOptions = {
   // for attestation validation, having this value ensures we don't have to regen states most of the time
   maxSkipSlots: 32,
   broadcastValidationStrictness: "warn",
+  // should be less than or equal to MIN_SIGNATURE_SETS_TO_BATCH_VERIFY
+  // batching too much may block the I/O thread so if useWorker=false, suggest this value to be 32
+  // since this batch attestation work is designed to work with useWorker=true, make this the lowest value
+  minSameMessageSignatureSetsToBatch: 2,
 };

packages/beacon-node/src/chain/validation/attestation.ts

@@ -5,11 +5,10 @@ import {ATTESTATION_SUBNET_COUNT, SLOTS_PER_EPOCH, ForkName, ForkSeq} from "@lod
 import {
   computeEpochAtSlot,
   CachedBeaconStateAllForks,
-  ISignatureSet,
   getAttestationDataSigningRoot,
   createSingleSignatureSetFromComponents,
+  SingleSignatureSet,
 } from "@lodestar/state-transition";
-import {IBeaconChain} from "..";
 import {AttestationError, AttestationErrorCode, GossipAction} from "../errors/index.js";
 import {MAXIMUM_GOSSIP_CLOCK_DISPARITY_SEC} from "../../constants/index.js";
 import {RegenCaller} from "../regen/index.js";
@@ -21,6 +20,13 @@ import {
 } from "../../util/sszBytes.js";
 import {AttestationDataCacheEntry} from "../seenCache/seenAttestationData.js";
 import {sszDeserializeAttestation} from "../../network/gossip/topic.js";
+import {Result, wrapError} from "../../util/wrapError.js";
+import {IBeaconChain} from "../interface.js";
+
+export type BatchResult = {
+  results: Result<AttestationValidationResult>[];
+  batchableBls: boolean;
+};
 
 export type AttestationValidationResult = {
   attestation: phase0.Attestation;
@@ -40,6 +46,12 @@ export type GossipAttestation = {
   serializedData: Uint8Array;
   // available in NetworkProcessor since we check for unknown block root attestations
   attSlot: Slot;
+  attDataBase64?: string | null;
+};
+
+export type Phase0Result = AttestationValidationResult & {
+  signatureSet: SingleSignatureSet;
+  validatorIndex: number;
 };
 
 /**
@@ -48,13 +60,6 @@ export type GossipAttestation = {
  */
 const SHUFFLING_LOOK_AHEAD_EPOCHS = 1;
 
-/**
- * Validate attestations from gossip
- * - Only deserialize the attestation if needed, use the cached AttestationData instead
- * - This is to avoid deserializing similar attestation multiple times which could help the gc
- * - subnet is required
- * - do not prioritize bls signature set
- */
 export async function validateGossipAttestation(
   fork: ForkName,
   chain: IBeaconChain,
@@ -65,6 +70,105 @@ export async function validateGossipAttestation(
   return validateAttestation(fork, chain, attestationOrBytes, subnet);
 }
 
+/**
+ * Verify gossip attestations of the same attestation data. The main advantage is we can batch verify bls signatures
+ * through verifySignatureSetsSameMessage bls api to improve performance.
+ *   - If there are less than 2 signatures (minSameMessageSignatureSetsToBatch), verify each signature individually with batchable = true
+ *   - do not prioritize bls signature set
+ */
+export async function validateGossipAttestationsSameAttData(
+  fork: ForkName,
+  chain: IBeaconChain,
+  attestationOrBytesArr: AttestationOrBytes[],
+  subnet: number,
+  // for unit test, consumers do not need to pass this
+  phase0ValidationFn = validateGossipAttestationNoSignatureCheck
+): Promise<BatchResult> {
+  if (attestationOrBytesArr.length === 0) {
+    return {results: [], batchableBls: false};
+  }
+
+  // phase0: do all verifications except for signature verification
+  const phase0ResultOrErrors = await Promise.all(
+    attestationOrBytesArr.map((attestationOrBytes) =>
+      wrapError(phase0ValidationFn(fork, chain, attestationOrBytes, subnet))
+    )
+  );
+
+  // phase1: verify signatures of all valid attestations
+  // map new index to index in resultOrErrors
+  const newIndexToOldIndex = new Map<number, number>();
+  const signatureSets: SingleSignatureSet[] = [];
+  let newIndex = 0;
+  const phase0Results: Phase0Result[] = [];
+  for (const [i, resultOrError] of phase0ResultOrErrors.entries()) {
+    if (resultOrError.err) {
+      continue;
+    }
+    phase0Results.push(resultOrError.result);
+    newIndexToOldIndex.set(newIndex, i);
+    signatureSets.push(resultOrError.result.signatureSet);
+    newIndex++;
+  }
+
+  let signatureValids: boolean[];
+  const batchableBls = signatureSets.length >= chain.opts.minSameMessageSignatureSetsToBatch;
+  if (batchableBls) {
+    // all signature sets should have same signing root since we filtered in network processor
+    signatureValids = await chain.bls.verifySignatureSetsSameMessage(
+      signatureSets.map((set) => ({publicKey: set.pubkey, signature: set.signature})),
+      signatureSets[0].signingRoot
+    );
+  } else {
+    // don't want to block the main thread if there are too few signatures
+    signatureValids = await Promise.all(
+      signatureSets.map((set) => chain.bls.verifySignatureSets([set], {batchable: true}))
+    );
+  }
+
+  // phase0 post validation
+  for (const [i, sigValid] of signatureValids.entries()) {
+    const oldIndex = newIndexToOldIndex.get(i);
+    if (oldIndex == null) {
+      // should not happen
+      throw Error(`Cannot get old index for index ${i}`);
+    }
+
+    const {validatorIndex, attestation} = phase0Results[i];
+    const targetEpoch = attestation.data.target.epoch;
+    if (sigValid) {
+      // Now that the attestation has been fully verified, store that we have received a valid attestation from this validator.
+      //
+      // It's important to double check that the attestation still hasn't been observed, since
+      // there can be a race-condition if we receive two attestations at the same time and
+      // process them in different threads.
+      if (chain.seenAttesters.isKnown(targetEpoch, validatorIndex)) {
+        phase0ResultOrErrors[oldIndex] = {
+          err: new AttestationError(GossipAction.IGNORE, {
+            code: AttestationErrorCode.ATTESTATION_ALREADY_KNOWN,
+            targetEpoch,
+            validatorIndex,
+          }),
+        };
+      }
+
+      // valid
+      chain.seenAttesters.add(targetEpoch, validatorIndex);
+    } else {
+      phase0ResultOrErrors[oldIndex] = {
+        err: new AttestationError(GossipAction.IGNORE, {
+          code: AttestationErrorCode.INVALID_SIGNATURE,
+        }),
+      };
+    }
+  }
+
+  return {
+    results: phase0ResultOrErrors,
+    batchableBls,
+  };
+}
+
 /**
  * Validate attestations from api
  * - no need to deserialize attestation
@@ -81,17 +185,42 @@ export async function validateApiAttestation(
 }
 
 /**
- * Only deserialize the attestation if needed, use the cached AttestationData instead
- * This is to avoid deserializing similar attestation multiple times which could help the gc
+ * Validate a single unaggregated attestation
+ * subnet is null for api attestations
  */
-async function validateAttestation(
+export async function validateAttestation(
   fork: ForkName,
   chain: IBeaconChain,
   attestationOrBytes: AttestationOrBytes,
-  /** Optional, to allow verifying attestations through API with unknown subnet */
   subnet: number | null,
   prioritizeBls = false
 ): Promise<AttestationValidationResult> {
+  const phase0Result = await validateGossipAttestationNoSignatureCheck(fork, chain, attestationOrBytes, subnet);
+  const {attestation, signatureSet, validatorIndex} = phase0Result;
+  const isValid = await chain.bls.verifySignatureSets([signatureSet], {batchable: true, priority: prioritizeBls});
+
+  if (isValid) {
+    const targetEpoch = attestation.data.target.epoch;
+    chain.seenAttesters.add(targetEpoch, validatorIndex);
+    return phase0Result;
+  } else {
+    throw new AttestationError(GossipAction.IGNORE, {
+      code: AttestationErrorCode.INVALID_SIGNATURE,
+    });
+  }
+}
+
+/**
+ * Only deserialize the attestation if needed, use the cached AttestationData instead
+ * This is to avoid deserializing similar attestation multiple times which could help the gc
+ */
+async function validateGossipAttestationNoSignatureCheck(
+  fork: ForkName,
+  chain: IBeaconChain,
+  attestationOrBytes: AttestationOrBytes,
+  /** Optional, to allow verifying attestations through API with unknown subnet */
+  subnet: number | null
+): Promise<Phase0Result> {
   // Do checks in this order:
   // - do early checks (w/o indexed attestation)
   // - > obtain indexed attestation and committes per slot
@@ -105,11 +234,14 @@ async function validateAttestation(
   let attestationOrCache:
     | {attestation: phase0.Attestation; cache: null}
     | {attestation: null; cache: AttestationDataCacheEntry; serializedData: Uint8Array};
-  let attDataBase64: AttDataBase64 | null;
+  let attDataBase64: AttDataBase64 | null = null;
   if (attestationOrBytes.serializedData) {
     // gossip
-    attDataBase64 = getAttDataBase64FromAttestationSerialized(attestationOrBytes.serializedData);
     const attSlot = attestationOrBytes.attSlot;
+    // for old LIFO linear gossip queue we don't have attDataBase64
+    // for indexed gossip queue we have attDataBase64
+    attDataBase64 =
+      attestationOrBytes.attDataBase64 ?? getAttDataBase64FromAttestationSerialized(attestationOrBytes.serializedData);
     const cachedAttData = attDataBase64 !== null ? chain.seenAttestationDatas.get(attSlot, attDataBase64) : null;
     if (cachedAttData === null) {
       const attestation = sszDeserializeAttestation(attestationOrBytes.serializedData);
@@ -263,7 +395,7 @@ async function validateAttestation(
 
   // [REJECT] The signature of attestation is valid.
   const attestingIndices = [validatorIndex];
-  let signatureSet: ISignatureSet;
+  let signatureSet: SingleSignatureSet;
   let attDataRootHex: RootHex;
   const signature = attestationOrCache.attestation
     ? attestationOrCache.attestation.signature
@@ -304,24 +436,7 @@ async function validateAttestation(
     }
   }
 
-  if (!(await chain.bls.verifySignatureSets([signatureSet], {batchable: true, priority: prioritizeBls}))) {
-    throw new AttestationError(GossipAction.REJECT, {code: AttestationErrorCode.INVALID_SIGNATURE});
-  }
-
-  // Now that the attestation has been fully verified, store that we have received a valid attestation from this validator.
-  //
-  // It's important to double check that the attestation still hasn't been observed, since
-  // there can be a race-condition if we receive two attestations at the same time and
-  // process them in different threads.
-  if (chain.seenAttesters.isKnown(targetEpoch, validatorIndex)) {
-    throw new AttestationError(GossipAction.IGNORE, {
-      code: AttestationErrorCode.ATTESTATION_ALREADY_KNOWN,
-      targetEpoch,
-      validatorIndex,
-    });
-  }
-
-  chain.seenAttesters.add(targetEpoch, validatorIndex);
+  // no signature check, leave that for phase1
 
   const indexedAttestation: phase0.IndexedAttestation = {
     attestingIndices,
@@ -336,7 +451,7 @@ async function validateAttestation(
         data: attData,
         signature,
       };
-  return {attestation, indexedAttestation, subnet: expectedSubnet, attDataRootHex};
+  return {attestation, indexedAttestation, subnet: expectedSubnet, attDataRootHex, signatureSet, validatorIndex};
 }
 
 /**

packages/beacon-node/src/metrics/metrics/lodestar.ts

@@ -38,9 +38,9 @@ export function createLodestarMetrics(
         help: "Count of total gossip validation queue length",
         labelNames: ["topic"],
       }),
-      dropRatio: register.gauge<"topic">({
-        name: "lodestar_gossip_validation_queue_current_drop_ratio",
-        help: "Current drop ratio of gossip validation queue",
+      keySize: register.gauge<"topic">({
+        name: "lodestar_gossip_validation_queue_key_size",
+        help: "Count of total gossip validation queue key size",
         labelNames: ["topic"],
       }),
       droppedJobs: register.gauge<"topic">({
@@ -575,6 +575,15 @@ export function createLodestarMetrics(
         labelNames: ["caller"],
         buckets: [0, 1, 2, 4, 8, 16, 32, 64],
       }),
+      attestationBatchHistogram: register.histogram({
+        name: "lodestar_gossip_attestation_verified_in_batch_histogram",
+        help: "Number of attestations verified in batch",
+        buckets: [1, 2, 4, 8, 16, 32, 64, 128],
+      }),
+      attestationNonBatchCount: register.gauge({
+        name: "lodestar_gossip_attestation_verified_non_batch_count",
+        help: "Count of attestations NOT verified in batch",
+      }),
     },
 
     // Gossip block