feat: track participants of produced aggregates (#5750)

* Track participants of produced aggregates * Add benchmark * Fix typo in participants --------- Co-authored-by: Nico Flaig <[email protected]>
ChainSafe · Jul 14, 2023 · de00b80 · de00b80
1 parent 4b5280d
commit de00b80
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Showing 4 changed files with 49 additions and 3 deletions.
diff --git a/packages/beacon-node/src/api/impl/validator/index.ts b/packages/beacon-node/src/api/impl/validator/index.ts
@@ -374,6 +374,11 @@ export function getValidatorApi({
 
       const contribution = chain.syncCommitteeMessagePool.getContribution(subcommitteeIndex, slot, beaconBlockRoot);
       if (!contribution) throw new ApiError(500, "No contribution available");
+
+      metrics?.production.producedSyncContributionParticipants.observe(
+        contribution.aggregationBits.getTrueBitIndexes().length
+      );
+
       return {data: contribution};
     },
 
@@ -538,6 +543,9 @@ export function getValidatorApi({
 
       await waitForSlot(slot); // Must never request for a future slot > currentSlot
 
+      const aggregate = chain.attestationPool.getAggregate(slot, attestationDataRoot);
+      metrics?.production.producedAggregateParticipants.observe(aggregate.aggregationBits.getTrueBitIndexes().length);
+
       return {
         data: chain.attestationPool.getAggregate(slot, attestationDataRoot),
       };

diff --git a/packages/beacon-node/src/chain/produceBlock/produceBlockBody.ts b/packages/beacon-node/src/chain/produceBlock/produceBlockBody.ts
@@ -130,10 +130,11 @@ export async function produceBlockBody<T extends BlockType>(
   const blockEpoch = computeEpochAtSlot(blockSlot);
 
   if (blockEpoch >= this.config.ALTAIR_FORK_EPOCH) {
-    (blockBody as altair.BeaconBlockBody).syncAggregate = this.syncContributionAndProofPool.getAggregate(
-      parentSlot,
-      parentBlockRoot
+    const syncAggregate = this.syncContributionAndProofPool.getAggregate(parentSlot, parentBlockRoot);
+    this.metrics?.production.producedSyncAggregateParticipants.observe(
+      syncAggregate.syncCommitteeBits.getTrueBitIndexes().length
     );
+    (blockBody as altair.BeaconBlockBody).syncAggregate = syncAggregate;
   }
 
   const fork = currentState.config.getForkName(blockSlot);

diff --git a/packages/beacon-node/src/metrics/metrics/lodestar.ts b/packages/beacon-node/src/metrics/metrics/lodestar.ts
@@ -221,6 +221,30 @@ export function createLodestarMetrics(
       }),
     },
 
+    production: {
+      producedAggregateParticipants: register.histogram({
+        name: "lodestar_produced_aggregate_participants",
+        help: "API impl produced aggregates histogram of participants",
+        // We care more about tracking low quality aggregates with low participation
+        // Max committee sizes are: 0.5e6 vc: 244, 1e6 vc: 488
+        buckets: [1, 5, 20, 50, 100, 200, 400],
+      }),
+      producedSyncContributionParticipants: register.histogram({
+        name: "lodestar_produced_sync_contribution_participants",
+        help: "API impl produced sync contribution histogram of participants",
+        // We care more about tracking low quality aggregates with low participation
+        // Max committee sizes fixed to 512/4 = 128
+        buckets: [1, 5, 20, 50, 128],
+      }),
+      producedSyncAggregateParticipants: register.histogram({
+        name: "lodestar_produced_sync_aggregate_participants",
+        help: "API impl produced sync aggregate histogram of participants",
+        // We care more about tracking low quality aggregates with low participation
+        // Max committee sizes fixed to 512
+        buckets: [1, 5, 20, 50, 100, 200, 512],
+      }),
+    },
+
     // Beacon state transition metrics
 
     epochTransitionTime: register.histogram({

diff --git a/packages/beacon-node/test/perf/util/bitArray.test.ts b/packages/beacon-node/test/perf/util/bitArray.test.ts
@@ -1,3 +1,4 @@
+import crypto from "node:crypto";
 import {itBench, setBenchOpts} from "@dapplion/benchmark";
 import {BitArray} from "@chainsafe/ssz";
 import {intersectUint8Arrays} from "../../../src/util/bitArray.js";
@@ -45,6 +46,18 @@ describe("Intersect BitArray vs Array+Set", () => {
   }
 });
 
+describe("BitArray.trueBitCount", () => {
+  for (const bitLen of [128, 248, 512]) {
+    itBench({
+      id: `bitArray.getTrueBitIndexes() bitLen ${bitLen}`,
+      beforeEach: () => new BitArray(crypto.randomBytes(Math.ceil(bitLen / 8)), bitLen),
+      fn: (bitArray) => {
+        bitArray.getTrueBitIndexes().length;
+      },
+    });
+  }
+});
+
 function linspace(start: number, end: number, step: number): number[] {
   const arr: number[] = [];
   for (let i = start; i < end; i += step) {