fix: enforce strict timeout for builder to provide bid (#7151)

* fix: enforce strict timeout for builder to provide bid * Use math.round
ChainSafe · Oct 15, 2024 · 5adb4ef · 5adb4ef
1 parent 4e853d6
commit 5adb4ef
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Showing 2 changed files with 11 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
@@ -89,7 +89,7 @@ import {computeSubnetForCommitteesAtSlot, getPubkeysForIndices, selectBlockProdu
 export const SYNC_TOLERANCE_EPOCHS = 1;
 
 /**
- * Cutoff time to wait for execution and builder block production apis to resolve
+ * Cutoff time to wait from start of the slot for execution and builder block production apis to resolve
  * Post this time, race execution and builder to pick whatever resolves first
  *
  * Empirically the builder block resolves in ~1.5+ seconds, and execution should resolve <1 sec.
@@ -637,7 +637,7 @@ export function getValidatorApi(
       : Promise.reject(new Error("Engine disabled"));
 
     const [builder, engine] = await resolveOrRacePromises([builderPromise, enginePromise], {
-      resolveTimeoutMs: BLOCK_PRODUCTION_RACE_CUTOFF_MS,
+      resolveTimeoutMs: Math.max(0, BLOCK_PRODUCTION_RACE_CUTOFF_MS - Math.round(chain.clock.secFromSlot(slot) * 1000)),
       raceTimeoutMs: BLOCK_PRODUCTION_RACE_TIMEOUT_MS,
       signal: controller.signal,
     });

diff --git a/packages/beacon-node/src/execution/builder/http.ts b/packages/beacon-node/src/execution/builder/http.ts
@@ -37,6 +37,12 @@ export const defaultExecutionBuilderHttpOpts: ExecutionBuilderHttpOpts = {
   timeout: 12000,
 };
 
+/**
+ * Duration given to the builder to provide a `SignedBuilderBid` before the deadline
+ * is reached, aborting the external builder flow in favor of the local build process.
+ */
+const BUILDER_PROPOSAL_DELAY_TOLERANCE = 1000;
+
 export class ExecutionBuilderHttp implements IExecutionBuilder {
   readonly api: BuilderApi;
   readonly config: ChainForkConfig;
@@ -115,7 +121,9 @@ export class ExecutionBuilderHttp implements IExecutionBuilder {
     executionPayloadValue: Wei;
     blobKzgCommitments?: deneb.BlobKzgCommitments;
   }> {
-    const signedBuilderBid = (await this.api.getHeader({slot, parentHash, proposerPubkey})).value();
+    const signedBuilderBid = (
+      await this.api.getHeader({slot, parentHash, proposerPubkey}, {timeoutMs: BUILDER_PROPOSAL_DELAY_TOLERANCE})
+    ).value();
 
     if (!signedBuilderBid) {
       throw Error("No bid received");