From fc4ba7b2fc27a9c37feb2105e4e6f8f73aedb4c9 Mon Sep 17 00:00:00 2001
From: Tuyen Nguyen <vutuyen2636@gmail.com>
Date: Mon, 8 Jan 2024 10:21:40 +0700
Subject: [PATCH] feat: track prepare next epoch time

---
 packages/beacon-node/src/chain/prepareNextSlot.ts    | 5 +++++
 packages/beacon-node/src/metrics/metrics/lodestar.ts | 5 +++++
 2 files changed, 10 insertions(+)

diff --git a/packages/beacon-node/src/chain/prepareNextSlot.ts b/packages/beacon-node/src/chain/prepareNextSlot.ts
index e2bffd5bc8c6..5bce756c0d13 100644
--- a/packages/beacon-node/src/chain/prepareNextSlot.ts
+++ b/packages/beacon-node/src/chain/prepareNextSlot.ts
@@ -97,6 +97,9 @@ export class PrepareNextSlotScheduler {
         headRoot,
         isEpochTransition,
       });
+      const lodestarPrecomputeEpochTransitionTimer = isEpochTransition
+        ? this.metrics?.precomputeNextEpochTransition.duration.startTimer()
+        : null;
       // No need to wait for this or the clock drift
       // Pre Bellatrix: we only do precompute state transition for the last slot of epoch
       // For Bellatrix, we always do the `processSlots()` to prepare payload for the next slot
@@ -133,6 +136,8 @@ export class PrepareNextSlotScheduler {
           prepareSlot,
           previousHits,
         });
+
+        lodestarPrecomputeEpochTransitionTimer?.();
       }
 
       if (isExecutionStateType(prepareState)) {
diff --git a/packages/beacon-node/src/metrics/metrics/lodestar.ts b/packages/beacon-node/src/metrics/metrics/lodestar.ts
index ea2251b3dce5..dc96321b3885 100644
--- a/packages/beacon-node/src/metrics/metrics/lodestar.ts
+++ b/packages/beacon-node/src/metrics/metrics/lodestar.ts
@@ -1298,6 +1298,11 @@ export function createLodestarMetrics(
         name: "lodestar_precompute_next_epoch_transition_waste_total",
         help: "Total number of precomputing next epoch transition wasted",
       }),
+      duration: register.histogram({
+        name: "lodestar_precompute_next_epoch_transition_duration_seconds",
+        help: "Duration of precomputeNextEpochTransition at lodestar side",
+        buckets: [1, 2, 3, 4, 8],
+      }),
     },
 
     // reprocess attestations