From 9ab7c24e5a6172a0d134ed9f4df5112c39865343 Mon Sep 17 00:00:00 2001
From: Michael Sproul <michael@sigmaprime.io>
Date: Tue, 29 Mar 2022 16:37:30 +1100
Subject: [PATCH] Add metric for reward cache build time

---
 beacon_node/operation_pool/src/lib.rs     | 2 ++
 beacon_node/operation_pool/src/metrics.rs | 4 ++++
 2 files changed, 6 insertions(+)

diff --git a/beacon_node/operation_pool/src/lib.rs b/beacon_node/operation_pool/src/lib.rs
index 4135f1ae81..dd547017d7 100644
--- a/beacon_node/operation_pool/src/lib.rs
+++ b/beacon_node/operation_pool/src/lib.rs
@@ -303,9 +303,11 @@ impl<T: EthSpec> OperationPool<T> {
             .map_err(OpPoolError::GetAttestationsTotalBalanceError)?;
 
         // Update the reward cache.
+        let reward_timer = metrics::start_timer(&metrics::BUILD_REWARD_CACHE_TIME);
         let mut reward_cache = self.reward_cache.write();
         reward_cache.update(state)?;
         let reward_cache = RwLockWriteGuard::downgrade(reward_cache);
+        drop(reward_timer);
 
         // Split attestations for the previous & current epochs, so that we
         // can optimise them individually in parallel.
diff --git a/beacon_node/operation_pool/src/metrics.rs b/beacon_node/operation_pool/src/metrics.rs
index 3fa5208a3d..6fd8567cef 100644
--- a/beacon_node/operation_pool/src/metrics.rs
+++ b/beacon_node/operation_pool/src/metrics.rs
@@ -3,6 +3,10 @@ use lazy_static::lazy_static;
 pub use lighthouse_metrics::*;
 
 lazy_static! {
+    pub static ref BUILD_REWARD_CACHE_TIME: Result<Histogram> = try_create_histogram(
+        "op_pool_build_reward_cache_time",
+        "Time to build the reward cache before packing attestations"
+    );
     pub static ref ATTESTATION_PREV_EPOCH_PACKING_TIME: Result<Histogram> = try_create_histogram(
         "op_pool_attestation_prev_epoch_packing_time",
         "Time to pack previous epoch attestations"