From edef17e41da2219206addb336b6887e4adc24155 Mon Sep 17 00:00:00 2001
From: terence <terence@prysmaticlabs.com>
Date: Thu, 4 Dec 2025 16:28:02 -0500
Subject: [PATCH] Add arrival latency tracking for data column sidecars
 (#16099)

We have this for blob sidecars but not for data columns
---
 beacon-chain/sync/metrics.go                    | 6 ++++++
 beacon-chain/sync/validate_data_column.go       | 1 +
 changelog/terence_data-column-arrival-metric.md | 2 ++
 3 files changed, 9 insertions(+)
 create mode 100644 changelog/terence_data-column-arrival-metric.md

diff --git a/beacon-chain/sync/metrics.go b/beacon-chain/sync/metrics.go
index 666bd65346..7acfab0f5d 100644
--- a/beacon-chain/sync/metrics.go
+++ b/beacon-chain/sync/metrics.go
@@ -157,6 +157,12 @@ var (
 			Help: "Time for gossiped blob sidecars to arrive",
 		},
 	)
+	dataColumnSidecarArrivalGossipSummary = promauto.NewSummary(
+		prometheus.SummaryOpts{
+			Name: "gossip_data_column_sidecar_arrival_milliseconds",
+			Help: "Time for gossiped data column sidecars to arrive",
+		},
+	)
 	blobSidecarVerificationGossipSummary = promauto.NewSummary(
 		prometheus.SummaryOpts{
 			Name: "gossip_blob_sidecar_verification_milliseconds",
diff --git a/beacon-chain/sync/validate_data_column.go b/beacon-chain/sync/validate_data_column.go
index 13cc1f725d..2e3695d009 100644
--- a/beacon-chain/sync/validate_data_column.go
+++ b/beacon-chain/sync/validate_data_column.go
@@ -191,6 +191,7 @@ func (s *Service) validateDataColumn(ctx context.Context, pid peer.ID, msg *pubs
 
 	sinceSlotStartTime := receivedTime.Sub(startTime)
 	validationTime := s.cfg.clock.Now().Sub(receivedTime)
+	dataColumnSidecarArrivalGossipSummary.Observe(float64(sinceSlotStartTime.Milliseconds()))
 	dataColumnSidecarVerificationGossipHistogram.Observe(float64(validationTime.Milliseconds()))
 
 	peerGossipScore := s.cfg.p2p.Peers().Scorers().GossipScorer().Score(pid)
diff --git a/changelog/terence_data-column-arrival-metric.md b/changelog/terence_data-column-arrival-metric.md
new file mode 100644
index 0000000000..1f87724e73
--- /dev/null
+++ b/changelog/terence_data-column-arrival-metric.md
@@ -0,0 +1,2 @@
+### Added
+- prometheus summary `gossip_data_column_sidecar_arrival_milliseconds` to track data column sidecar arrival latency since slot start.