From 37bdc34d86dccae298b9cb4fca6d8697e2877c4f Mon Sep 17 00:00:00 2001
From: tiancaiamao <tiancaiamao@gmail.com>
Date: Tue, 31 Dec 2019 16:42:38 +0800
Subject: [PATCH] metrics,store: add a metric for ttlManager to record the
 lifetime reach events

---
 metrics/metrics.go    | 1 +
 metrics/tikvclient.go | 8 ++++++++
 store/tikv/2pc.go     | 1 +
 3 files changed, 10 insertions(+)

diff --git a/metrics/metrics.go b/metrics/metrics.go
index e25c6aa6c0872..57401d1c0b879 100644
--- a/metrics/metrics.go
+++ b/metrics/metrics.go
@@ -156,4 +156,5 @@ func RegisterMetrics() {
 	prometheus.MustRegister(TiKVTxnHeartBeatHistogram)
 	prometheus.MustRegister(TiKVPessimisticLockKeysDuration)
 	prometheus.MustRegister(GRPCConnTransientFailureCounter)
+	prometheus.MustRegister(TiKVTTLLifeTimeReachCounter)
 }
diff --git a/metrics/tikvclient.go b/metrics/tikvclient.go
index 8c12c4fa384e3..c00d4027acd40 100644
--- a/metrics/tikvclient.go
+++ b/metrics/tikvclient.go
@@ -240,4 +240,12 @@ var (
 			Buckets:   prometheus.ExponentialBuckets(0.001, 2, 24), // 1ms ~ 16777s
 			Help:      "tidb txn pessimistic lock keys duration",
 		})
+
+	TiKVTTLLifeTimeReachCounter = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Namespace: "tidb",
+			Subsystem: "tikvclient",
+			Name:      "ttl_lifetime_reach_total",
+			Help:      "Counter of ttlManager live too long.",
+		})
 )
diff --git a/store/tikv/2pc.go b/store/tikv/2pc.go
index de6af63718f10..bcced34acb3a6 100644
--- a/store/tikv/2pc.go
+++ b/store/tikv/2pc.go
@@ -703,6 +703,7 @@ func (tm *ttlManager) keepAlive(c *twoPhaseCommitter) {
 				// the key will not be locked forever.
 				logutil.Logger(context.Background()).Info("ttlManager live up to its lifetime",
 					zap.Uint64("txnStartTS", c.startTS))
+				metrics.TiKVTTLLifeTimeReachCounter.Inc()
 				return
 			}