tidb: session retry metrics (pingcap#2419)

niuhw · Jan 9, 2017 · 677a85b · 677a85b
1 parent 962cd0c
commit 677a85b
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Showing 3 changed files with 12 additions and 3 deletions.
diff --git a/domain/metrics.go b/domain/metrics.go
@@ -21,15 +21,15 @@ var (
 	loadSchemaCounter = prometheus.NewCounterVec(
 		prometheus.CounterOpts{
 			Namespace: "tidb",
-			Subsystem: "domain",
+			Subsystem: "server",
 			Name:      "load_schema_total",
 			Help:      "Counter of load schema",
 		}, []string{"type"})
 
 	loadSchemaDuration = prometheus.NewHistogram(
 		prometheus.HistogramOpts{
 			Namespace: "tidb",
-			Subsystem: "domain",
+			Subsystem: "server",
 			Name:      "load_schema_duration",
 			Help:      "Bucketed histogram of processing time (s) in load schema.",
 			Buckets:   prometheus.ExponentialBuckets(0.001, 2, 15),

diff --git a/metrics.go b/metrics.go
@@ -49,6 +49,14 @@ var (
 			Name:      "schema_lease_error_counter",
 			Help:      "Counter of schema lease error",
 		}, []string{"type"})
+	sessionRetry = prometheus.NewHistogram(
+		prometheus.HistogramOpts{
+			Namespace: "tidb",
+			Subsystem: "server",
+			Name:      "session_retry",
+			Help:      "Bucketed histogram of session retry count.",
+			Buckets:   prometheus.LinearBuckets(0, 1, 10),
+		})
 )
 
 func init() {

diff --git a/session.go b/session.go
@@ -295,12 +295,13 @@ func (s *session) Retry() error {
 		return errors.Errorf("can not retry select for update statement")
 	}
 	s.sessionVars.RetryInfo.Retrying = true
+	retryCnt := 0
 	defer func() {
 		s.sessionVars.RetryInfo.Retrying = false
+		sessionRetry.Observe(float64(retryCnt))
 	}()
 	nh := getHistory(s)
 	var err error
-	retryCnt := 0
 	for {
 		s.prepareTxnCtx()
 		s.sessionVars.RetryInfo.ResetOffset()