Prepare for extracting EtcdHelper interface

pkg/tools/metrics/metrics.go

@@ -0,0 +1,104 @@
+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package metrics
+
+import (
+	"sync"
+	"time"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+var (
+	cacheHitCounter = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Name: "etcd_helper_cache_hit_count",
+			Help: "Counter of etcd helper cache hits.",
+		},
+	)
+	cacheMissCounter = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Name: "etcd_helper_cache_miss_count",
+			Help: "Counter of etcd helper cache miss.",
+		},
+	)
+	cacheEntryCounter = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Name: "etcd_helper_cache_entry_count",
+			Help: "Counter of etcd helper cache entries. This can be different from etcd_helper_cache_miss_count " +
+				"because two concurrent threads can miss the cache and generate the same entry twice.",
+		},
+	)
+	cacheGetLatency = prometheus.NewSummary(
+		prometheus.SummaryOpts{
+			Name: "etcd_request_cache_get_latencies_summary",
+			Help: "Latency in microseconds of getting an object from etcd cache",
+		},
+	)
+	cacheAddLatency = prometheus.NewSummary(
+		prometheus.SummaryOpts{
+			Name: "etcd_request_cache_add_latencies_summary",
+			Help: "Latency in microseconds of adding an object to etcd cache",
+		},
+	)
+	etcdRequestLatenciesSummary = prometheus.NewSummaryVec(
+		prometheus.SummaryOpts{
+			Name: "etcd_request_latencies_summary",
+			Help: "Etcd request latency summary in microseconds for each operation and object type.",
+		},
+		[]string{"operation", "type"},
+	)
+)
+
+var registerMetrics sync.Once
+
+// Register all metrics.
+func Register() {
+	// Register the metrics.
+	registerMetrics.Do(func() {
+		prometheus.MustRegister(cacheHitCounter)
+		prometheus.MustRegister(cacheMissCounter)
+		prometheus.MustRegister(cacheEntryCounter)
+		prometheus.MustRegister(cacheAddLatency)
+		prometheus.MustRegister(cacheGetLatency)
+		prometheus.MustRegister(etcdRequestLatenciesSummary)
+	})
+}
+
+func RecordEtcdRequestLatency(verb, resource string, startTime time.Time) {
+	etcdRequestLatenciesSummary.WithLabelValues(verb, resource).Observe(float64(time.Since(startTime) / time.Microsecond))
+}
+
+func ObserveGetCache(startTime time.Time) {
+	cacheGetLatency.Observe(float64(time.Since(startTime) / time.Microsecond))
+}
+
+func ObserveAddCache(startTime time.Time) {
+	cacheAddLatency.Observe(float64(time.Since(startTime) / time.Microsecond))
+}
+
+func ObserveCacheHit() {
+	cacheHitCounter.Inc()
+}
+
+func ObserveCacheMiss() {
+	cacheMissCounter.Inc()
+}
+
+func ObserveNewEntry() {
+	cacheEntryCounter.Inc()
+}