Merge pull request #9820 from gyuho/quota-size

*: add "etcd_server_quota_backend_bytes" metric

Author: gyuho

etcdserver/metrics.go

@@ -84,6 +84,12 @@ var (
 		Name:      "lease_expired_total",
 		Help:      "The total number of expired leases.",
 	})
+	quotaBackendBytes = prometheus.NewGauge(prometheus.GaugeOpts{
+		Namespace: "etcd",
+		Subsystem: "server",
+		Name:      "quota_backend_bytes",
+		Help:      "Current backend storage quota size in bytes.",
+	})
 	currentVersion = prometheus.NewGaugeVec(prometheus.GaugeOpts{
 		Namespace: "etcd",
 		Subsystem: "server",
@@ -104,6 +110,7 @@ func init() {
 	prometheus.MustRegister(proposalsPending)
 	prometheus.MustRegister(proposalsFailed)
 	prometheus.MustRegister(leaseExpired)
+	prometheus.MustRegister(quotaBackendBytes)
 	prometheus.MustRegister(currentVersion)
 
 	currentVersion.With(prometheus.Labels{

etcdserver/quota.go

@@ -62,6 +62,7 @@ const (
 
 func NewBackendQuota(s *EtcdServer, name string) Quota {
 	lg := s.getLogger()
+	quotaBackendBytes.Set(float64(s.Cfg.QuotaBackendBytes))
 
 	if s.Cfg.QuotaBackendBytes < 0 {
 		// disable quotas if negative
@@ -87,6 +88,7 @@ func NewBackendQuota(s *EtcdServer, name string) Quota {
 				zap.String("quota-size", humanize.Bytes(uint64(DefaultQuotaBytes))),
 			)
 		}
+		quotaBackendBytes.Set(float64(DefaultQuotaBytes))
 		return &backendQuota{s, DefaultQuotaBytes}
 	}
 

integration/metrics_test.go

@@ -20,6 +20,8 @@ import (
 	"testing"
 	"time"
 
+	"github.com/coreos/etcd/etcdserver"
+
 	pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
 	"github.com/coreos/etcd/pkg/testutil"
 )
@@ -145,3 +147,21 @@ func testMetricDbSizeDefrag(t *testing.T, name string) {
 		t.Fatalf("db size in use (%d) is expected less than db size (%d) after defrag", adiu, av)
 	}
 }
+
+func TestMetricQuotaBackendBytes(t *testing.T) {
+	defer testutil.AfterTest(t)
+	clus := NewClusterV3(t, &ClusterConfig{Size: 1})
+	defer clus.Terminate(t)
+
+	qs, err := clus.Members[0].Metric("etcd_server_quota_backend_bytes")
+	if err != nil {
+		t.Fatal(err)
+	}
+	qv, err := strconv.ParseFloat(qs, 64)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if int64(qv) != etcdserver.DefaultQuotaBytes {
+		t.Fatalf("expected %d, got %f", etcdserver.DefaultQuotaBytes, qv)
+	}
+}