improve metrics and tracing

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

stats.go

@@ -0,0 +1,57 @@
+package redis
+
+import (
+	"time"
+
+	"github.com/redis/go-redis/v9"
+)
+
+var (
+	PoolHitsTotal        = "pool_hits_total"
+	PoolMissesTotal      = "pool_misses_total"
+	PoolTimeoutTotal     = "pool_timeout_total"
+	PoolConnTotalCurrent = "pool_conn_total_current"
+	PoolConnIdleCurrent  = "pool_conn_idle_current"
+	PoolConnStaleTotal   = "pool_conn_stale_total"
+
+	meterRequestTotal               = "request_total"
+	meterRequestLatencyMicroseconds = "latency_microseconds"
+	meterRequestDurationSeconds     = "request_duration_seconds"
+)
+
+type Statser interface {
+	PoolStats() *redis.PoolStats
+}
+
+func (r *Store) statsMeter() {
+	var st Statser
+
+	if r.cli.Client != nil {
+		st = r.cli.Client
+	} else if r.cli.ClusterClient != nil {
+		st = r.cli.ClusterClient
+	} else {
+		return
+	}
+
+	go func() {
+		ticker := time.NewTicker(DefaultMeterStatsInterval)
+		defer ticker.Stop()
+
+		for {
+			select {
+			case <-ticker.C:
+				if st == nil {
+					return
+				}
+				stats := st.PoolStats()
+				r.opts.Meter.Counter(PoolHitsTotal).Set(uint64(stats.Hits))
+				r.opts.Meter.Counter(PoolMissesTotal).Set(uint64(stats.Misses))
+				r.opts.Meter.Counter(PoolTimeoutTotal).Set(uint64(stats.Timeouts))
+				r.opts.Meter.Counter(PoolConnTotalCurrent).Set(uint64(stats.TotalConns))
+				r.opts.Meter.Counter(PoolConnIdleCurrent).Set(uint64(stats.IdleConns))
+				r.opts.Meter.Counter(PoolConnStaleTotal).Set(uint64(stats.StaleConns))
+			}
+		}
+	}()
+}