[#373] metabase: Add metrics

Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

pkg/local_object_storage/metabase/delete.go

@@ -5,6 +5,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"time"
 
 	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/core/object"
 	storagelog "git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/internal/log"
@@ -71,6 +72,14 @@ type referenceCounter map[string]*referenceNumber
 
 // Delete removed object records from metabase indexes.
 func (db *DB) Delete(ctx context.Context, prm DeletePrm) (DeleteRes, error) {
+	var (
+		startedAt = time.Now()
+		deleted   = false
+	)
+	defer func() {
+		db.metrics.AddMethodDuration("Delete", time.Since(startedAt), deleted)
+	}()
+
 	_, span := tracing.StartSpanFromContext(ctx, "metabase.Delete",
 		trace.WithAttributes(
 			attribute.Int("addr_count", len(prm.addrs)),
@@ -98,6 +107,7 @@ func (db *DB) Delete(ctx context.Context, prm DeletePrm) (DeleteRes, error) {
 		return err
 	})
 	if err == nil {
+		deleted = true
 		for i := range prm.addrs {
 			storagelog.Write(db.log,
 				storagelog.AddressField(prm.addrs[i]),