[#1335] writecache: Change DB engine to Pebble

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

pkg/local_object_storage/writecache/put.go

@@ -2,13 +2,14 @@ package writecache
 
 import (
 	"context"
+	"errors"
 	"time"
 
 	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/blobstor/common"
 	storagelog "git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/internal/log"
 	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/internal/metaerr"
 	"git.frostfs.info/TrueCloudLab/frostfs-observability/tracing"
-	"go.etcd.io/bbolt"
+	"github.com/cockroachdb/pebble"
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/trace"
 )
@@ -80,28 +81,36 @@ func (c *cache) putSmall(obj objectInfo) error {
 		return ErrOutOfSpace
 	}
 
-	var newRecord bool
-	err := c.db.Batch(func(tx *bbolt.Tx) error {
-		b := tx.Bucket(defaultBucket)
-		key := []byte(obj.addr)
-		newRecord = b.Get(key) == nil
-		if newRecord {
-			return b.Put(key, obj.data)
-		}
-		return nil
-	})
+	c.dbEditLocker.Lock(obj.addr)
+	defer func() {
+		c.dbEditLocker.Unlock(obj.addr)
+	}()
+	newRecord := true
+	dbKey := []byte(obj.addr)
+	data, closer, err := c.db.Get(dbKey)
 	if err == nil {
-		storagelog.Write(c.log,
-			storagelog.AddressField(obj.addr),
-			storagelog.StorageTypeField(wcStorageType),
-			storagelog.OpField("db PUT"),
-		)
-		if newRecord {
-			c.objCounters.cDB.Add(1)
-			c.estimateCacheSize()
+		newRecord = len(data) == 0
+		err = closer.Close()
+	}
+	if err != nil && !errors.Is(err, pebble.ErrNotFound) {
+		return err
+	}
+	if newRecord {
+		err = c.db.Set(dbKey, obj.data, pebble.Sync)
+		if err != nil {
+			return err
 		}
 	}
-	return err
+	storagelog.Write(c.log,
+		storagelog.AddressField(obj.addr),
+		storagelog.StorageTypeField(wcStorageType),
+		storagelog.OpField("db PUT"),
+	)
+	if newRecord {
+		c.objCounters.cDB.Add(1)
+		c.estimateCacheSize()
+	}
+	return nil
 }
 
 // putBig writes object to FSTree and pushes it to the flush workers queue.