@@ -23,1 +23,4 @@
 	flushCh chan *objectSDK.Object
+	// scheduled4Flush contains objects scheduled for flush via flushCh
+	// helps to avoid multiple flushing of one object
+	scheduled4Flush    map[oid.Address]any

@@ -38,0 +58,4 @@
+		if kv.StreamDone {
+			return nil
+		}
+		if c.scheduled >= flushBatchSize {

@@ -38,0 +62,4 @@
+			c.cancel()
+			return nil
+		}
+		if got, want := len(kv.Key), len(cid.ID{})+len(oid.ID{}); got != want {

@@ -38,0 +70,4 @@
+		c.processed++
+		obj := objectSDK.New()
+		var val []byte
+		val = append(val, kv.Value...)

@@ -38,0 +74,4 @@
+		if err = obj.Unmarshal(val); err == nil {
+			addr := objectCore.AddressOf(obj)
+			c.cache.scheduled4FlushMtx.RLock()
+			_, ok := c.cache.scheduled4Flush[addr]

@@ -38,0 +91,4 @@
+				return nil
+			}
+		} else {
+			c.cache.log.Debug(fmt.Sprintf("error unmarshal: %s", err))

@@ -129,3 +146,1 @@
-				c.modeMtx.RUnlock()
-				return
-			}
+		ctx, cancel := context.WithCancel(context.TODO())

@@ -134,2 +151,2 @@
-		if count == 0 {
-			c.modeMtx.RUnlock()
+		stream := c.db.NewStream()
+		// Logic within Send method can expect single threaded execution.

@@ -136,0 +151,4 @@
+		stream := c.db.NewStream()
+		// Logic within Send method can expect single threaded execution.
+		stream.Send = coll.Send
+		if err := stream.Orchestrate(ctx); err != nil {

@@ -141,3 +162,2 @@
 		c.log.Debug(logs.WritecacheTriedToFlushItemsFromWritecache,
-			zap.Int("count", count),
-			zap.String("start", base58.Encode(lastKey[:])))
+			zap.Int("scheduled", coll.scheduled), zap.Int("processed", coll.processed))

@@ -136,0 +153,4 @@
+				"error during flushing object from wc: %s", err))
+		}
+		c.modeMtx.RUnlock()
+		if coll.scheduled == 0 {