diff --git a/pkg/local_object_storage/writecache/flush.go b/pkg/local_object_storage/writecache/flush.go
index 3f9b36f9d..2d07d8b32 100644
--- a/pkg/local_object_storage/writecache/flush.go
+++ b/pkg/local_object_storage/writecache/flush.go
@@ -87,6 +87,9 @@ func (c *cache) pushToFlushQueue(ctx context.Context, fl *flushLimiter) {
 			}
 
 			c.modeMtx.RUnlock()
+
+			// counter changed by fstree
+			c.estimateCacheSize()
 		case <-ctx.Done():
 			return
 		}