diff --git a/lib/filestream/filestream.go b/lib/filestream/filestream.go
index f4c0d790f..9fbe35872 100644
--- a/lib/filestream/filestream.go
+++ b/lib/filestream/filestream.go
@@ -254,11 +254,17 @@ func (w *Writer) Write(p []byte) (int, error) {
 }
 
 // MustFlush flushes all the buffered data to file.
-func (w *Writer) MustFlush() {
+//
+// if isSync is true, then the flushed data is fsynced to the underlying storage.
+func (w *Writer) MustFlush(isSync bool) {
 	if err := w.bw.Flush(); err != nil {
 		logger.Panicf("FATAL: cannot flush buffered data to file %q: %s", w.f.Name(), err)
 	}
-	// Do not call w.f.Sync() for performance reasons.
+	if isSync {
+		if err := w.f.Sync(); err != nil {
+			logger.Panicf("FATAL: cannot fsync data to the underlying storage for file %q: %s", w.f.Name(), err)
+		}
+	}
 }
 
 type statWriter struct {
diff --git a/lib/persistentqueue/persistentqueue.go b/lib/persistentqueue/persistentqueue.go
index 72b63ab40..c003a3507 100644
--- a/lib/persistentqueue/persistentqueue.go
+++ b/lib/persistentqueue/persistentqueue.go
@@ -546,7 +546,7 @@ func (q *Queue) write(buf []byte) error {
 func (q *Queue) readFull(buf []byte) error {
 	bufLen := uint64(len(buf))
 	if q.readerOffset+bufLen > q.writerFlushedOffset {
-		q.writer.MustFlush()
+		q.writer.MustFlush(false)
 		q.writerFlushedOffset = q.writerOffset
 	}
 	n, err := io.ReadFull(q.reader, buf)
@@ -567,8 +567,7 @@ func (q *Queue) flushMetainfoIfNeededLocked(flushData bool) error {
 		return nil
 	}
 	if flushData {
-		q.writer.MustFlush()
-		fs.MustSyncPath(q.writerPath)
+		q.writer.MustFlush(true)
 	}
 	if err := q.flushMetainfoLocked(); err != nil {
 		return fmt.Errorf("cannot flush metainfo: %w", err)