diff --git a/app/vminsert/netstorage/netstorage.go b/app/vminsert/netstorage/netstorage.go
index 62b22ed7b8..76b89f6de8 100644
--- a/app/vminsert/netstorage/netstorage.go
+++ b/app/vminsert/netstorage/netstorage.go
@@ -107,9 +107,6 @@ func (sn *storageNode) flushBufLocked() error {
 }
 
 func (sn *storageNode) sendBufLocked(buf []byte) error {
-	// sizeBuf guarantees that the rows batch will be either fully
-	// read or fully discarded on the vmstorage side.
-	// sizeBuf is used for read optimization in vmstorage.
 	if sn.bc == nil {
 		if err := sn.dial(); err != nil {
 			return fmt.Errorf("cannot dial %q: %s", sn.dialer.Addr(), err)
@@ -118,11 +115,19 @@ func (sn *storageNode) sendBufLocked(buf []byte) error {
 	if len(buf) == 0 {
 		return nil
 	}
-	deadline := time.Now().Add(30 * time.Second)
+	timeoutSeconds := len(buf) / 1e6
+	if timeoutSeconds < 10 {
+		timeoutSeconds = 10
+	}
+	timeout := time.Duration(timeoutSeconds) * time.Second
+	deadline := time.Now().Add(timeout)
 	if err := sn.bc.SetWriteDeadline(deadline); err != nil {
 		sn.closeBrokenConn()
 		return fmt.Errorf("cannot set write deadline to %s: %s", deadline, err)
 	}
+	// sizeBuf guarantees that the rows batch will be either fully
+	// read or fully discarded on the vmstorage side.
+	// sizeBuf is used for read optimization in vmstorage.
 	sn.sizeBuf = encoding.MarshalUint64(sn.sizeBuf[:0], uint64(len(buf)))
 	if _, err := sn.bc.Write(sn.sizeBuf); err != nil {
 		sn.closeBrokenConn()