diff --git a/chunkreader.go b/chunkreader.go
index 36304fd5..afea1c52 100644
--- a/chunkreader.go
+++ b/chunkreader.go
@@ -39,7 +39,11 @@ func New(r io.Reader) *ChunkReader {
 // NewConfig creates and a new ChunkReader for r configured by config.
 func NewConfig(r io.Reader, config Config) (*ChunkReader, error) {
 	if config.MinBufLen == 0 {
-		config.MinBufLen = 4096
+		// By historical reasons Postgres currently has 8KB send buffer inside,
+		// so here we want to have at least the same size buffer.
+		// @see https://github.com/postgres/postgres/blob/249d64999615802752940e017ee5166e726bc7cd/src/backend/libpq/pqcomm.c#L134
+		// @see https://www.postgresql.org/message-id/0cdc5485-cb3c-5e16-4a46-e3b2f7a41322%40ya.ru
+		config.MinBufLen = 8192
 	}
 
 	return &ChunkReader{