reduce max stmt length

session-dealer/mysql/const.go

@@ -96,7 +96,7 @@ const (
 // See https://dev.mysql.com/doc/refman/5.7/en/identifiers.html
 const (
 	// MaxMysqlPacketLen is the max packet payload length.
-	MaxMysqlPacketLen = 4 * 1024 * 1024
+	MaxMysqlPacketLen = 1 * 1024 * 1024
 )
 
 const (

session-dealer/mysql/session.go

@@ -115,7 +115,6 @@ func (ms *MysqlSession) checkFinish() bool {
 	}
 
 	checkNode := ms.coverRanges.head.next
-
 	if checkNode.end - checkNode.begin == int64(len(ms.cachedStmtBytes)) {
 		return true
 	}