MySQL export causes swap alarm

A server recently reported swap <60% every early morning.

LocateCodeAnd export some database data to the file. The size is about 1 GB.

 
String exportcmd = "/usr/bin/MySQL -- safe-update = false-h" + dbhost + "-P" + dbport + "-U" + dbusername + "-P" + dbpassword + "-- default-character-set = utf8" + database + "-e \" "+ export_ SQL +" \ ">" + configuration. getiosfilepath ();
 

Memory usage increases and cannot be released for a period of time due to each export. The -- quick parameter is added.

If you have problems due to insufficient memory for large result sets, use the -- quick option. This forces MySQL to retrieve results from the server
Row at a time rather than retrieving the entire result set and buffering it in memory before displaying it. This is done by returning the result set
Using the mysql_use_result () c api function in the Client/Server library rather than mysql_store_result ().