Audit mysql query slow.
1. start slow log.
Two method:
(1)edit my.cnf ,add text as belows to [mysqld].
#if long_query_time=0, all queries will be saved to log file
long_query_time=1
#create the log file and give the log file mysql access authority by chown mysql.mysql file_name
log-slow-queries[=file_name]
(2)start mysqld with the --log-slow-queries[=file_name] option.
2.analyze slow log
I have fond two method to analyze the slow log.
(1)mysqldumpslow which is supplied by mysql.
Use this command we can see summarizes of the log file.
mysqldumpslow file_name //eg: mysqldumpslow /opt/test/mysql_slow.log
(2)Myprofi.http://myprofi.sourceforge.net/.
MyProfi is a command line tool that parses mysql query log and outputs statistics of most frequently used queries,
sorting them by number of times they appear in a log file
Down the source code from http://myprofi.sourceforge.net/ ,and copy parser.php to centos. Use follow command to analyze the log
//show all slow queries.
php parser.php -slow /opt/test/mysql.log
//show top N slow queries.
php parser.php -top N -slow /opt/test/mysql.log
//only show select slow queries, we can also add other options such as update ,insert ,delete.
php parser.php -top 10 -type "select" -slow /opt/test/mysql.log
