Posts tagged slow-query-log

mysql slow query log

posted on 2016-11-07 10:30

To enable mysql's slow query log:

show variables like '%query%';
show variables like '%slow%';
set global slow_query_log = 'on';
show variables like '%slow%';
flush logs; 

set global long_query_time = 1;
set global long_query_time = 5;
flush logs;

Look up what is set for slow_query_log_file, and try doing a tail -f on it in another window. That way you have instant feedback wether your settings work.

If you don't immeaditly see output, try lowering long_query_time, measured in seconds. Try flush logs; in case you see nothing and slowquery threshold is already set to 1 second.

Also set global log_queries_not_using_indexes = on; might help a lot.

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