Re: Slow Performance CPU not increase

[Rick James]

A guess: You have a slow query that is pounding on the disk. Find that slow query, and let's discuss how to improve it.

To assist in analyzing slow SELECTs, please provide
* SHOW CREATE TABLE tbl\G -- engine, indexes
* SHOW TABLE STATUS LIKE 'tbl'\G -- sizes
* EXPLAIN SELECT ...\G -- clues of inefficiencies
* SHOW VARIABLES LIKE '%buffer%'; -- cache size
and surround them with [ code ] and [ / code ]

You might switch over to the Performance forum; your issue is probably not MyISAM-specific.