Mysql slow log files is filled with slow queries. I used percona toolkit(pt-query-digest) to analyze them, and found the most used query that take very long is just a simple select with where clause using the primary key
the table has 2 500 000 rows and the primary key is a varchar(255). when I run the query within the mysql command line, it's very fast.
any idea where I can look to determine why the query is so slow( at 95% takes up to 9s to run).