Hi all, after few days looking at some performances issues with fcgi, I found mysqltuner (https://github.com/rackerhacker/MySQLTuner-perl)
I made few changes on the mysql configuration via Virtualmin (pro) BUT I have some variables to set but I can’t do it on the virtualmin interface, like :
query_cache_limit (> 2M, or use smaller result sets)
join_buffer_size (> 128.0K, or always use indexes with joins)
tmp_table_size (> 16M)
max_heap_table_size (> 16M)
thread_cache_size (start at 4)
table_cache (> 64)
Where, on Debian Squeeze, I can change these variables, or is there is a way to change it on virtualmin ?
You can tweak some MySQL variables using Virtualmin.
To do that, go into Webmin -> Servers -> MySQL -> MySQL Server Configuration, and the variables you can tweak are on that screen.
Alternatively, for direct access to the config file so that you can edit any of the variables, you can edit /etc/mysql/my.cnf. Most of the variables you’re discussing would go under the [mysqld] section.
I’m not sure of a way to configure PHP like that… but you can solve the problem in a similar way by researching caching solutions.
Many applications support various forms of caching – memcache is one example.
If your application can be configured to use memcache, and it’s doing a lot of database lookups – that can really improve the performance you’re getting.
There’s other types of caching solutions as well, memcache is just one which caches things such as database lookups.