slow server when page have mysql

slow server when page have mysql


my server now works very fast in non mysql requests , example:
http://download.saqafa.com/
but when it come to more mysql requests it be very slow and take more time
to load , i don't know the reason , my server is I5 with 12 GB rams
example of slow page :
http://www.saqafa.com/article/8434