sleep processes

[hessodreamy]

Recently I've noticed the mysql server going very slow at times. At such times i've run show full processlist and there's been one or two processes with a status sleep and time being anything up to about 40 seconds.

What are theses proceses? Are they read/write processes waiting for their turn? Is it possible that further queries coming are just stuck in a non-moving queue?

Any ideas?

 

[hessodreamy]

by the way i'm connecting from php using mysql_connect. I think that's non-persistent!