[Dovecot] dovecot process nice value

[Daniel Watts]

My imap processes seem to all be running with a nice value of -15 (top 
priority). Is this usual? Not sure if this is a dovecot setting or 
something going on with my own system configuration somewhere.

I know the userdb query can set the nice value but mine (a mysql query) 
does not...

We're having problems with our mail partition being absolutely thrashed 
and thought over-strong imap processes might be a factor.

Many thanks,
Daniel