Re: [Exim] Reducing mysql load

On Wed, Oct 29, 2003 at 10:14:42PM +0000, David Leggett said:
> I have my MTA (exim 4.24) set up here at home to take all its data from a
> mysql database. After looking at my mysql log I realised that exim was doing
> about 6-10 queries per incoming email.
> Most of those queries seem to me to be work that isnt needed.
> They are lookups to satisfy local_parts= and domains= for my routers, having 3
> different routers with exactly the same set of domains/local parts and
> exactlly the same query (SELECT local_part from mail_users WHERE
> local_part='$local_part' AND domain='$domain'; for local_part=)
> I am wondering if there is any way to reduce the load that this is putting on
> mysql, although I guess its not vital as I have very few users (and I dont
> ever anticipate having many).

You will probably buy some performance by turning on query caching. It's in the
mysql docs. It won't stop the queries but it will dramatically speed up
the case where the same queries are repeated.