LARGE single-system Cyrus installs?

[Michael D. Sofka]

On Thursday 08 November 2007 10:56:54 am Dan White wrote:
> Michael D. Sofka wrote:
> > On Thursday 04 October 2007 07:32:52 pm Rob Mueller wrote:
> >> 4. Lots of other little things
> >>
> >> a) putting the proc dir on tmpfs is a good idea
> >> b) make sure you have the right filesystem (on linux, reiserfs is much
> >> better than ext3 even with ext3s dir hashing) and journaling modes
> >
> > On a Murder front-end server, could the tls_sessions.db be put on a
> > tmpfs?  What about mailboxes.db, since the murder master would have
> > the master copy anyway.  (This would slowdown startup in the case
> > of the system loosing power.  But, ``the front end servers can be
> > considered 'dataless' '' according to:
> > http://cyrusimap.web.cmu.edu/ag.html)
> >
> > We have a Murder Aggregate with two front-end and three back-end
> > servers, and the master.   I've noticed the front-end servers are a
> > little IO bound.  They each have a single disk, and I discovered that
> > half of the IO wait went away when I buffered the cyrus.log file in
> > syslogd. But, they still show an average of 5-6% IO Wait for processes.
> >
> > Moving imap/proc to tmpfs, however, had a negligible effect.
> >
> >  I'll spec a two-disk system when new front-end's are ordered,
> > but that would only split system from cyrus.   Would it make more
> > sense (and, more importantly, would it work and not foobar us) to order
> > a machine with more memory, and put configdirectory: on tmpfs?  (With
> > the possible exception of the db snapshots and mboxlist backups.)
> >
> > Mike
>
> Hi Mike,
>
> While reviewing this thread for optimization ideas, I came across
> your comment about buffering the cyrus.log in syslogd. Could you
> explain what you did to configure that?
>
> Thanks,
> - Dan White
> BTC Broadband

Put a '-' in front of a of the file name.  E.g.:

local6.*                                    -/var/log/cyrus.log


Mike

-- 
Michael D. Sofka               sofkam at rpi.edu
C&MT Sr. Systems Programmer,   Email, TeX, Epistemology
Rensselaer Polytechnic Institute, Troy, NY.  http://www.rpi.edu/~sofkam/