[mythtv-users] Raid Performance Tweaking

[Jens Axboe]

On Mon, Jul 10 2006, Blammo wrote:
> > One should note that when doing performance testing, you should try and
> > mimic the behaviour you are likely to see when the system has been put
> > into production. bonnie++ is fine for some things, however it doesn't
> > really mimic a myth-like setup.
> >
> > I wrote an io tester tool called fio for help with these sorts of
> > things. You can imitate a system with X threads reading at Y bandwidth
> > for instance, with a few writers tossed in (throttled or not), or
> > whatever you please. It should be quite doable to write a synthetic myth
> > like load with it. You can find the latest snapshot here:
> >
> > http://brick.kernel.dk/snaps/
> >
> > if you are interested, at the time of this email that would be
> > http://brick.kernel.dk/snaps/fio-git-20060616102504.tar.gz.
> 
> Thanks. That sounds like a great test. Is there a reference page
> somewhere for what you (and others) have seen for performance)?

Nothing specific to a myth setup, at least I don't know of any. It would
be interesting to set some testing up though, to compare.

> I forgot to mention IOZone as another interesting test to throw into the mix.

IOZone is a pretty good io testing tool, it's generates a lot of data
though. So it takes time to use it properly. For simple 'foo threads
doing the same thing' I find tiotest to be very useful as well. Mainly
because I'm lazy and it's to run-and-check.

-- 
Jens Axboe