Re: skip file setup?

On Mon, Nov 26 2007, Shawn Lewis wrote:
> Nevermind, looks like write phases don't actually extend the file, which is
> what I'm looking for. :) Maybe there was an older version of fio that didn't
> do this, or I'm just crazy.

Only option in that area is 'overwrite', which controls whether the
write phase is an overwrite or new write. The file setup will still
ftruncate() and posix_fallocate() the blocks. How about an option for
skipping the fallocate? It'll definitely result in a zero fill for lots
of systems.

>
> Thanks!
> Shawn
>
> On Nov 26, 2007 8:14 PM, Shawn Lewis <shawnlewis_at_google.com> wrote:
>
> > Jens,
> >
> > Does any combination of fio options allow us to completely skip file
> > setup? I'd like to have a thread with rw=write size=300g that doesn't ever
> > do file setup. This is useful if you want to have a write phase and then a
> > verify phase and you don't care about performance. If this doesn't exist
> > I'll send a patch.
> >
> > It's also useful because runtime can't cap the time for the file setup
> > phase, so if you have a really slow disk it'll take forever to lay the file
> > out.
> >
> > Thanks,
> > Shawn
> >

-- 
Jens Axboe