Re: [PATCH 4/4] xfstests: Speed up test 042

Alex Elder
2011-02-02T01:27:41Z

On Tue, 2011-01-25 at 14:58 +1100, Dave Chinner wrote:
> From: Dave Chinner <dchinner@redhat.com>
>
> test 042 generates a worst-case fragmented filesystem and uses it to
> test xfs_fsr. It uses small 4k files to generate the hole-space-hole
> pattern that fragments free space badly. It is much faster to
> generate the same pattern by creating a single large file and
> punching holes in it. Also, instead of writing large files to
> create unfragmented space, just use preallocation so we don't have
> to write the data to disk.
>
> These changes reduce the runtime of the test on a single SATA drive
> from 106s to 27s.
>
> Signed-off-by: Dave Chinner <dchinner@redhat.com>

Perhaps your test system is configured different
from mine, but I don't see the speedup you see.
In fact, it might have slowed it down. I really
haven't experimented much though and will report
back if I find anything more constructive to say.

Other than that I see no problem with the change.
And the difference either way isn't a big deal
to me, so:

Reviewed-by: Alex Elder <aelder@sgi.com>