Re: [PATCH 2/2] generic/530: only use xfs-specific mkfs options when testing on xfs

[Christoph Hellwig <hch@infradead.org>]

On Thu, Dec 19, 2024 at 09:26:06AM +1100, Dave Chinner wrote:
> On Tue, Dec 17, 2024 at 12:11:07AM -0800, Christoph Hellwig wrote:
> > On Sun, Dec 15, 2024 at 12:12:42AM -0500, Theodore Ts'o wrote:
> > > +if [ $FSTYP = "xfs" ]; then
> > > +    _scratch_mkfs "-l size=256m" >> $seqres.full 2>&1
> > > +else
> > > +    _scratch_mkfs >> $seqres.full 2>&1
> > > +fi
> > 
> > We really need to document why generic tests have file system specific
> > hacks.  And yes, that's a request for Dave who originally added it
> > without any explanation and not Ted.
> 
> Creating and then unlinking 50000 files is journal space bound
> when using default 64MB logs on small test filesystems. Increasing
> the journal size to 256MB halved the runtime of this test.

Please explain this in thet test.  And you probably also want to
ensure that you don't force the log smaller than 256 either, otherwise
people in 10 or 20 years will wonder why this test forces logs to
be so small.