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From:   Daire Byrne <daire@dneg.com>
Date:   Mon, 21 Feb 2022 13:59:16 +0000
Message-ID: <CAPt2mGMLQCEPqsYGeaMd3BPGRne4F4h-2-pzqm1a8nwfKqv1ug@mail.gmail.com>
Subject: Re: parallel file create rates (+high latency)
To:     NeilBrown <neilb@suse.de>
Cc:     "J. Bruce Fields" <bfields@fieldses.org>,
        Patrick Goetz <pgoetz@math.utexas.edu>,
        linux-nfs <linux-nfs@vger.kernel.org>
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On Fri, 18 Feb 2022 at 07:46, NeilBrown <neilb@suse.de> wrote:
>
> On Fri, 18 Feb 2022, Daire Byrne wrote:
> > On Fri, 11 Feb 2022 at 15:59, J. Bruce Fields <bfields@fieldses.org> wrote:
> >
> > > I think the path forward would be to update Neil's patch, add your
> > > performance data, send it to Al and linux-fsdevel, and see if we can get
> > > some idea what remains to be done to get this right.
> >
> > If Neil or anyone else is able to do that work, I'm happy to test and
> > provide the numbers.
> >
> > If I could update the patch myself, I would have happily contributed
> > but I lack the experience or knowledge. I'm great at identifying
> > problems, but not so hot at solving them :)
> >
>
> I've ported it to mainline without much trouble.  I started some simple
> testing (parallel create/delete of the same file) and hit a bug quite
> easily.  I fixed that (eventually) and then tried with more than 1 CPU,
> and hit another bug.  But then it was quitting time.  If I can get rid
> of all the easy to find bugs, I'll post it with a CC to you, and you can
> find some more for me!

That would be awesome! I have a real world production case for this
and it's a pretty heavy workload. If that doesn't shake out any bugs,
nothing will.

The only caveat being that it will likely be restricted to NFSv3
testing due to the concurrency limitations with NFSv4.1+ (from the
other thread).

Daire