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From:   "NeilBrown" <neilb@suse.de>
To:     "Daire Byrne" <daire@dneg.com>
Cc:     "J. Bruce Fields" <bfields@fieldses.org>,
        "Patrick Goetz" <pgoetz@math.utexas.edu>,
        "linux-nfs" <linux-nfs@vger.kernel.org>
Subject: Re: parallel file create rates (+high latency)
In-reply-to: <CAPt2mGOx0qNTWoY9vmyVBtZ3gxdbv5qQ-2qVbtqWW9FiZFRhEg@mail.gmail.com>
References: <CAPt2mGOaRsKOiL_wuSK_D5oYYnn0R-pvVsZc5HYGdEbT2FngtQ@mail.gmail.com>,
 <20220124193759.GA4975@fieldses.org>,
 <adce2b72-ed5c-3056-313c-caea9bad4e15@math.utexas.edu>,
 <20220125212055.GB17638@fieldses.org>,
 <164315533676.5493.13243313269022942124@noble.neil.brown.name>,
 <20220126025722.GD17638@fieldses.org>,
 <CAPt2mGP2guMMf1C9VoQ0AvZ819jPuz0vDoEzJJhtL8q5DJ300A@mail.gmail.com>,
 <CAPt2mGNXq==1KUskF3U6-CDeoX57=d7NW4Qn_esDqarf9bTBaw@mail.gmail.com>,
 <20220211155949.GA4941@fieldses.org>,
 <CAPt2mGOx0qNTWoY9vmyVBtZ3gxdbv5qQ-2qVbtqWW9FiZFRhEg@mail.gmail.com>
Date:   Fri, 18 Feb 2022 18:46:49 +1100
Message-id: <164517040900.10228.8956772146017892417@noble.neil.brown.name>
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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!

Thanks,
NeilBrown