public inbox for linux-nfs@vger.kernel.org
 help / color / mirror / Atom feed
From: bfields@fieldses.org (J. Bruce Fields)
To: Frank van der Linden <fllinden@amazon.com>
Cc: Wang Yugui <wangyugui@e16-tech.com>, linux-nfs@vger.kernel.org
Subject: Re: nfsd dead loop when xfstests generic/531
Date: Tue, 8 Jun 2021 13:20:15 -0400	[thread overview]
Message-ID: <20210608172015.GB22685@fieldses.org> (raw)
In-Reply-To: <20210601165535.GA3102@dev-dsk-fllinden-2c-d7720709.us-west-2.amazon.com>

On Tue, Jun 01, 2021 at 04:55:35PM +0000, Frank van der Linden wrote:
> On Mon, May 31, 2021 at 12:59:51PM +0800, Wang Yugui wrote:
> > 
> > 
> > Hi,
> > 
> > nfsd dead loop when xfstests generic/531
> > 
> > linux kernel of nfs server: 5.10.41
> > linux kernel of nfs client: 5.10.41
> > 
> > 
> > nfsd dead loop when xfstests generic/531
> > 
> > linux kernel of nfs server: 5.10.41
> > linux kernel of nfs client: 5.10.41
> 
> This is a known issue. generic/531 opens a large number of files, causing
> the nfsd file cache code to walk a very long LRU list of open files. For
> v4, there will be a lot of long term opens (because of the OPEN call),
> and they all end up on that list.
> 
> So, the basic issue is, that the nfsd file cache is a good match for
> v3 semantics, but less so for v4 semantics.
> 
> I posted an experimental patch to work around the issue:
> 
> https://lore.kernel.org/linux-nfs/20201020183718.14618-4-trondmy@kernel.org/T/#m869aa427f125afee2af9a89d569c6b98e12e516f
> 
> The rhashtable patch has issues, so disregard that one, but the other one
> is a basic fix for this issue. It has one other issue that I noticed (refcount
> error), but that is easily fixed.
> 
> I should update the patch and formally post it..

That would be great.

--b.

      reply	other threads:[~2021-06-08 17:20 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-31  4:59 nfsd dead loop when xfstests generic/531 Wang Yugui
2021-06-01  2:54 ` Wang Yugui
2021-06-01 16:55 ` Frank van der Linden
2021-06-08 17:20   ` J. Bruce Fields [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210608172015.GB22685@fieldses.org \
    --to=bfields@fieldses.org \
    --cc=fllinden@amazon.com \
    --cc=linux-nfs@vger.kernel.org \
    --cc=wangyugui@e16-tech.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox