Date:   Tue, 30 Nov 2021 11:05:13 -0500
From:   Bruce Fields <bfields@fieldses.org>
To:     Chuck Lever III <chuck.lever@oracle.com>
Cc:     Dai Ngo <dai.ngo@oracle.com>,
        Trond Myklebust <trondmy@hammerspace.com>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        "linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>
Subject: Re: [PATCH RFC v5 0/2] nfsd: Initial implementation of NFSv4
 Courteous Server
Message-ID: <20211130160513.GC8837@fieldses.org>
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On Tue, Nov 30, 2021 at 03:36:43PM +0000, Chuck Lever III wrote:
> I am a little concerned that we are trying to optimize a case
> that won't happen during practice. pynfs does not reflect any
> kind of realistic or reasonable client behavior -- it's designed
> to test very specific server operations.

I wonder how hard this problem would be to hit in normal use.  I mean, a
few hundred or a thousand clients doesn't sound that crazy.  This case
depends on an open deny, but you could hit the same problem with file
locks.  Would it be that weird to have a client trying to get a write
lock on a file read-locked by a bunch of other clients?

--b.