From: Andrew W Elble <aweits@rit.edu>
To: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Olga Kornievskaia <aglo@umich.edu>, linux-nfs <linux-nfs@vger.kernel.org>
Subject: Re: [PATCH 1/1] Adding issync field to delegreturn_exit tracepoint
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Date: Tue, 13 Oct 2015 13:58:29 -0400
In-Reply-To: <CAHQdGtQJm6rFiNgF+SVCx_3SAnzBgHu8mXToWu_uNwJHYCZzqA@mail.gmail.com>
	(Trond Myklebust's message of "Tue, 13 Oct 2015 13:28:08 -0400")
Message-ID: <m2fv1esla2.fsf@discipline.rit.edu>
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Trond Myklebust <trond.myklebust@primarydata.com> writes:

>> > OK. So what are the symptoms? I'm having trouble seeing how a race can
>> > happen, given a correctly coded server.
>>
>> Here's what the server sees:
>> open (foobar) replies back with a delegation
>> various operations including a close()
>> some time goes by...
>> open (foobar) replies back with the same delegation
>
> Why? Olga, we already had this discussion. That sort of server
> behaviour is never going to work without races and is the root cause
> of your problem. We simply won't ever support servers that do this.

Trond,

  Specifically, what would the correct behavior be here?

Thanks,

Andy

-- 
Andrew W. Elble
aweits@discipline.rit.edu
Infrastructure Engineer, Communications Technical Lead
Rochester Institute of Technology
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