From: Alex Bligh <alex@alex.org.uk>
To: "Myklebust, Trond" <Trond.Myklebust@netapp.com>
Cc: linux-nfs@vger.kernel.org, ian.campbell@citrix.com,
Alex Bligh <alex@alex.org.uk>
Subject: Re: Fatal crash with NFS, AIO & tcp retransmit
Date: Wed, 23 Jan 2013 17:33:53 +0000 [thread overview]
Message-ID: <5B18F9B0446E7F3CAA3BD81D@nimrod.local> (raw)
In-Reply-To: <4FA345DA4F4AE44899BD2B03EEEC2FA91832D572@sacexcmbx05-prd.hq.netapp.com>
--On 23 January 2013 15:34:42 +0000 "Myklebust, Trond"
<Trond.Myklebust@netapp.com> wrote:
> I've no idea if they do zero copy to the socket in these situations. If
> they do, then they probably have similar issues. The problem can be
> mitigated by breaking the connection on retransmission; we can't do that
> in NFS < NFSv4.1, since the duplicate replay cache is typically indexed
> to the port number (and port number reuse is difficult with TCP due to
> the existence of the TIME_WAIT state).
If you break the connection, and the written data is now not available
to dom0 (as it's been mapped out), how would it ever get resent? IE
it's not going to be available to the RPC layer either.
--
Alex Bligh
next prev parent reply other threads:[~2013-01-23 17:34 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-01-21 13:06 Fatal crash with NFS, AIO & tcp retransmit Alex Bligh
2013-01-21 14:38 ` Myklebust, Trond
2013-01-21 15:01 ` Alex Bligh
2013-01-21 15:10 ` Alex Bligh
2013-01-21 15:21 ` Ian Campbell
2013-01-25 13:45 ` Alex Bligh
2013-01-21 15:50 ` Myklebust, Trond
2013-01-21 15:54 ` Ian Campbell
2013-01-21 17:12 ` Alex Bligh
2013-01-21 17:20 ` Myklebust, Trond
2013-01-21 17:29 ` Alex Bligh
2013-01-23 15:22 ` Alex Bligh
2013-01-23 15:34 ` Myklebust, Trond
2013-01-23 17:33 ` Alex Bligh [this message]
2013-01-23 17:37 ` Myklebust, Trond
2013-01-23 17:42 ` Alex Bligh
2013-01-23 17:48 ` Peter Staubach
2013-01-23 18:13 ` Myklebust, Trond
2013-01-23 19:37 ` Alex Bligh
2013-01-24 10:42 ` Ian Campbell
2013-01-24 12:00 ` Alex Bligh
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