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Date: Thu, 15 Sep 2016 05:41:03 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Alex Bligh <alex@alex.org.uk>
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Subject: Re: [Nbd] [RESEND][PATCH 0/5] nbd improvements
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On Thu, Sep 15, 2016 at 01:39:11PM +0100, Alex Bligh wrote:
> That's probably right in the case of file-based back ends that
> are running on a Linux OS. But gonbdserver for instance supports
> (e.g.) Ceph based backends, where each connection might be talking
> to a completely separate ceph node, and there may be no cache
> consistency between connections.

Yes, if you don't have a cache coherent backend you are generally
screwed with a multiqueue protocol.