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Date: Wed, 8 Nov 2017 17:45:06 +0000
From: "Daniel P. Berrange" <berrange@redhat.com>
Message-ID: <20171108174506.GI12670@redhat.com>
Reply-To: "Daniel P. Berrange" <berrange@redhat.com>
References: <20171107104653.8913-1-paul.durrant@citrix.com>
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Subject: Re: [Qemu-devel] [PATCH v3] xen-disk: use an IOThread per instance
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To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: Paul Durrant <paul.durrant@citrix.com>, Kevin Wolf <kwolf@redhat.com>, Stefano Stabellini <sstabellini@kernel.org>, qemu-devel@nongnu.org, Max Reitz <mreitz@redhat.com>, Anthony Perard <anthony.perard@citrix.com>, xen-devel@lists.xenproject.org

On Wed, Nov 08, 2017 at 05:42:27PM +0000, Stefan Hajnoczi wrote:
> On Tue, Nov 07, 2017 at 05:46:53AM -0500, Paul Durrant wrote:
> > This patch allocates an IOThread object for each xen_disk instance and
> > sets the AIO context appropriately on connect. This allows processing
> > of I/O to proceed in parallel.
> > 
> > The patch also adds tracepoints into xen_disk to make it possible to
> > follow the state transtions of an instance in the log.
> 
> virtio-blk and virtio-scsi allow the user to specify an IOThread object.
> This allows users to configure the device<->IOThread mapping any way
> they like (e.g. 1:1, M:N).  Are you sure you want to hard-code the
> IOThread mapping?

I certainly think it'd be better for mgmt apps if all disks had the same
approach to IOThread mapping.

Regards,
Daniel
-- 
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