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Date: Thu, 16 Jun 2011 15:49:40 +0300
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Subject: Re: [Qemu-devel] Image streaming and live block copy
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To: Kevin Wolf <kwolf@redhat.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>, Dor Laor <dlaor@redhat.com>, Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>, jes sorensen <jes.sorensen@redhat.com>, Marcelo Tosatti <mtosatti@redhat.com>, qemu-devel@nongnu.org, Adam Litke <agl@us.ibm.com>

On 06/16/2011 03:35 PM, Kevin Wolf wrote:
> * Image streaming is a normal image file plus copy-on-read plus a
> background task that copies data from the source image

Or a block-mirror started in degraded mode.

> * Live block copy is a block-mirror of two normal image files plus a
> background task that copies data from the source image

= block-mirror started in degraded mode

> The right solution is probably to implement COR and the background task
> in generic block layer code (no reason to restrict it to QED) and use it
> for both image streaming and live block copy. (This is a bit more
> complicated than it may sound here because guest writes must always take
> precedence over a copy - but doing complicated things is an even better
> reason to do it in a common place instead of duplicating)

Or in a block-mirror block format driver - generic code need not be 
involved.


-- 
error compiling committee.c: too many arguments to function