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Date: Mon, 14 Mar 2011 10:13:22 -0500
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: [Qemu-devel] Re: Strategic decision: COW format
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To: Kevin Wolf <kwolf@redhat.com>
Cc: Chunqiang Tang <ctang@us.ibm.com>, Stefan Hajnoczi <stefanha@gmail.com>, Markus Armbruster <armbru@redhat.com>, Aurelien Jarno <aurelien@aurel32.net>, qemu-devel@nongnu.org

On 03/14/2011 10:03 AM, Kevin Wolf wrote:
>>> The only problem with them is that they are metadata that must be
>>> updated. However, I think we have discussed enough how to avoid the
>>> greatest part of that cost.
>> Maybe I missed it, but in the WCE=0 mode, is it really possible to avoid
>> the writes for the refcount table?
> Protected by a dirty flag (and/or a journal), sure. I mean, wasn't that
> the whole point of starting the qcow3 discussion?

Okay, I thought you had something else in mind.

Regards,

Anthony Liguori

> Kevin
>