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From: 858585 jemmy <jemmy858585@gmail.com>
Date: Mon, 24 Apr 2017 20:26:06 +0800
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Subject: Re: [Qemu-devel] [PATCH v6] migration/block: use blk_pwrite_zeroes
 for each zero cluster
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To: Fam Zheng <famz@redhat.com>
Cc: qemu block <qemu-block@nongnu.org>, Juan Quintela <quintela@redhat.com>, qemu-devel <qemu-devel@nongnu.org>, Dave Gilbert <dgilbert@redhat.com>, Stefan Hajnoczi <stefanha@redhat.com>, Lidong Chen <lidongchen@tencent.com>

On Mon, Apr 24, 2017 at 8:19 PM, Fam Zheng <famz@redhat.com> wrote:
> On Mon, 04/24 20:09, Fam Zheng wrote:
>> It's a separate problem.
>
> To be specific:
>
> 1) there is an option "overlap-check" that one can use to
> disable the costly metadata check;
yes, i will disable metadata check, and test the performance again.

>
> 2) qcow2 with cluster_size = 512 is probably too uncommon to be optimized for.
if culster_size is very small, should disable metadata check default?

>
> Both are irrelevant to why and how this patch can be improved, IMO.
>
> Fam