From: Paolo Bonzini <pbonzini@redhat.com>
To: Zhang Haoyu <zhanghy@sangfor.com.cn>, qemu-devel <qemu-devel@nongnu.org>
Cc: Gleb Natapov <gleb@kernel.org>, Kevin Wolf <kwolf@redhat.com>,
Peter Lieven <pl@kamp.de>, Stefan Hajnoczi <stefanha@redhat.com>
Subject: Re: [Qemu-devel] question about live migration with storage
Date: Wed, 25 Mar 2015 14:07:50 +0100 [thread overview]
Message-ID: <5512B326.9030007@redhat.com> (raw)
In-Reply-To: <201503101001341072349@sangfor.com.cn>
On 10/03/2015 03:01, Zhang Haoyu wrote:
> My test results show that when using thin-provisioning qcow2
> image(created by qemu-img create -f qcow2 preallocation=metadata),
> even the unallocated sectors will be transferred to destination, so
> much data is transferred, so the qcow2 image in destination is full
> allocated.
Yes, metadata preallocation actually allocates all sectors. Only, the
qcow2 image is sparse so the sectors do not consume space on the source.
I think you can avoid the problem by passing file.detect-zeroes=unmap in
the -drive option of the destination QEMU. Kevin/Peter, can you confirm
this should work?
Paolo
prev parent reply other threads:[~2015-03-25 13:08 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-01-13 1:48 [Qemu-devel] question about live migration with storage Zhang Haoyu
2015-01-13 2:03 ` Zhang Haoyu
2015-01-13 9:45 ` Paolo Bonzini
2015-01-14 2:41 ` Zhang Haoyu
2015-01-14 7:34 ` Paolo Bonzini
2015-01-14 7:58 ` Zhang Haoyu
2015-01-14 9:06 ` Paolo Bonzini
2015-01-15 3:54 ` Zhang Haoyu
2015-01-15 9:11 ` Paolo Bonzini
2015-01-15 9:56 ` Zhang Haoyu
2015-01-15 10:08 ` Paolo Bonzini
2015-03-10 2:01 ` Zhang Haoyu
2015-03-25 13:07 ` Paolo Bonzini [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=5512B326.9030007@redhat.com \
--to=pbonzini@redhat.com \
--cc=gleb@kernel.org \
--cc=kwolf@redhat.com \
--cc=pl@kamp.de \
--cc=qemu-devel@nongnu.org \
--cc=stefanha@redhat.com \
--cc=zhanghy@sangfor.com.cn \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.