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Date: Mon, 03 Mar 2014 14:19:37 +0100
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [RFC]VM live snapshot proposal
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To: Kevin Wolf <kwolf@redhat.com>, Stefan Hajnoczi <stefanha@gmail.com>
Cc: Pavel Hrdina <phrdina@redhat.com>, Zhanghailiang <zhang.zhanghailiang@huawei.com>, KVM devel mailing list <kvm@vger.kernel.org>, "Huangpeng (Peter)" <peter.huangpeng@huawei.com>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, Wenchao Xia <xiawenc@linux.vnet.ibm.com>

Il 03/03/2014 13:55, Kevin Wolf ha scritto:
>>> > > Due to memory-modifications may happen in kvm, qemu, or vhost, the key-part is how we
>>> > > can provide common page-modify-tracking-and-saving api, we completed a prototype by
>>> > > simply add modified-page tracking/saving function in qemu, and it seems worked fine.
>> >
>> > Yes, this is the tricky part.  To be honest, I think this is the reason
>> > no one has submitted patches - it's a hard task and the win isn't that
>> > great (you can already migrate to file).
> So why don't we simply reuse the existing migration code?

I think this is different in the same way that block-backup and 
block-mirror are different.  Huangpeng's proposal would let you make a 
consistent snapshot of disks and RAM.

Paolo