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Date: Tue, 04 Mar 2014 19:28:10 +0800
From: Wenchao Xia <wenchaoqemu@gmail.com>
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Subject: Re: [Qemu-devel] [RFC]VM live snapshot proposal
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: "kwolf@redhat.com" <kwolf@redhat.com>, Pavel Hrdina <phrdina@redhat.com>, Zhanghailiang <zhang.zhanghailiang@huawei.com>, KVM devel mailing list <kvm@vger.kernel.org>, Stefan Hajnoczi <stefanha@gmail.com>, "Huangpeng (Peter)" <peter.huangpeng@huawei.com>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, Wenchao Xia <xiawenc@linux.vnet.ibm.com>

于 2014/3/4 17:05, Paolo Bonzini 写道:
> Il 04/03/2014 09:54, Stefan Hajnoczi ha scritto:
>>> Is there any other proposals to implement vm-snapshot?
>> See the discussion by Paolo and Andrea about post-copy migration, which
>> adds kernel memory management features for tracking userspace page
>> faults. Perhaps you can use that infrastructure to trap guest writes.
>
> That infrastructure actually traps guest reads too. But it's fine, as 
> they are a superset of guest writes and the image will still be 
> consistent.
>
> Paolo
>
I heard that Kernel going to have API to let userspace catch memory 
operation, which originally
can be only caught by kernel code. I am not sure how it is now, but if 
kernel have it, qemu
can use it more gracefully than modifing migration code.