From mboxrd@z Thu Jan  1 00:00:00 1970
From: Anthony Liguori <aliguori@us.ibm.com>
Subject: Re: Are there plans to achieve ram live Snapshot feature?
Date: Fri, 09 Aug 2013 10:45:22 -0500
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To: Chijianchun <chijianchun@huawei.com>,
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Chijianchun <chijianchun@huawei.com> writes:

> Now in KVM, when RAM snapshot, vcpus needs stopped, it is Unfriendly restrictions to users.
>
> Are there plans to achieve ram live Snapshot feature?

I think you mean a live version of the savevm command.

You can approximate live migrating to a file, creating an external disk
snapshot, then resuming the guest.

Regards,

Anthony Liguori

>
> in my mind, Snapshots can not occupy additional too much memory, So when the memory needs to be changed, the old memory page is needed to flush to the file first.  But flushing to file is too slower than memory,  and when flushing, the vcpu or VM is need to be paused until finished flushing,  so pause...resume...pause...resume............., more and more slower.
>
> Is this idea feasible? Are there any other thoughts?