From: Eric Blake <eblake@redhat.com>
To: Thomas Knauth <thomas.knauth@gmx.de>
Cc: Stefan Hajnoczi <stefanha@gmail.com>, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] kvm suspend performance
Date: Mon, 25 Mar 2013 09:05:31 -0600 [thread overview]
Message-ID: <515067BB.5060600@redhat.com> (raw)
In-Reply-To: <CABhLV00LaBOjuMEhwUH41Z4cs8Mbfn4MMLBu+r8jKQ69SZRS_A@mail.gmail.com>
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On 03/23/2013 06:42 AM, Thomas Knauth wrote:
> Hi Eric,
>
> thanks for the reply. This indeed solved my issue. Suspending is much
> faster without the artificial throttle.
>
> On a related note: I'm curious about the baseline resume latency. It takes
> about 5 seconds to resume an instance with a tiny amount of state (500 MB
> dump size). The data is all in the page cache. I measure the time it takes
> the 'virsh restore <dump file>' command to return.
>
> Any opinions on what could be the issue here? I've also linked to a figure
> illustrating the problem. Resume speed scales nicely with increased dump
> size, but the baseline penalty feels awfully high
Sorry, but I haven't ever profiled it to see where the problems might
lie. It sounds like it might be an interesting project if you want to
take it on, but I don't have the time to spend on it myself at the moment.
--
Eric Blake eblake redhat com +1-919-301-3266
Libvirt virtualization library http://libvirt.org
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prev parent reply other threads:[~2013-03-25 15:05 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-03-19 16:24 [Qemu-devel] kvm suspend performance Thomas Knauth
2013-03-20 8:11 ` Stefan Hajnoczi
2013-03-20 22:44 ` Thomas Knauth
2013-03-20 23:06 ` Eric Blake
2013-03-23 12:42 ` Thomas Knauth
2013-03-25 15:05 ` Eric Blake [this message]
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