Re: [libvirt] Horrible performance of virDomainGetInfo()
On Wed, Dec 07, 2011 at 03:45:10PM +0100, Jiri Denemark wrote:
On Wed, Dec 07, 2011 at 14:30:10 +0000, Daniel P. Berrange wrote:
> While investigating the RPC problems I've noticed that we have had a
> huge performance regression for virDomainGetInfo() due to the change
> which makes virDomainEndJob() save the XML status file every time it
> is called.
>
> Previous to this change, 2000 calls to virDomainGetInfo() took ~2.5 seconds
>
> After this change, 2000 calls to virDomainGetInfo() take 2 *minutes* 45 secs
>
> I don't have an answer right now and it shouldnt block the release, but we
> have todo something to avoid this overhead.
I think we could change job APIs to only save XML status if async job is
active since we are currently not really interested in other jobs anyway.
Ok, that sounds like a reasonable idea. Could you cook up a patch for
that.
Daniel
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