From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [RFC PATCH 0/2] Expose available KVM free memory slot count to
 help avoid aborts
Date: Thu, 27 Jan 2011 11:28:47 +0200
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Cc: Alex Williamson <alex.williamson@redhat.com>,
	Jan Kiszka <jan.kiszka@web.de>,
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To: Avi Kivity <avi@redhat.com>
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On Thu, Jan 27, 2011 at 11:26:19AM +0200, Michael S. Tsirkin wrote:
> On Thu, Jan 27, 2011 at 11:21:47AM +0200, Avi Kivity wrote:
> > On 01/26/2011 02:08 PM, Michael S. Tsirkin wrote:
> > >>  >
> > >>  >I just mean that once you fault you map sptes and then you can use them
> > >>  >without exits.  mmio will cause exits each time. Right?
> > >>
> > >>  The swapper scanning sptes, ksmd, khugepaged, and swapping can all
> > >>  cause a page to be unmapped.  Though it should certainly happen with
> > >>  a much lower frequency than mmio.
> > >
> > >Right. That's why I say that sorting by size might not be optimal.
> > >Maybe a cache ...
> > 
> > Why would it not be optimal?
> > 
> > If you have 16GB RAM in two slots and a few megabytes here and there
> > scattered in some slots, you have three orders of magnitudes to
> > spare.
> 
> Yes but you might not be accessing all that RAM.
> Maybe your workset is just tens of megabytes.

Anyway, what I am saying this is all just guesswork.
Some kind of cache sounds, to me, like a better
approach if we have a ton of slots.


> > -- 
> > error compiling committee.c: too many arguments to function