Subject: Re: remplacing page mappings behind uvm
To: YAMAMOTO Takashi <>
From: Manuel Bouyer <>
List: tech-kern
Date: 12/01/2007 16:43:42
On Sat, Dec 01, 2007 at 01:28:35PM +0100, Manuel Bouyer wrote:
> On Sat, Dec 01, 2007 at 07:04:59PM +0900, YAMAMOTO Takashi wrote:
> > > I played with this, it seems to work. See the attached privcmd.c
> > > There is a wired entry accounting issue I still need to solve,
> > > which I think is related to MMAPBATCH, but it looks promising.
> > 
> > i wonder how many objects are used with the usage pattern of xentools.
> I'd say a few 10s for qemu-dm. But it's dynamic, they are mmaped and then
> unmapped. I'll add a counter to watch it.

It needs about 4500 to start a PV guest, but it's only to load the
kernel. Once the guest is started it's keept at 2.
It needs 13 to run a winXP HVM guest

Manuel Bouyer <>
     NetBSD: 26 ans d'experience feront toujours la difference