Re: [PATCH 0/4] ksm - dynamic page sharing driver for linux

Andrew Morton
2008-11-11T19:22:20Z

On Tue, 11 Nov 2008 21:07:10 +0200
Izik Eidus <ieidus@redhat.com> wrote:

> we have used KSM in production for about half year and the numbers that
> came from our QA is:
> using KSM for desktop (KSM was tested just for windows desktop workload)
> you can run as many as
> 52 windows xp with 1 giga ram each on server with just 16giga ram. (this
> is more than 300% overcommit)
> the reason is that most of the kernel/dlls of this guests is shared and
> in addition we are sharing the windows zero
> (windows keep making all its free memory as zero, so every time windows
> release memory we take the page back to the host)
> there is slide that give this numbers you can find at:
> http://kvm.qumranet.com/kvmwiki/KvmForum2008?action=AttachFile&do=get&target=kdf2008_3.pdf
> (slide 27)
> beside more i gave presentation about ksm that can be found at:
> http://kvm.qumranet.com/kvmwiki/KvmForum2008?action=AttachFile&do=get&target=kdf2008_12.pdf

OK, 300% isn't chicken feed.

It is quite important that information such as this be prepared, added to
the patch changelogs and maintained. For a start, without this basic
information, there is no reason for anyone to look at any of the code!