From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Mike D. Day" <ncmike@us.ibm.com>
Subject: Re: Page sharing in Xen?
Date: Wed, 12 Jul 2006 10:20:55 -0400
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To: Keir Fraser <Keir.Fraser@cl.cam.ac.uk>
Cc: Jae-Wan Jang <jwjang@camars.kaist.ac.kr>, xen-devel@lists.xensource.com
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Keir Fraser wrote:
> 
> On 12 Jul 2006, at 03:38, Jae-Wan Jang wrote:
> 
>> I want to know whether Xen shares pages between domains or not.
>> When I read "Memory Resource Management in VMware ESX server",
>> they use page sharing between domains with hash value of a page.
>> So I wonder that Xen uses this technique
>> or if not, is there anyone who is implementing this to Xen now or
>> willing to do so.
> 
> There is explicit page sharing in Xen, but the kind of automatic scheme 
> described in that paper. This is largely because it's unclear how great 
> the benefit would be in practice.

Page coalescing is a frequently requested feature, not just for Xen/x86 
but for other platforms/Hypervisors. It would be good if we can 
incorporate it into Xen.

Mike