WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

RE: [Xen-devel] Re: [Patch] the interface of invalidating qemu mapcache

To: "Keir Fraser" <Keir.Fraser@xxxxxxxxxxxx>, "Cui, Dexuan" <dexuan.cui@xxxxxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: RE: [Xen-devel] Re: [Patch] the interface of invalidating qemu mapcache
From: "Li, Xin B" <xin.b.li@xxxxxxxxx>
Date: Sat, 27 Jan 2007 03:33:03 +0800
Delivery-date: Fri, 26 Jan 2007 11:32:52 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
In-reply-to: <C1DFEE27.7E18%Keir.Fraser@xxxxxxxxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index: AcbhNpSgnLlsyleeR3aZurd/xO5mYAAmjw1QAHpYsZANUy+bAAbmp7kgAzBSt0AAA6R4dgADlbrA
Thread-topic: [Xen-devel] Re: [Patch] the interface of invalidating qemu mapcache
>
>The balloon driver is likely to free up pages scattered all over the
memory
>map. Since it does this in batches it will probably be easiest to
simply
>blow the entire mapcache at the end of a batch. This will make your
patch a
>lot smaller!
>

Yes, it's much simpler if we just blow the entire mapcache each time we
release memory to Xen or get some back from Xen.
-Xin 


>Making effective use of 1MB selective zapping will actually be hard for
the
>balloon driver -- either it will make a zap request for each page it
frees
>(which will be slow) or it will need to maintain a bitmap it fills in
during
>its batched work which it then scans-and-zaps at the end. It is
probably not
>worth the effort.
>

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel