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/
Home Products Support Community News


Re: [Xen-users] IO caching at dom0 level

To: xen-users@xxxxxxxxxxxxxxxxxxx
Subject: Re: [Xen-users] IO caching at dom0 level
From: "Olivier B." <xen.list@xxxxxxxxx>
Date: Mon, 07 Sep 2009 22:35:44 +0200
Delivery-date: Mon, 07 Sep 2009 13:36:28 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <7207d96f0909071319j7e764ecfxb2e4c6d64727201c@xxxxxxxxxxxxxx>
List-help: <mailto:xen-users-request@lists.xensource.com?subject=help>
List-id: Xen user discussion <xen-users.lists.xensource.com>
List-post: <mailto:xen-users@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=unsubscribe>
References: <4AA5312E.7070506@xxxxxxxxx> <7207d96f0909071319j7e764ecfxb2e4c6d64727201c@xxxxxxxxxxxxxx>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Mozilla-Thunderbird (X11/20090707)
Fajar A. Nugraha wrote:
On Mon, Sep 7, 2009 at 11:13 PM, Olivier B.<xen.list@xxxxxxxxx> wrote:

is there a way to maintain an IO cache on dom0 for all domU ?

Generally not recommended as it could cause data corruption on domU side.
If you REALLY want to use it anyway despite the consequences, AFAIK
file:/ does that by default, and it should work even for block
Well if you only do read caching, what problem can you have ?
And for write caching, the problem is the same as for write cache on RAID cards, so barriers should already avoid problems with that, no ?

I will look at your suggestion, thanks.

I have near 1Go not used ram on a Dom0, and would like to use this memory to
speedup all the domU. All my domU use LVM phy devices.

1G is not much :P. IMHO you better add it to the busiest domU.
Well to simulate a "raid hard card", it's enough I think ;)


Xen-users mailing list

<Prev in Thread] Current Thread [Next in Thread>