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] performance of pv drivers for windows

To: Sebastian Reitenbach <sebastia@xxxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-users] performance of pv drivers for windows
From: Alexander Piavlo <piavka@xxxxxxxxxxxx>
Date: Wed, 24 Sep 2008 10:53:53 +0300
Cc: xen-users@xxxxxxxxxxxxxxxxxxx
Delivery-date: Wed, 24 Sep 2008 00:54:56 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <200809240728.23080.sebastia@xxxxxxxxxxxxxxxxxxxx>
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: <200809221118.40873.sebastia@xxxxxxxxxxxxxxxxxxxx> <48D76C13.3060304@xxxxxxxxxxxx> <200809240728.23080.sebastia@xxxxxxxxxxxxxxxxxxxx>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Thunderbird (X11/20061206)
Sebastian Reitenbach wrote:
 1.5MB/s for random write access is not lousy , if you perform random
write test in dom0 or on native non xen kernel
you'll also get  1.5MB/s
Hm, ok, but without any PV drivers, I got about 7MB/sec. at least for writing to the disk.
This does not look realistic, especially since with random read you got only 1.6MB/sec. Maybe this is some QEMU caching issue. Also the graph shows 2 strange large time slots with zero write activity.

Would you mind running tiobench benchmark http://tiobench.sourceforge.net/ inside dom0 with:
         tiotest -t 4 -f 1024 -r 5000 -b 4096 -d /test
where /test is a mountpoint of a newly created ext3 filesystem large enough to hold 1024*4 MB
or better yet:
        tiotest -t THREADS -f SIZE -r 5000 -b 4096 -d /test
where THREADS*SIZE > 2*(Available RAM)


Therefore I was wondering.

Xen-users mailing list