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-users

Re: [Xen-users] Xen hard-disk performance regression?

To: xen-users@xxxxxxxxxxxxxxxxxxx
Subject: Re: [Xen-users] Xen hard-disk performance regression?
From: Fabiano Francesconi <fabiano.francesconi@xxxxxxxxx>
Date: Sun, 11 Apr 2010 17:39:27 +0200
Delivery-date: Sun, 11 Apr 2010 08:40:48 -0700
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:date:from:to:subject :message-id:mail-followup-to:references:mime-version:content-type :content-disposition:in-reply-to:user-agent; bh=HZdKjCFmKVgmOoH8caAb1E3NT5i6rjdbGiZozLqXupk=; b=HI9tkP9YtycoLgWtW072OFi51Owo3kjE018exmmKt/zptybNFtSEsTbACdXe/PLZ8k End6SEJWItuw2bYPEEyFsaex61n69zgoLd8satcPjGjZ8c984zr4w2OYvY1AmAVnOZ5V FxGU9BCKTvAXJPWIAss9Wig5QnwEgfyGTmpOE=
Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:subject:message-id:mail-followup-to:references :mime-version:content-type:content-disposition:in-reply-to :user-agent; b=vaZmyxE7z4kMcoisQG9DGPH7KkeuKnEQOpUVhD2a+khzFOzNXjIOb3OyZkwuHK6HeV YE0cx63KGcCFXXyC7ykCAB7y3iMnNk9ZytsU5PkRpjifHySltNuam7a0ndzaTFU7msUN 6rhaS7yBv87bFuRAbNnbedCABil9Rgp0M+GEc=
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <h2jf4527be1004110655g4d61faa9va243867256de8a0f@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>
Mail-followup-to: xen-users@xxxxxxxxxxxxxxxxxxx
References: <20100411103057.GA3244@whitebox> <h2jf4527be1004110655g4d61faa9va243867256de8a0f@xxxxxxxxxxxxxx>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Mutt/1.5.20 (2009-06-14)
On Sun, Apr 11, 2010 at 02:55:24PM +0100, Andrew Lyon wrote:
> On Sun, Apr 11, 2010 at 11:30 AM, Fabiano Francesconi
> <fabiano.francesconi@xxxxxxxxx> wrote:
> > Hello there,
> > I'm noticing a performance regression for what's matter the hard-disk I
> > pass to the domU (aquaria).
> 
> 
> Have you checked the performance of the disk in dom0?
> 
> >
> > The slow-down is very noticeable even when moving small videos file
> > (~350mb).
> >
> > In the configuration file of the domU, I pass the whole disk
> > ('phy:/dev/sdb,xvdb,w') to the guest OS.
> >
> > The distribution under both systems is Gentoo/Linux, x86 arch.
> >
> > The hypervisor is always the same, in both scenarios (Linux xevelon
> > 2.6.32-xen-r1 #1 SMP Sat Apr 10 13:37:02 CEST 2010 i686 Intel(R)
> > Atom(TM) CPU 330 @ 1.60GHz GenuineIntel GNU/Linux).
> >
> > The machine is an Atom, so it's not capable of any VT technology but so
> > far it's a great machine and XEN is working just fine on it.
> >
> > I attach you few logs I've gathered.
> >
> > Thank you
> >
> > --
> > Fabiano Francesconi [GPG key: 0x81E53461]
> >
> > _______________________________________________
> > Xen-users mailing list
> > Xen-users@xxxxxxxxxxxxxxxxxxx
> > http://lists.xensource.com/xen-users
> >

It seems, actually, that something has changed since the performance
seems to be restored back to the normality.

Mh, I can't explain that.. maybe I had some process keep running CPU
high while I was performing that hdparm.

I'll keep this thread up-to-date if something changes again.

Sorry for this bad report.

-- 
Fabiano Francesconi [GPG key: 0x81E53461]

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