[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] CAP and performance problem

  • To: Massimo Canonico <mex@xxxxxxxxxxxx>
  • From: Juergen Gross <juergen.gross@xxxxxxxxxxxxxx>
  • Date: Thu, 06 Jun 2013 12:39:08 +0200
  • Cc: George Dunlap <George.Dunlap@xxxxxxxxxxxxx>, Dario Faggioli <dario.faggioli@xxxxxxxxxx>, xen-devel@xxxxxxxxxxxxx
  • Delivery-date: Thu, 06 Jun 2013 10:39:29 +0000
  • Domainkey-signature: s=s1536a; d=ts.fujitsu.com; c=nofws; q=dns; h=X-SBRSScore:X-IronPort-AV:Received:X-IronPort-AV: Received:Message-ID:Date:From:Organization:User-Agent: MIME-Version:To:CC:Subject:References:In-Reply-To: Content-Type:Content-Transfer-Encoding; b=rag7fZweEXK00c48q2s+TN6xgdiPSedpozBzvsM6Y03pgJHhnUO/w/ql aeYzTlapRxg/FUJNXnRJ0elY41X9/+Xbge/c8ZtksQbyV4MFRc5KWI1Hd JnrTVZCy65BrwlUm4DtMb3n6BHJxmB652aduLsy1RaCIurYqwEZt4OP8v q7H2+jUCyUCmIADHQ7GfrplNhlBv8w0SKzG+IrHhhLqSfdLTOdJRDV85/ CreTFu+bt/5TZND/A+qGx9eGj9EoM;
  • List-id: Xen developer discussion <xen-devel.lists.xen.org>

On 06.06.2013 10:57, Massimo Canonico wrote:

On 06/06/2013 10:37 AM, Dario Faggioli wrote:
On mer, 2013-06-05 at 19:05 +0200, Massimo Canonico wrote:
Hi Dario,
and thanks for these test.

I forgot to ask you which xen version has beed used for your experiments.

Yeah, me too! :-)

I'm using xen-unstable, pulled yesterday (commit id
e430510e5cbbfcdc1077739292def633e70fedea), compiled and installed on a
Debian unstable system. Dom0 kernel is a bit old, as it's a 3.6.

What about you?
xen 4.2.2
kernel dom0: 3.8.11-200.fc18.x86_64

Just had an idea: is there any other load on the system during your test (other
domains, dom0 load)? If not, it could be that the power management is reducing
the cpu speed during idle (when the cap applies). This could lead to reduced
performance overall.

You can test this by setting the xen hypervisor boot option


and run your test again (with and without cap).


Juergen Gross                 Principal Developer Operating Systems
PBG PDG ES&S SWE OS6                   Telephone: +49 (0) 89 3222 2967
Fujitsu Technology Solutions              e-mail: juergen.gross@xxxxxxxxxxxxxx
Domagkstr. 28                           Internet: ts.fujitsu.com
D-80807 Muenchen                 Company details: ts.fujitsu.com/imprint.html

Xen-devel mailing list



Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.