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


[Xen-devel] qemu cpu utility too high as dom0 cpu stealtime's also high

To: xen-devel@xxxxxxxxxxxxxxxxxxx
Subject: [Xen-devel] qemu cpu utility too high as dom0 cpu stealtime's also high
From: alice wan <wanjia19870902@xxxxxxxxx>
Date: Fri, 10 Jun 2011 21:57:13 +0800
Delivery-date: Fri, 10 Jun 2011 06:59:20 -0700
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:date:message-id:subject:from:to :content-type; bh=mOdiu9L/XyY3lzHvM/zbfEmUpOmTimcezu4D51RJEXc=; b=te67xGC45A5ZbfJVBkORt8wUKCN6JJVTVKNlK6Kl5xQXtQcUKhftFCaFSs56owj/GG kLuRZg1On1SKCj6DPXGw9pUC9e8U38OQoP1yFX9LoFJM5fsImxRST49zmzOFMf1WY/Yd veYD5WhUXYUU7VqNLMLl+RR1e+3DV5wEPvwGw=
Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:content-type; b=rFWu2w9rkCOwyKmDWUFTccoNDbSUYYDBly9/E90ADv8h7pgScmoiAq7PP+TQ2Ws0yM JK2ailvgfvmpDF6J9lynhnpKFLHfWZJOpAxqEx+nmefTjTCMgK4SRg75ZLAjkchxOkr3 Bh6TpczG8BCeFjS/7EI5RDp2VkVHld2IOIcsY=
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
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/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
hi all,
       when i started 10 windows vms of 4 vcpu on the host with 8 cpu, dom0 has 4 shareble vcpu, i found qemu-dm cpu utility is too high, about 80-90%, lasting for more than half an hour. after a long period of time, the dom0 became normal.
        i observed that when qemu-dm %cpu's too high, the dom0 cpu's stealtime was also too high.
        when dom0 became normal, %st  and qemu %cpu also became low.
        high stealtime is reasonable as the cpu is too busy, the time vcpu wait for cpu scheduling  is too long.
        however, qemu high cpu utility is unreasonable,  the oprofile report of qemu seems normal.
        I doubt the granularity of task cpu time accounting seems too rough.
        It seems that task cpu accounting didn't distinguish virtual cpu time from cpu time so that  the qemu-dm cpu time = real cpu time+steal time
        Does the task cpu accounting is based on tick?
        the config about accounting 's like this:
        # CONFIG_IRQ_TIME_ACCOUNTING is not set
        Should i turn on the CONFIG_IRQ_TIME_ACCOUNTING ?
        Any advice is appreciated, thanks in advance.
Xen-devel mailing list
<Prev in Thread] Current Thread [Next in Thread>
  • [Xen-devel] qemu cpu utility too high as dom0 cpu stealtime's also high, alice wan <=