From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: Re: [PATCH] qemu-kvm: response to SIGUSR1 to start/stop a VCPU (v2)
Date: Wed, 01 Dec 2010 18:22:56 +0100
Message-ID: <1291224176.32004.1763.camel@laptop>
References: <1290530963-3448-1-git-send-email-aliguori@us.ibm.com>
	 <4CECCA39.4060702@redhat.com> <4CED1A23.9030607@linux.vnet.ibm.com>
	 <4CED1FD3.1000801@redhat.com> <20101201123742.GA3780@linux.vnet.ibm.com>
	 <4CF6460C.5070604@redhat.com> <20101201161221.GA8073@linux.vnet.ibm.com>
	 <1291220718.32004.1696.camel@laptop>
	 <20101201171758.GA8514@sequoia.sous-sol.org>
Mime-Version: 1.0
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 8BIT
Cc: vatsa@linux.vnet.ibm.com, Avi Kivity <avi@redhat.com>,
	Anthony Liguori <aliguori@linux.vnet.ibm.com>,
	qemu-devel@nongnu.org, kvm@vger.kernel.org,
	Ingo Molnar <mingo@elte.hu>, Mike Galbraith <efault@gmx.de>,
	riel@redhat.com
To: Chris Wright <chrisw@sous-sol.org>
Return-path: <kvm-owner@vger.kernel.org>
Received: from casper.infradead.org ([85.118.1.10]:45436 "EHLO
	casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1754793Ab0LARXP convert rfc822-to-8bit (ORCPT
	<rfc822;kvm@vger.kernel.org>); Wed, 1 Dec 2010 12:23:15 -0500
In-Reply-To: <20101201171758.GA8514@sequoia.sous-sol.org>
Sender: kvm-owner@vger.kernel.org
List-ID: <kvm.vger.kernel.org>

On Wed, 2010-12-01 at 09:17 -0800, Chris Wright wrote:
> Directed yield and fairness don't mix well either. You can end up
> feeding the other tasks more time than you'll ever get back.

If the directed yield is always to another task in your cgroup then
inter-guest scheduling fairness should be maintained. 

Yes, but not the inter-vcpu fairness.