From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754526Ab1A3OEx (ORCPT ); Sun, 30 Jan 2011 09:04:53 -0500 Received: from mx1.redhat.com ([209.132.183.28]:7860 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753504Ab1A3OEw (ORCPT ); Sun, 30 Jan 2011 09:04:52 -0500 Message-ID: <4D456FF9.2010309@redhat.com> Date: Sun, 30 Jan 2011 16:04:41 +0200 From: Avi Kivity User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.13) Gecko/20101209 Fedora/3.1.7-0.35.b3pre.fc14 Lightning/1.0b3pre Thunderbird/3.1.7 MIME-Version: 1.0 To: Glauber Costa CC: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, aliguori@us.ibm.com, Rik van Riel , Jeremy Fitzhardinge , Peter Zijlstra Subject: Re: [PATCH v2 3/6] KVM-GST: KVM Steal time accounting References: <1296244340-15173-1-git-send-email-glommer@redhat.com> <1296244340-15173-4-git-send-email-glommer@redhat.com> In-Reply-To: <1296244340-15173-4-git-send-email-glommer@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/28/2011 09:52 PM, Glauber Costa wrote: > This patch accounts steal time time in kernel/sched. > I kept it from last proposal, because I still see advantages > in it: Doing it here will give us easier access from scheduler > variables such as the cpu rq. The next patch shows an example of > usage for it. > > Since functions like account_idle_time() can be called from > multiple places, not only account_process_tick(), steal time > grabbing is repeated in each account function separatedely. > I accept that steal time is worthwhile, but do you have some way to demonstrate that the implementation actually works and is beneficial? Perhaps run two cpu-bound compute processes on one vcpu, overcommit that vcpu, and see what happens to the processing rate with and without steal time accounting. I'd expect a fairer response with steal time accounting. -- error compiling committee.c: too many arguments to function