From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755908Ab2ADO5f (ORCPT ); Wed, 4 Jan 2012 09:57:35 -0500 Received: from e7.ny.us.ibm.com ([32.97.182.137]:35131 "EHLO e7.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755796Ab2ADO5c (ORCPT ); Wed, 4 Jan 2012 09:57:32 -0500 Date: Wed, 4 Jan 2012 20:26:02 +0530 From: Srivatsa Vaddagiri To: Avi Kivity Cc: Nikunj A Dadhania , Rik van Riel , Ingo Molnar , peterz@infradead.org, linux-kernel@vger.kernel.org, bharata@linux.vnet.ibm.com Subject: Re: [RFC PATCH 0/4] Gang scheduling in CFS Message-ID: <20120104145602.GB8333@linux.vnet.ibm.com> Reply-To: Srivatsa Vaddagiri References: <4EF1B85F.7060105@redhat.com> <877h1o9dp7.fsf@linux.vnet.ibm.com> <20111223103620.GD4749@elte.hu> <4EF701C7.9080907@redhat.com> <20111230095147.GA10543@elte.hu> <878vlu4bgh.fsf@linux.vnet.ibm.com> <87pqf5mqg4.fsf@abhimanyu.in.ibm.com> <4F017AD2.3090504@redhat.com> <87mxa3zqm1.fsf@abhimanyu.in.ibm.com> <4F046536.5080207@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <4F046536.5080207@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) x-cbid: 12010414-5806-0000-0000-0000110E328A Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Avi Kivity [2012-01-04 16:41:58]: > > Here are some observation related to Baseline-only(8vm case) > > > > | ple_gap=128 | ple_gap=64 | ple_gap=256 | ple_window=2048 > > --------------+-------------+------------+-------------+---------------- > > EbzyRecords/s | 2247.50 | 2132.75 | 2086.25 | 1835.62 > > PauseExits | 7928154.00 | 6696342.00 | 7365999.00 | 50319582.00 > > > > With ple_window = 2048, PauseExits is more than 6times the default case > > So it looks like the default is optimal, at least wrt the cases you > tested and your test workload. The default case still lags considerably behind the results we are seeing with gang scheduling. One more interesting data point would be to see how many PLE exits we are seeing when the vcpu is spinning in flush_tlb_others_ipi(). Is there any easy way to determine that? - vatsa