From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 96380606DD
Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=fail (p=none dis=none) header.from=linux.vnet.ibm.com
Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1752010AbeFFM6s (ORCPT <rfc822;monsieuricon@codeaurora.org>
        + 25 others); Wed, 6 Jun 2018 08:58:48 -0400
Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:45864 "EHLO
        mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL)
        by vger.kernel.org with ESMTP id S1751907AbeFFM6r (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Wed, 6 Jun 2018 08:58:47 -0400
Date: Wed, 6 Jun 2018 05:58:39 -0700
From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
To: Mel Gorman <mgorman@techsingularity.net>
Cc: Ingo Molnar <mingo@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Rik van Riel <riel@surriel.com>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH 11/19] sched/numa: Restrict migrating in parallel to the
 same node.
Reply-To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
References: <1528106428-19992-1-git-send-email-srikar@linux.vnet.ibm.com>
 <1528106428-19992-12-git-send-email-srikar@linux.vnet.ibm.com>
 <20180605095359.bbutr4psfyepdd4k@techsingularity.net>
MIME-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1
Content-Disposition: inline
In-Reply-To: <20180605095359.bbutr4psfyepdd4k@techsingularity.net>
User-Agent: Mutt/1.5.24 (2015-08-30)
X-TM-AS-GCONF: 00
x-cbid: 18060612-0020-0000-0000-00000297C05F
X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused
x-cbparentid: 18060612-0021-0000-0000-000020E3CEE7
Message-Id: <20180606125839.GA20331@linux.vnet.ibm.com>
X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-06-06_05:,,
 signatures=0
X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501
 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0
 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0
 mlxlogscore=513 adultscore=0 classifier=spam adjust=0 reason=mlx
 scancount=1 engine=8.0.1-1805220000 definitions=main-1806060150
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

> > The commit does cause some performance regression but is needed from
> > a fairness/correctness perspective.
> > 
> 
> While it may cause some performance regressions, it may be due to either
> a) some workloads benefit from overloading a node if the tasks idle
> frequently or b) the regression may be due to delayed convergence. I'm
> not 100% convinced this needs to be done from a correctness point of
> view based on just this microbenchmark
> 

I will get back with Specjbb2005 numbers as suggested by Rik.