From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 83E2DC433E2 for ; Fri, 28 Aug 2020 06:48:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5DDF820825 for ; Fri, 28 Aug 2020 06:48:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="C3It3OAM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726714AbgH1GsG (ORCPT ); Fri, 28 Aug 2020 02:48:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40586 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725858AbgH1GsF (ORCPT ); Fri, 28 Aug 2020 02:48:05 -0400 Received: from mail-lj1-x242.google.com (mail-lj1-x242.google.com [IPv6:2a00:1450:4864:20::242]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BD604C061264 for ; Thu, 27 Aug 2020 23:48:04 -0700 (PDT) Received: by mail-lj1-x242.google.com with SMTP id h19so74991ljg.13 for ; Thu, 27 Aug 2020 23:48:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=oydfEDC6u3iLPJyfxYWLejhiNpsHmSRRREzeNSIlIRg=; b=C3It3OAMIxBXfjvtUb92LHDBEbsc8n58DTyxKK9cDKU4Ye4zVK5uS/JCPFRogMVJHX o//Kwj5VcD6LPAzrUumD3SiTTfifFbbv/fKOC6A8VbktoBVdxwXroyokYvzPJ4Bri+fT JHgeX8pk5ruqmApjgkqBuX5vGnhKWLzHq+oqAakhK08W6rHs4f8RXtHzJZ6exzENkJE6 0UcvJrQYM1w0y2gs2i9/7asXNxCjwwc6jLGFRjvV9CMiMZz0q8XN4++Y9/1fYSs+KGe/ TGPkGsas5qil/QezclbRSTBYphwu23e+x4KxLcldPEZNcG6omF3ucX9JNe68U2eXn4ky SA0A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=oydfEDC6u3iLPJyfxYWLejhiNpsHmSRRREzeNSIlIRg=; b=G4ryJZGI+s93KafofUTlvRk7izU85o/TdY6vIyWwhuRZd+MuCW96emPD+ngdCgpIgM v3tgbj6qo8fSsX7pt7Y9+7Yen8vlQIv3z51DOqAfpLi/XxfiRGCyVCPqrRqfAhHCwe9s sdXwAQOF5rkm1gfLqOq66zodmMyppcsbqGqEImWbFwnful7XK5W1J8eNRnpdlqipq77J SmKHCIOXHumjbK04fIREB2ZztItnr4Tz3b0TViNCC1Y50th/nr+DOcH1nkbM/Vr9Kqv5 wfTjVlUA3vItTu1MrTapjZdCS06MPNUyecV+H6d9/wItqhoPyxpmeTq/xw3jAz4YMm8L yXjA== X-Gm-Message-State: AOAM531joO/zvHVeCXK/z8vxEZD5COg23d6Eoi650PMYeqZnLVCAboVi aie3Lr65mtq5V2j2aRSdh9WGIgDOCSVNbPgDdFrmLZdKEG8= X-Google-Smtp-Source: ABdhPJz9D0alYTdnFqLYQJf4VVhnGovaO4fFvjApYM8uFElaR82ulVJpdJ9fv+pCi/o85KyTPHk4MX7Y261OxNOKT/0= X-Received: by 2002:a2e:9812:: with SMTP id a18mr194440ljj.25.1598597283126; Thu, 27 Aug 2020 23:48:03 -0700 (PDT) MIME-Version: 1.0 References: <20200825121818.30260-1-vincent.guittot@linaro.org> <20200827153534.GF3033@suse.de> <20200827182221.GG3033@suse.de> In-Reply-To: <20200827182221.GG3033@suse.de> From: Vincent Guittot Date: Fri, 28 Aug 2020 08:47:51 +0200 Message-ID: Subject: Re: [PATCH] sched/numa: use runnable_avg to classify node To: Mel Gorman Cc: Ingo Molnar , Peter Zijlstra , Juri Lelli , Dietmar Eggemann , Steven Rostedt , Ben Segall , linux-kernel Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 27 Aug 2020 at 20:22, Mel Gorman wrote: > > On Thu, Aug 27, 2020 at 05:43:11PM +0200, Vincent Guittot wrote: > > > The testing was a mixed bag of wins and losses but wins more than it > > > loses. Biggest loss was a 9.04% regression on nas-SP using openmp for > > > parallelisation on Zen1. Biggest win was around 8% gain running > > > specjbb2005 on Zen2 (with some major gains of up to 55% for some thread > > > counts). Most workloads were stable across multiple Intel and AMD > > > machines. > > > > > > There were some oddities in changes in NUMA scanning rate but that is > > > likely a side-effect because the locality over time for the same loads > > > did not look obviously worse. There was no negative result I could point > > > at that was not offset by a positive result elsewhere. Given it's not > > > a univeral win or loss, matching numa and lb balancing as closely as > > > possible is best so > > > > > > Reviewed-by: Mel Gorman > > > > Thanks. > > > > I will try to reproduce the nas-SP test on my setup to see what is going one > > > > You can try but you might be chasing ghosts. Please note that this nas-SP > observation was only on zen1 and only for C-class and OMP. The other > machines tested for the same class and OMP were fine (including zen2). Even > D-class on the same machine with OMP was fine as was MPI in both cases. The > bad result indicated that NUMA scanning and faulting was higher but that > is more likely to be a problem with NUMA balancing than your patch. > > In the five iterations, two iterations showed a large spike in scan rate > towards the end of an iteration but not the other three. The scan rate > was also not consistently high so there is a degree of luck involved with > SP specifically and there is not a consistently penalty as a result of > your patch. > > The only thing to be aware of is that this patch might show up in > bisections once it's merged for both performance gains and losses. Thanks for the detailed explanation. I will save my time and continue on the fairness problem in this case. Vincent > > -- > Mel Gorman > SUSE Labs