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=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 6B942CA9EA0 for ; Fri, 18 Oct 2019 11:58:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4380021852 for ; Fri, 18 Oct 2019 11:58:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=codeblueprint-co-uk.20150623.gappssmtp.com header.i=@codeblueprint-co-uk.20150623.gappssmtp.com header.b="HFD3g+Y6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404538AbfJRL6x (ORCPT ); Fri, 18 Oct 2019 07:58:53 -0400 Received: from mail-wr1-f65.google.com ([209.85.221.65]:45143 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392487AbfJRL6x (ORCPT ); Fri, 18 Oct 2019 07:58:53 -0400 Received: by mail-wr1-f65.google.com with SMTP id q13so981798wrs.12 for ; Fri, 18 Oct 2019 04:58:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=codeblueprint-co-uk.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=3DByddWkc5cdTXqfZ8p4x/nfiNubhnhdBlB/o+i+ezM=; b=HFD3g+Y6OPB8fRJSvhg77Uh3VrsobKCLs+qlqxAsDrwyyaIR1S28n2tEgpMGmME3N1 eSC8Y5L4spPuKlYR8IDXqVqPNkE3wCI57nEpQix5fZ1YSbdbMHfNnJ2PpqBII60CfCEy Ok14KMQdXroVK9EVkaLhU/WnvCdAn0n9Yah3KkgBKAeK6jWnnL950i+rFk0vvprF+Kgl VqJvd/gOuFEwIWQMsWaydU/DXQuhWBkZ7YMJEinq57kTrYMMSQMVXzK9KiODoYDMp4BE FlsEC7VTKImLcUvhnKjXjyBaTk5xpaLL5zLi8eShGH+77khULSLWGpfm6eAmW0CvOW3c TUUg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=3DByddWkc5cdTXqfZ8p4x/nfiNubhnhdBlB/o+i+ezM=; b=ncbv3OG4r3lf4CPWhA34x/7VohemlUGM0LYmbvqPe9XL7U7goVkzq3/aHpov9ck8KK ViM0wv9H7TTbFLue4ucnSWGfnDnkGjpJJKlBAINjRl61dJS598Ubh4I9DmLWnlBf9Dgf EuISJW8MucH3Y9bgPfMCaaldhi8W4nQSFpmdVvNCO4Xzthnt2jifPagUo8m3HsA2+h4s TCHpt/vAM+enRjMtTixbh3SIfF2ajtzUenjAOkYlxmTede4BSPF32ZZxZj1+AKhQ3dMW JncjCVK8z02UQeOhVmsdWlHhFP1b3Cdafx26mT5/ILQ0sPfz6mH9pqV8OWAVs2j0+Gvy JR/Q== X-Gm-Message-State: APjAAAVL0TvyBS4h9AMcQWVY/O4q4j5qESJLxgQ4/CLqS53SUi/6nAg9 t7Ev/lo6xpXRVdZmvT6CNuwim83YrZ0= X-Google-Smtp-Source: APXvYqzdh7H6730oJvDIxHy9u1G9t2x+96YrbWxez+zHkilicBfh+IJpTmhTpIA8Xbhv6dcEfu+6hg== X-Received: by 2002:a5d:638b:: with SMTP id p11mr7031669wru.372.1571399931236; Fri, 18 Oct 2019 04:58:51 -0700 (PDT) Received: from localhost (97e34ace.skybroadband.com. [151.227.74.206]) by smtp.gmail.com with ESMTPSA id a204sm6947970wmh.21.2019.10.18.04.58.50 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 18 Oct 2019 04:58:50 -0700 (PDT) Date: Fri, 18 Oct 2019 12:58:49 +0100 From: Matt Fleming To: Mel Gorman Cc: Andrew Morton , Michal Hocko , Vlastimil Babka , Thomas Gleixner , Borislav Petkov , Linux-MM , Linux Kernel Mailing List Subject: Re: [PATCH 0/3] Recalculate per-cpu page allocator batch and high limits after deferred meminit Message-ID: <20191018115849.GH4065@codeblueprint.co.uk> References: <20191018105606.3249-1-mgorman@techsingularity.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191018105606.3249-1-mgorman@techsingularity.net> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 18 Oct, at 11:56:03AM, Mel Gorman wrote: > A private report stated that system CPU usage was excessive on an AMD > EPYC 2 machine while building kernels with much longer build times than > expected. The issue is partially explained by high zone lock contention > due to the per-cpu page allocator batch and high limits being calculated > incorrectly. This series addresses a large chunk of the problem. Patch 1 > is mostly cosmetic but prepares for patch 2 which is the real fix. Patch > 3 is definiely cosmetic but was noticed while implementing the fix. Proper > details are in the changelog for patch 2. > > include/linux/mm.h | 3 --- > mm/internal.h | 3 +++ > mm/page_alloc.c | 33 ++++++++++++++++++++------------- > 3 files changed, 23 insertions(+), 16 deletions(-) Just to confirm, these patches don't fix the issue we're seeing on the EPYC 2 machines, but they do return the batch sizes to sensible values.