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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id F2FFCC04AA5 for ; Thu, 25 Aug 2022 00:33:35 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 40ECE6B0074; Wed, 24 Aug 2022 20:33:35 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3BEB8940008; Wed, 24 Aug 2022 20:33:35 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 28650940007; Wed, 24 Aug 2022 20:33:35 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 157E66B0074 for ; Wed, 24 Aug 2022 20:33:35 -0400 (EDT) Received: from smtpin17.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id DD8EC40BFF for ; Thu, 25 Aug 2022 00:33:34 +0000 (UTC) X-FDA: 79836241548.17.9B0A8DD Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf19.hostedemail.com (Postfix) with ESMTP id 94AE31A0019 for ; Thu, 25 Aug 2022 00:33:33 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6124961A3C; Thu, 25 Aug 2022 00:33:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 40059C433C1; Thu, 25 Aug 2022 00:33:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1661387611; bh=3yxsP6DawL5+lHuusAb977k18cNkRTLfgXocBtYSv1o=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=oGJkgMPUbZFMjG8O/7KdMb+vxZpJH+5niJeB5INpD8x3qYjLkUAwWFAEXr5JNN1eo Zvf29lZuGkCpHP0RE/bBdynwQoc8oxWiELrbP6kyLDky2jSG7ggF/8yGnTB04Gjxo1 pMFYLznoGdT4pFmceHv0wgl291f+JjhUcTezFMoo= Date: Wed, 24 Aug 2022 17:33:30 -0700 From: Andrew Morton To: Shakeel Butt Cc: Johannes Weiner , Michal Hocko , Roman Gushchin , Muchun Song , =?ISO-8859-1?Q?"Michal_Koutn=FD"?= , Eric Dumazet , Soheil Hassas Yeganeh , Feng Tang , Oliver Sang , lkp@lists.01.org, cgroups@vger.kernel.org, linux-mm@kvack.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 2/3] mm: page_counter: rearrange struct page_counter fields Message-Id: <20220824173330.2a15bcda24d2c3c248bc43c7@linux-foundation.org> In-Reply-To: <20220825000506.239406-3-shakeelb@google.com> References: <20220825000506.239406-1-shakeelb@google.com> <20220825000506.239406-3-shakeelb@google.com> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1661387613; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=ONEcyKjd/1YsynyUJ/3eK8rbRU4p+goi2fdomh5cpD0=; b=hpVuFMLHLaWrGcWA/Qcn9j3MqTgpJ4DD0loMFaJlEfRm4uEG3Gi9T3EGEJcxi76zc2IyU2 8CyRzRqLNPP8L73whm0cfij68amp/dSj/+pah+eX8/RDsP39NRoeXDAWorDbLiKfrsOLm1 jvQA5KSeNvAfC6kmfI8ndCGtXT5GBMM= ARC-Authentication-Results: i=1; imf19.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=oGJkgMPU; spf=pass (imf19.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1661387613; a=rsa-sha256; cv=none; b=nTmCGbkZUv8y72UHD5l3n53GC6NoeAaKz/kNdYutmtQME23QkcmuYaPvXhkTG0N1GB0q1a w3xWEfP/fo1sV2bljomziySfTGrav4HLxUVnfvvDwcrUsXLFiHWjt5moihr8bgy/o174ej C4zo25p9fE1FXzxVYXznVH9uman+i8w= X-Stat-Signature: pyfzp4jxesih4xyhxc5r5t7xcepyhwh1 X-Rspamd-Queue-Id: 94AE31A0019 Authentication-Results: imf19.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=oGJkgMPU; spf=pass (imf19.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none X-Rspam-User: X-Rspamd-Server: rspam03 X-HE-Tag: 1661387613-166638 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, 25 Aug 2022 00:05:05 +0000 Shakeel Butt wrote: > With memcg v2 enabled, memcg->memory.usage is a very hot member for > the workloads doing memcg charging on multiple CPUs concurrently. > Particularly the network intensive workloads. In addition, there is a > false cache sharing between memory.usage and memory.high on the charge > path. This patch moves the usage into a separate cacheline and move all > the read most fields into separate cacheline. > > To evaluate the impact of this optimization, on a 72 CPUs machine, we > ran the following workload in a three level of cgroup hierarchy. > > $ netserver -6 > # 36 instances of netperf with following params > $ netperf -6 -H ::1 -l 60 -t TCP_SENDFILE -- -m 10K > > Results (average throughput of netperf): > Without (6.0-rc1) 10482.7 Mbps > With patch 12413.7 Mbps (18.4% improvement) > > With the patch, the throughput improved by 18.4%. > > One side-effect of this patch is the increase in the size of struct > mem_cgroup. For example with this patch on 64 bit build, the size of > struct mem_cgroup increased from 4032 bytes to 4416 bytes. However for > the performance improvement, this additional size is worth it. In > addition there are opportunities to reduce the size of struct > mem_cgroup like deprecation of kmem and tcpmem page counters and > better packing. Did you evaluate the effects of using a per-cpu counter of some form?