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 34882C54EE9 for ; Wed, 7 Sep 2022 20:43:26 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 860FB8D0001; Wed, 7 Sep 2022 16:43:25 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 80FFC6B0073; Wed, 7 Sep 2022 16:43:25 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6D80F8D0001; Wed, 7 Sep 2022 16:43:25 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 5B27C6B0072 for ; Wed, 7 Sep 2022 16:43:25 -0400 (EDT) Received: from smtpin18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 288FA1208B6 for ; Wed, 7 Sep 2022 20:43:25 +0000 (UTC) X-FDA: 79886464770.18.35FC724 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by imf18.hostedemail.com (Postfix) with ESMTP id C299D1C0077 for ; Wed, 7 Sep 2022 20:43:24 +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 ams.source.kernel.org (Postfix) with ESMTPS id 05404B81E8E; Wed, 7 Sep 2022 20:43:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1272EC433B5; Wed, 7 Sep 2022 20:43:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1662583401; bh=FRKdhXGWFNIp4ValMgTEBtAERy/TmsP1c+r60idMAtc=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=GCuThdvvW+ISBXwN7pYF3eReAOVwGG4l8qSRElZF8x/O8rzqjZYgy60xJPEFtQ8om DZlGkg5Ynq01RnKTVK2SGLXF4JXtOcdTfvuWUeMvp4/BCPUN9JC9eT3FCGiaTIw9Yl lJwGXZ+YPsdqdsvTt9TiNPm9qou3MbrvAkcGLtp4= Date: Wed, 7 Sep 2022 13:43:20 -0700 From: Andrew Morton To: "Sun, Jiebin" Cc: Tim Chen , Shakeel Butt , vasily.averin@linux.dev, Dennis Zhou , Tejun Heo , Christoph Lameter , "Eric W. Biederman" , Alexey Gladkov , Manfred Spraul , alexander.mikhalitsyn@virtuozzo.com, Linux MM , LKML , "Chen, Tim C" , Feng Tang , Huang Ying , tianyou.li@intel.com, wangyang.guo@intel.com Subject: Re: [PATCH] ipc/msg.c: mitigate the lock contention with percpu counter Message-Id: <20220907134320.01d1693387bde4af5d3100fb@linux-foundation.org> In-Reply-To: References: <20220902152243.479592-1-jiebin.sun@intel.com> <048517e7f95aa8460cd47a169f3dfbd8e9b70d5c.camel@linux.intel.com> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit ARC-Authentication-Results: i=1; imf18.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=GCuThdvv; spf=pass (imf18.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1662583404; a=rsa-sha256; cv=none; b=JU2kTp3uryWKaIDPmB3HKZZCEqsnN/qnKqYCFTBaR7niQyqzNmgGb7YLVfEn2vBrCtrryD G1ZT4jeUPAoueasX5LEV2DxzdGRMmYsfZHqJhibcmeD0FyZrEEs3Yo0L4akfO6JKuTHzkJ wniVh0XpCr/PfRZxB+LnfCjXUw9smw0= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1662583404; 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=DqAXMu4cxUuTfBMq13EAY3qywXR4RodRp2JSfowt3Es=; b=cLdY8ci9SKcc4pGK0Z7CTyYL7XtSetreiSCeuodj0r2b8lh5ZWmvauIF/D4Q8HvOVbA2MY 1L00kngqhAauldU7wyVYUp5jXJrQH+cyeeTo9mmJwxAlyeMg3PiczhPfKizWku4BpXY6RC WjSF29GHfdFXcZf1QWSOjPnkRcN0W+8= Authentication-Results: imf18.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=GCuThdvv; spf=pass (imf18.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none X-Rspam-User: X-Rspamd-Queue-Id: C299D1C0077 X-Rspamd-Server: rspam05 X-Stat-Signature: bom8b55aox63bn9xr557peap9spt51k8 X-HE-Tag: 1662583404-723958 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 Wed, 7 Sep 2022 17:39:47 +0800 "Sun, Jiebin" wrote: > I have sent out the patch v4 which use percpu_counter_add_batch. If we use > a tuned large batch size (1024), Oh. Why not simply use a batch size of INT_MAX? > the performance gain is 3.17x (patch v4) > vs 3.38x (patch v3) previously in stress-ng -- message. It still has > significant performance improvement and also good balance between > performance gain and overflow issue.