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 6B555C433F5 for ; Fri, 17 Dec 2021 07:40:57 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id CB17E6B0073; Fri, 17 Dec 2021 02:40:46 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id C61856B0075; Fri, 17 Dec 2021 02:40:46 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B50486B0078; Fri, 17 Dec 2021 02:40:46 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0196.hostedemail.com [216.40.44.196]) by kanga.kvack.org (Postfix) with ESMTP id A16806B0073 for ; Fri, 17 Dec 2021 02:40:46 -0500 (EST) Received: from smtpin31.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 5BA9C180C1219 for ; Fri, 17 Dec 2021 07:40:36 +0000 (UTC) X-FDA: 78926488872.31.D41BBC2 Received: from out4436.biz.mail.alibaba.com (out4436.biz.mail.alibaba.com [47.88.44.36]) by imf08.hostedemail.com (Postfix) with ESMTP id B1E0416000E for ; Fri, 17 Dec 2021 07:40:30 +0000 (UTC) X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R191e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04394;MF=baolin.wang@linux.alibaba.com;NM=1;PH=DS;RN=17;SR=0;TI=SMTPD_---0V-t9ojA_1639726819; Received: from 30.21.164.42(mailfrom:baolin.wang@linux.alibaba.com fp:SMTPD_---0V-t9ojA_1639726819) by smtp.aliyun-inc.com(127.0.0.1); Fri, 17 Dec 2021 15:40:20 +0800 Message-ID: <907015a0-43f8-3ab4-524b-9c867d1f06d8@linux.alibaba.com> Date: Fri, 17 Dec 2021 15:41:05 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.4.0 Subject: Re: [PATCH -V10 RESEND 3/6] memory tiering: skip to scan fast memory To: Huang Ying , Peter Zijlstra , Mel Gorman Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Feng Tang , Dave Hansen , Andrew Morton , Michal Hocko , Rik van Riel , Mel Gorman , Yang Shi , Zi Yan , Wei Xu , osalvador , Shakeel Butt , Hasan Al Maruf References: <20211207022757.2523359-1-ying.huang@intel.com> <20211207022757.2523359-4-ying.huang@intel.com> From: Baolin Wang In-Reply-To: <20211207022757.2523359-4-ying.huang@intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: B1E0416000E X-Stat-Signature: qycd3fogxxsopq7gjmrjzoksamcrdgy4 Authentication-Results: imf08.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=alibaba.com; spf=pass (imf08.hostedemail.com: domain of baolin.wang@linux.alibaba.com designates 47.88.44.36 as permitted sender) smtp.mailfrom=baolin.wang@linux.alibaba.com X-Rspamd-Server: rspam11 X-HE-Tag: 1639726830-340432 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 12/7/2021 10:27 AM, Huang Ying wrote: > If the NUMA balancing isn't used to optimize the page placement among > sockets but only among memory types, the hot pages in the fast memory > node couldn't be migrated (promoted) to anywhere. So it's unnecessary > to scan the pages in the fast memory node via changing their PTE/PMD > mapping to be PROT_NONE. So that the page faults could be avoided > too. > > In the test, if only the memory tiering NUMA balancing mode is enabled, the > number of the NUMA balancing hint faults for the DRAM node is reduced to > almost 0 with the patch. While the benchmark score doesn't change > visibly. > > Signed-off-by: "Huang, Ying" > Suggested-by: Dave Hansen > Cc: Andrew Morton > Cc: Michal Hocko > Cc: Rik van Riel > Cc: Mel Gorman > Cc: Peter Zijlstra > Cc: Yang Shi > Cc: Zi Yan > Cc: Wei Xu > Cc: osalvador > Cc: Shakeel Butt > Cc: Hasan Al Maruf > Cc: linux-kernel@vger.kernel.org > Cc: linux-mm@kvack.org > --- LGTM. Please feel free to add: Tested-by: Baolin Wang Reviewed-by: Baolin Wang