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 EC9D7ECAAD8 for ; Wed, 21 Sep 2022 09:13:13 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 550C6940007; Wed, 21 Sep 2022 05:13:13 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 500A46B0073; Wed, 21 Sep 2022 05:13:13 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 41686940007; Wed, 21 Sep 2022 05:13:13 -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 32FC66B0072 for ; Wed, 21 Sep 2022 05:13:13 -0400 (EDT) Received: from smtpin06.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 06FB11C61C1 for ; Wed, 21 Sep 2022 09:13:13 +0000 (UTC) X-FDA: 79935528666.06.13A8C4D Received: from outbound-smtp24.blacknight.com (outbound-smtp24.blacknight.com [81.17.249.192]) by imf19.hostedemail.com (Postfix) with ESMTP id 9C52F1A000D for ; Wed, 21 Sep 2022 09:13:12 +0000 (UTC) Received: from mail.blacknight.com (pemlinmail03.blacknight.ie [81.17.254.16]) by outbound-smtp24.blacknight.com (Postfix) with ESMTPS id 2494BC0D35 for ; Wed, 21 Sep 2022 10:13:11 +0100 (IST) Received: (qmail 17661 invoked from network); 21 Sep 2022 09:13:11 -0000 Received: from unknown (HELO techsingularity.net) (mgorman@techsingularity.net@[84.203.198.246]) by 81.17.254.9 with ESMTPSA (AES256-SHA encrypted, authenticated); 21 Sep 2022 09:13:10 -0000 Date: Wed, 21 Sep 2022 10:13:03 +0100 From: Mel Gorman To: Hongchen Zhang Cc: Mel Gorman , Matthew Wilcox , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/vmscan: don't scan adjust too much if current is not kswapd Message-ID: <20220921091303.hihmb3qvfvl3s365@techsingularity.net> References: <20220914023318.549118-1-zhanghongchen@loongson.cn> <20220914155142.bf388515a39fb45bae987231@linux-foundation.org> <6bcb4883-03d0-88eb-4c42-84fff0a9a141@loongson.cn> <54813a74-cc0e-e470-c632-78437a0d0ad4@loongson.cn> <4bd0012e-77ff-9d0d-e295-800471994aeb@loongson.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1663751592; a=rsa-sha256; cv=none; b=rxN0PIZbY3MuZJcjVr4iuVfcTEzGbb9yVODG0n5TcT2e9I6NjXGxuiI6ZIg4pGjeeN+jZT TvT/hbIia9Gsqe8DwmIzRsBCM01yNRsUiTtzIfLSWDs1UsmvWRBVfirIt2CpsCnyVx8s3l 2nXIy7gLtmV/plrwXPD9JjxsoWquBCE= ARC-Authentication-Results: i=1; imf19.hostedemail.com; dkim=none; dmarc=none; spf=pass (imf19.hostedemail.com: domain of mgorman@techsingularity.net designates 81.17.249.192 as permitted sender) smtp.mailfrom=mgorman@techsingularity.net ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1663751592; 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: in-reply-to:in-reply-to:references:references; bh=vp4xFvk0xAYbu+cJxmPTUbzhsOoxu1Gs8L4AXSBGcRc=; b=VE8Yy6+8yLHz9Tl9AvTgawEXjiiP/vf7NmLcSWxe4wVG2vrG4fgB2XTwHFd1RbDPR1ATlQ ftOBsCRLP4kDqe1dzfBHKnPU6vVVvUjeke5Hbd9W6W8136m4DcUB3cpZcloSOR+RopAMyq jPexeLDlywhDdr1ahMPpqxb/SxFjAiM= X-Rspamd-Queue-Id: 9C52F1A000D Authentication-Results: imf19.hostedemail.com; dkim=none; dmarc=none; spf=pass (imf19.hostedemail.com: domain of mgorman@techsingularity.net designates 81.17.249.192 as permitted sender) smtp.mailfrom=mgorman@techsingularity.net X-Rspamd-Server: rspam08 X-Rspam-User: X-Stat-Signature: 4jxjbcbic8exmm6g8rp3ntzfhwejrmwb X-HE-Tag: 1663751592-31911 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 Tue, Sep 20, 2022 at 10:23:05AM +0800, Hongchen Zhang wrote: > Hi Mel, > > The scan adjust algorithm was originally introduced by you from > commmit e82e0561dae9 ("mm: vmscan: obey proportional scanning requirements > for kswapd"), any suggestion about this fix patch? > In short, proportional scanning is not friendly to processes other than > kswapd. > I suspect that 6eb90d649537 ("mm: vmscan: fix extreme overreclaim and swap floods") is a more appropriate fix. While it also has a fairness impact, it's a more general approach that is likely more robust and while fairness is important, completely thrashing a full LRU is neither fair nor expected. -- Mel Gorman SUSE Labs