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=-0.7 required=3.0 tests=FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 83EF2C4BA0B for ; Wed, 26 Feb 2020 10:51:58 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 087E424688 for ; Wed, 26 Feb 2020 10:51:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 087E424688 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=sina.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 6EE9D6B0003; Wed, 26 Feb 2020 05:51:56 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 6A26B6B0005; Wed, 26 Feb 2020 05:51:56 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5B5986B0006; Wed, 26 Feb 2020 05:51:56 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0038.hostedemail.com [216.40.44.38]) by kanga.kvack.org (Postfix) with ESMTP id 40BD96B0003 for ; Wed, 26 Feb 2020 05:51:56 -0500 (EST) Received: from smtpin18.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id E3005499610 for ; Wed, 26 Feb 2020 10:51:55 +0000 (UTC) X-FDA: 76531963032.18.love80_2dc0fdfe17e59 X-HE-Tag: love80_2dc0fdfe17e59 X-Filterd-Recvd-Size: 2633 Received: from r3-18.sinamail.sina.com.cn (r3-18.sinamail.sina.com.cn [202.108.3.18]) by imf39.hostedemail.com (Postfix) with SMTP for ; Wed, 26 Feb 2020 10:51:54 +0000 (UTC) Received: from unknown (HELO localhost.localdomain)([114.246.226.1]) by sina.com with ESMTP id 5E564DC300031FA3; Wed, 26 Feb 2020 18:51:49 +0800 (CST) X-Sender: hdanton@sina.com X-Auth-ID: hdanton@sina.com X-SMAIL-MID: 74633115073614 From: Hillf Danton To: Shakeel Butt Cc: Sultan Alsawaf , Mel Gorman , Dave Hansen , Andrew Morton , Linux MM , LKML Subject: Re: [PATCH] mm: Stop kswapd early when nothing's waiting for it to free pages Date: Wed, 26 Feb 2020 18:51:37 +0800 Message-Id: <20200226105137.9088-1-hdanton@sina.com> In-Reply-To: <20200225090945.GJ22443@dhcp22.suse.cz> References: <20200219194006.GA3075@sultan-book.localdomain> <20200219200527.GF11847@dhcp22.suse.cz> <20200219204220.GA3488@sultan-book.localdomain> <20200219214513.GL3420@suse.de> <20200219224231.GA5190@sultan-book.localdomain> <20200220101945.GN3420@suse.de> <20200221042232.GA2197@sultan-book.localdomain> <20200221080737.GK20509@dhcp22.suse.cz> <20200221210824.GA3605@sultan-book.localdomain> <20200225090945.GJ22443@dhcp22.suse.cz> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable 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, 25 Feb 2020 14:30:03 -0800 Shakeel Butt wrote: >=20 > BTW we are seeing a similar situation in our production environment. > We have swappiness=3D0, no swap from kswapd (because we don't swapout o= n > pressure, only on cold age) and too few file pages, the kswapd goes > crazy on shrink_slab and spends 100% cpu on it. Dunno if swappiness is able to put peace on your kswapd. --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2631,8 +2631,14 @@ static inline bool should_continue_recla */ pages_for_compaction =3D compact_gap(sc->order); inactive_lru_pages =3D node_page_state(pgdat, NR_INACTIVE_FILE); - if (get_nr_swap_pages() > 0) - inactive_lru_pages +=3D node_page_state(pgdat, NR_INACTIVE_ANON); + do { + struct lruvec *lruvec =3D mem_cgroup_lruvec(sc->target_mem_cgroup, pgd= at); + struct mem_cgroup *memcg =3D lruvec_memcg(lruvec); + int swappiness =3D mem_cgroup_swappiness(memcg); + + if (swappiness && get_nr_swap_pages() > 0) + inactive_lru_pages +=3D node_page_state(pgdat, NR_INACTIVE_ANON); + } while (0); =20 return inactive_lru_pages > pages_for_compaction; }