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=-13.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 DC91FC4338F for ; Sat, 7 Aug 2021 05:24:04 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id B232E61159 for ; Sat, 7 Aug 2021 05:24:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org B232E61159 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 286166B006C; Sat, 7 Aug 2021 01:24:03 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 235698D0001; Sat, 7 Aug 2021 01:24:03 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 123216B0072; Sat, 7 Aug 2021 01:24:03 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0053.hostedemail.com [216.40.44.53]) by kanga.kvack.org (Postfix) with ESMTP id EAA9D6B006C for ; Sat, 7 Aug 2021 01:24:02 -0400 (EDT) Received: from smtpin37.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 927B78249980 for ; Sat, 7 Aug 2021 05:24:02 +0000 (UTC) X-FDA: 78447143124.37.DB3B41E Received: from mail-lf1-f47.google.com (mail-lf1-f47.google.com [209.85.167.47]) by imf02.hostedemail.com (Postfix) with ESMTP id 5561970088C5 for ; Sat, 7 Aug 2021 05:24:02 +0000 (UTC) Received: by mail-lf1-f47.google.com with SMTP id p38so22347548lfa.0 for ; Fri, 06 Aug 2021 22:24:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=ZqLuhYgeKsDqWSkoQoYju4RuNI8asvlPSwM2IzFO9Fo=; b=svcPRaGPcibReGcJQX+H6QEohG/XfPy6C4LUhMRFPhJh96e9BmeeibzkJRw4ZjY1mR bj9zeWWjVelGDg2HjiK8364mXmS4h6JPB4cXYUp+FTRFDt/ywfQa8Tw3qhwR9oB86ikQ Q9YcR8ZLzyhR/pjuyuCwKwByfJ5VhiVidPbQrqoWHUl3v3qgAJhuKUxhYDvYanGMRtAu dMLO7ngzUxE8krTsaofMQrH2Rk9SgoHmNijDRCWnj2miXffPDAMJquWYU7ZwFz1iEqFS OHUVf2vYXMXpVT8jYC39Opw57CIMRXDkBmubvdpA3mq0AD3DLxJTKK2c0eojcu0qgIxV WaQg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=ZqLuhYgeKsDqWSkoQoYju4RuNI8asvlPSwM2IzFO9Fo=; b=Vr1L5qtbPAz0qnMTIlM3nS2acpg3mmifZHiPRG5QQXVCpgrk2teGxgHs3FdOFyH4ob zQrWuofJ48YUKw/9Qu3t3gtdh6B5T4LGuo+gU1hgZvSfDEnuYKbGarbFoonwLC7frt9W 3MizEDaks6F8leD+wEsGIaj/NUoiL8j9SfUW8woNKKFOEtCBrTs1zcj19WyT6tlqseV/ d0/rv5myyOMiJE3qN7WwAvyrnmmjy2Qft7qQKx3XA2dGc6GKIkI7C25vUkrK40kU+EYq J2JC9kuJQaCVffv/33pYFb0RPV5hDp7PKEbQ6MV5WWDrUoviRbRE8LclzOCqutw1/cPj QjiA== X-Gm-Message-State: AOAM530rwY6Ka2l8DIQaWsLKUATug3JXuSg3gcs2ee8Jt7eYoUFcdJml ejVhipquAxN3TyrN8T4mHm1iFfVgyCvUfFlUqfqUIg== X-Google-Smtp-Source: ABdhPJxdoadSOx3CDgngRPDA+viNO0fADRiTs6/EPBW/zvuM5Awj/9LY2isJL4+CnvMx//QCQNg+7EYunVVFPZ1FF6E= X-Received: by 2002:a05:6512:376d:: with SMTP id z13mr5726308lft.347.1628313840113; Fri, 06 Aug 2021 22:24:00 -0700 (PDT) MIME-Version: 1.0 References: <20210806231701.106980-1-npache@redhat.com> <91605888-e343-2712-c097-bcade4cb389d@redhat.com> In-Reply-To: <91605888-e343-2712-c097-bcade4cb389d@redhat.com> From: Shakeel Butt Date: Fri, 6 Aug 2021 22:23:48 -0700 Message-ID: Subject: Re: [PATCH] vm_swappiness=0 should still try to avoid swapping anon memory To: Nico Pache Cc: Linux MM , Andrew Morton , LKML , Johannes Weiner , Rafael Aquini , Waiman Long Content-Type: text/plain; charset="UTF-8" X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 5561970088C5 Authentication-Results: imf02.hostedemail.com; dkim=pass header.d=google.com header.s=20161025 header.b=svcPRaGP; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf02.hostedemail.com: domain of shakeelb@google.com designates 209.85.167.47 as permitted sender) smtp.mailfrom=shakeelb@google.com X-Stat-Signature: uyx6rzzumjsezksnqgzsi9dtudtsm8kh X-HE-Tag: 1628313842-464366 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 Fri, Aug 6, 2021 at 6:37 PM Nico Pache wrote: > > > On 8/6/21 9:00 PM, Shakeel Butt wrote: [...] > > If you are really seeing the said behavior then why will this fix it. > > This is just about deactivating active anon LRU. I would rather look > > at get_scan_count() to check why swappiness = 0 is still letting the > > kernel to scan anon LRU. BTW in cgroup v1, the memcg can overwrite > > their swappiness which will be preferred over system vm_swappiness. > > Did you set system level swappiness or memcg one? > > This fixes the issue because shrink_list() uses the may_deactivate field > to determine if it should shrink the active list. First, the shrink_list() will not be called for anon LRU if get_scan_count() has decided to not scan the anon LRU. Second, I would like to get your attention to the following comment in get_scan_count(): "Global reclaim will swap to prevent OOM even with no swappiness" It seems like the behavior you are seeing is actually working as intended. You may decide to change that behavior but you will need to motivate the change.