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 1E6F5C433F5 for ; Fri, 10 Sep 2021 17:17:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F1931611C3 for ; Fri, 10 Sep 2021 17:17:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231487AbhIJRSh (ORCPT ); Fri, 10 Sep 2021 13:18:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39098 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230203AbhIJRSf (ORCPT ); Fri, 10 Sep 2021 13:18:35 -0400 Received: from mail-lj1-x22e.google.com (mail-lj1-x22e.google.com [IPv6:2a00:1450:4864:20::22e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 69068C061756 for ; Fri, 10 Sep 2021 10:17:24 -0700 (PDT) Received: by mail-lj1-x22e.google.com with SMTP id g14so4324531ljk.5 for ; Fri, 10 Sep 2021 10:17:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=nVQhctFDZ494oNwBH6gZ4cbrFJOKVOXq8XesRbY6VI8=; b=X3ZeLOv7Q89I9RQFoFeRBRpC6KFK599HOifkIv4mt+CDHlTcxp+0UZzQfGIac7s/WU su9klzfHpoo2JCuO5V6sdmD9Pjv0Son2DzEwAUYK1Fb8fESck+P/K3BB3zpVFrrzbqoq fWiP8VjGyW5ujY+25dO79xLu0fCjv0GYy1PM7qxJAFJmxBfOetkWzo/gjjGwE3rxVHqq CoLWcgmrUkPIZI87CrcDasqd8fwS5E5jtPfD9rUiYU7zpGP7aHBwySf4Ahj2YzofjZT3 sXJTf1zEDcGFkN25gOgJHiiScjdCRPauxVCQ+ZXyuaflxySs2RuMdOyrppCWX6Yp1rkc Zjcw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=nVQhctFDZ494oNwBH6gZ4cbrFJOKVOXq8XesRbY6VI8=; b=LnQe3iaDuKuZQDcDMRs2H3pdXlAsSvVFfJopPE5BxkXyJ7KSjiNXx89LC53KIpGSFn wjCoG7x66CCbGq+MJ9Rg7xC4zQn/eCN6mXJ6miO/2+JjyqwqZGM051lOAW5bm01X1tXE yiwrOtQpEu6VHxRbw0YeqNDhtKB1dFo6iCZ5rmLPA6vhgfOR1p++D8Z9tRz95usJpy0L jj5gvJNmiLilqh236uK/DMNe3Kk4BjvoRKDzh2EFNHEz/e4X48h0r1cAv9yIRp4NdkU6 mG8tnJY4QBN5PNPgtx54d2ZqNxEFjRtPmdpcRrCbYKW+5RgpjC+TwyhSdPIXRyEG474c mg+Q== X-Gm-Message-State: AOAM530ykxBFx7+yS7P5HU8zGgPsw33LzW85y4uc8B5rgPx5/VXUQ++R O4vhbEGk1D9fLar2qPYHLWMpqA4l0Dc74/Bh1a9Zvg== X-Google-Smtp-Source: ABdhPJxuSFmjJAz4+yQEFqKFceCVS/DwoXXiLxCnZRQlzKqsxH9ZXu8FjpT1qbLP2ejb4nwzXgEVms4z2EvPr/ik44Q= X-Received: by 2002:a2e:858e:: with SMTP id b14mr4949174lji.508.1631294242440; Fri, 10 Sep 2021 10:17:22 -0700 (PDT) MIME-Version: 1.0 References: <988f340462a1a3c62b7dc2c64ceb89a4c0a00552.1631077837.git.brookxu@tencent.com> <86e89df640f2b4a65dd77bdbab8152fa8e8f5bf1.1631077837.git.brookxu@tencent.com> <20210909143720.GA14709@blackbody.suse.cz> <478e986c-bc69-62b8-936e-5b075f9270b4@gmail.com> <20210910092310.GA18084@blackbody.suse.cz> <1679f995-5a6f-11b8-7870-54318db07d0d@gmail.com> <20210910153609.GC24156@blackbody.suse.cz> In-Reply-To: From: Vipin Sharma Date: Fri, 10 Sep 2021 10:16:46 -0700 Message-ID: Subject: Re: [RFC PATCH 3/3] misc_cgroup: remove error log to avoid log flood To: =?UTF-8?Q?Michal_Koutn=C3=BD?= , "brookxu.cn" Cc: Tejun Heo , lizefan.x@bytedance.com, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 10, 2021 at 9:29 AM Tejun Heo wrote: > > Hello, > > On Fri, Sep 10, 2021 at 05:36:09PM +0200, Michal Koutn=C4=B1 wrote: > > If there's a limit on certain level with otherwise unconstrained cgroup > > structure below (a valid config too), the 'fail' counter would help > > determining what the affected cgroup is. Does that make sense to you? > > While the desire to make the interface complete is understandable, I don'= t > think we need to go too far in that direction given that debugging these > configuration issues requires human intervention anyway and providing > overall information is often enough of aid especially for simple controll= ers > like misc/pid. So, let's stick to something consistent and simple even if > not complete and definitely not name them "fail" even if we add them. > I understand what Michal is proposing regarding fail vs max and local vs hierarchical. I think this will provide complete information but it will be too many interfaces for a simple controller like misc and might not even get used by anyone. Chunguang's case was to avoid printing so many messages, I agree we should remove the log message and add a file event. For now, I think we can just have one file, events.local (non-hierarchical) which has %s.max type entries. This will tell us which cgroup is under pressure and I believe this is helpful. Regarding the original cgroup which started the charge should be easier to identify because those processes will not be able to proceed or will use some alternate logic, and the job owner should be able to notice it. If in future there is a need to find the originating cgroup we can resume this discussion during that time.