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 9E743C433EF for ; Sat, 4 Dec 2021 09:37:11 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B74DB6B007E; Sat, 4 Dec 2021 04:37:00 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id B23EF6B0080; Sat, 4 Dec 2021 04:37:00 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9EBB46B0081; Sat, 4 Dec 2021 04:37:00 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0189.hostedemail.com [216.40.44.189]) by kanga.kvack.org (Postfix) with ESMTP id 8ED676B007E for ; Sat, 4 Dec 2021 04:37:00 -0500 (EST) Received: from smtpin03.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 314FB8993F for ; Sat, 4 Dec 2021 09:36:50 +0000 (UTC) X-FDA: 78879607380.03.3DE0C31 Received: from mail-wm1-f53.google.com (mail-wm1-f53.google.com [209.85.128.53]) by imf09.hostedemail.com (Postfix) with ESMTP id D2B07300010A for ; Sat, 4 Dec 2021 09:36:50 +0000 (UTC) Received: by mail-wm1-f53.google.com with SMTP id k37-20020a05600c1ca500b00330cb84834fso6739784wms.2 for ; Sat, 04 Dec 2021 01:36:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chrisdown.name; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=Fa6xeDSp50/P8rOL+C54lxIGIVulHb+9yCsfNo1/Wpw=; b=FWWeWvzsX0lVcVoLsRisdgMqOjZy/JOgW6iYDCzNR3aS7WRsMEBPIai+ZFNIuMynAr BT2jMNkIswwTyxFGrp3xMLb/eXReYAVYgdBy/v3oHKfoEgRChUczwjAU2SBhL9tXhriA MJOvZgEQz3GgTo7U+U9Zs7ICijCpUjoRP6E8g= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=Fa6xeDSp50/P8rOL+C54lxIGIVulHb+9yCsfNo1/Wpw=; b=b+O0wsbLtLDuud/IS1FMFaNbQxjwrMuEEygkJbMJsOXbvek6/XCb2e4FOscIvEcYuI H9UhoTuVqagzCybHFZXLZf1Esopogrkr7Qig64tniB0OiEn/yK6KTYHK3DYiBE0jl5Ox 84jCKuL1MPzaEMuSZqk++QAckBzgD1+sOjo/OKbvkqnAEfUsrFGoMWN+iMF/IJkNtOkh rVWhTtxUi7/n74ZEKt3HgzeoNv74p2RvA8HcCOXba/s/I0kiTlhEkur5iR2hA6IpMsmI jRDul+szNybO1NxQdUz7f/v23I/FusRyzA+Ahfpcxs2oMc4bFw2HkhfjVL2iRc3kf/zu eIRA== X-Gm-Message-State: AOAM533M7Cq3LeNEAGplg6YY1eYc3SfM/y0aZKiX4I9rstGAEbsTdHwp GfdEMG4Mt4QOsu6nzQLw7T7C+w== X-Google-Smtp-Source: ABdhPJwiOTmQCn38xCf3cLyyJfvN07htPUbre2qVQ4wfsE4L4QKy64fvmr02+djFj6Wlf0GKZ/75tw== X-Received: by 2002:a7b:c301:: with SMTP id k1mr22029998wmj.36.1638610608329; Sat, 04 Dec 2021 01:36:48 -0800 (PST) Received: from localhost ([2a01:4b00:8432:8a00:5ee4:2aff:fe50:f48d]) by smtp.gmail.com with ESMTPSA id i17sm5622892wmq.48.2021.12.04.01.36.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 04 Dec 2021 01:36:47 -0800 (PST) Date: Sat, 4 Dec 2021 09:36:46 +0000 From: Chris Down To: Dan Schatzberg Cc: Johannes Weiner , Roman Gushchin , Tejun Heo , Zefan Li , Jonathan Corbet , Michal Hocko , Vladimir Davydov , Andrew Morton , Shakeel Butt , "Matthew Wilcox (Oracle)" , Muchun Song , Alex Shi , Wei Yang , "open list:CONTROL GROUP (CGROUP)" , "open list:DOCUMENTATION" , open list , "open list:CONTROL GROUP - MEMORY RESOURCE CONTROLLER (MEMCG)" Subject: Re: [PATCH] mm: add group_oom_kill memory event Message-ID: References: <20211203162426.3375036-1-schatzberg.dan@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20211203162426.3375036-1-schatzberg.dan@gmail.com> User-Agent: Mutt/2.1.3 (987dde4c) (2021-09-10) X-Stat-Signature: h8zybcgmc3wsenjbcu7i4wzmspspj9ey Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=chrisdown.name header.s=google header.b=FWWeWvzs; spf=pass (imf09.hostedemail.com: domain of chris@chrisdown.name designates 209.85.128.53 as permitted sender) smtp.mailfrom=chris@chrisdown.name; dmarc=pass (policy=none) header.from=chrisdown.name X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: D2B07300010A X-HE-Tag: 1638610610-972714 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: Dan Schatzberg writes: >Our container agent wants to know when a container exits if it was OOM >killed or not to report to the user. We use memory.oom.group = 1 to >ensure that OOM kills within the container's cgroup kill >everything. Existing memory.events are insufficient for knowing if >this triggered: > >1) Our current approach reads memory.events oom_kill and reports the >container was killed if the value is non-zero. This is erroneous in >some cases where containers create their children cgroups with >memory.oom.group=1 as such OOM kills will get counted against the >container cgroup's oom_kill counter despite not actually OOM killing >the entire container. > >2) Reading memory.events.local will fail to identify OOM kills in leaf >cgroups (that don't set memory.oom.group) within the container cgroup. > >This patch adds a new oom_group_kill event when memory.oom.group >triggers to allow userspace to cleanly identify when an entire cgroup >is oom killed. > >Signed-off-by: Dan Schatzberg Thanks! Acking with one minor point on the documentation front. Acked-by: Chris Down >--- > Documentation/admin-guide/cgroup-v2.rst | 4 ++++ > include/linux/memcontrol.h | 1 + > mm/memcontrol.c | 5 +++++ > mm/oom_kill.c | 1 + > 4 files changed, 11 insertions(+) > >diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst >index 2aeb7ae8b393..eec830ce2068 100644 >--- a/Documentation/admin-guide/cgroup-v2.rst >+++ b/Documentation/admin-guide/cgroup-v2.rst >@@ -1268,6 +1268,10 @@ PAGE_SIZE multiple when read back. > The number of processes belonging to this cgroup > killed by any kind of OOM killer. > >+ oom_group_kill >+ The number of times all tasks in the cgroup were killed >+ due to memory.oom.group. Maybe pedantic, but this reads as unclear to me whether in cgroup with 3 tasks we get the value "3" or "1" when a group kill occurs. Maybe rephrase to not make be about tasks and just say "number of times a group OOM occurred"?