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 D04CEC433F5 for ; Mon, 9 May 2022 13:45:58 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3893A6B0072; Mon, 9 May 2022 09:45:58 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3391F6B0073; Mon, 9 May 2022 09:45:58 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1FFA66B0074; Mon, 9 May 2022 09:45:58 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 0EC856B0072 for ; Mon, 9 May 2022 09:45:58 -0400 (EDT) Received: from smtpin05.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 9AD06611A7 for ; Mon, 9 May 2022 13:45:57 +0000 (UTC) X-FDA: 79446327954.05.3778EB3 Received: from mail-qt1-f172.google.com (mail-qt1-f172.google.com [209.85.160.172]) by imf04.hostedemail.com (Postfix) with ESMTP id 6D499400A4 for ; Mon, 9 May 2022 13:45:47 +0000 (UTC) Received: by mail-qt1-f172.google.com with SMTP id e15so10978574qtp.3 for ; Mon, 09 May 2022 06:45:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20210112.gappssmtp.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=fdtyY+76slzM1oP4DlLOabKhkAkAGRbXkU+vbbhXODI=; b=ASZyWPXF9PtMX10Dwd7rQieT8a3L+16a5mx52slrfszXDgs4xuzeCVGKZXDxgmFbvX xP8Vbz4n60V1G0p7lbKcmpOr4/RXMn39dp3bXXpKSMYf4xxmY0uZSFy29gmknYlOd0jg Q07UCLl/aYGd+vnRS+5snSd1jU/CVTUB+npodpUmxlyUNUOHNiXQYlVmhMDl5/P16ipN RtwacxeumcSaUs/89KM+tiMp2Dl6CLA67scGwmkttVV7Uvx40WybSXpAQ4p2AObPcwSX W5TkreCcvuX97pJ2o88fM8HYgmqNFB6TkunZhjoDyf5beCqpPZ24XAdhcOYGjMvDB57c khGg== 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; bh=fdtyY+76slzM1oP4DlLOabKhkAkAGRbXkU+vbbhXODI=; b=3vGxbmMJE1y68Aqrkr4I5zoFMQK5c3anIMn5rgzyo/rm/mUGek9dFQ0HNYnnMFTlBD GASSI/l1dvYy+IOZ7YQJGyUeCc34ry8pjQaiQgZuWcmjwDs7ELzmO6nn1d5/sLPG7xqX UwH0x+Pa9TYRT7P7CA6lZWRKz0KbdHzIdr6Di/ky8Sbn/ZFm8gMqa7wUibKhAfsYABX2 fiJ3bEborphBJIYBEkE1wUoiaqgBqQ6vZGzB+d1LHjuWQuaSQ+UDkSyMKVVGoAfXbuXu yIdVme9xwKpoTMXKc7uXoej3O3WMk7Z28D0lkmtfTuLMi1CC1KRe/UulsT6/1g49GrSP /CgA== X-Gm-Message-State: AOAM530n24YPZQay9UkPtCdx/hxT8hL35TWOdB/i4TjcNy6aRPfrZnTZ ln1C+ZllFgPuU5f7+Ucyn7L/jQ== X-Google-Smtp-Source: ABdhPJzKYh0T+cOT8AdJzg5vmaD+u1ezEXrU0M4bp98QI9Rk9T9vGmQ/GN9GZTVap08E/m/bVJKxgA== X-Received: by 2002:ac8:5948:0:b0:2f3:cd85:f244 with SMTP id 8-20020ac85948000000b002f3cd85f244mr11370810qtz.149.1652103955845; Mon, 09 May 2022 06:45:55 -0700 (PDT) Received: from localhost ([2620:10d:c091:480::1:538c]) by smtp.gmail.com with ESMTPSA id 18-20020a05620a06d200b0069fc13ce213sm6831521qky.68.2022.05.09.06.45.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 09 May 2022 06:45:55 -0700 (PDT) Date: Mon, 9 May 2022 09:44:58 -0400 From: Johannes Weiner To: Ganesan Rajagopal Cc: mhocko@kernel.org, roman.gushchin@linux.dev, shakeelb@google.com, cgroups@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v2] mm/memcontrol: Export memcg->watermark via sysfs for v2 memcg Message-ID: References: <20220507050916.GA13577@us192.sjc.aristanetworks.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220507050916.GA13577@us192.sjc.aristanetworks.com> X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 6D499400A4 X-Stat-Signature: fskpi63t5k9adm3ijbqptjndna6c9rg7 Authentication-Results: imf04.hostedemail.com; dkim=pass header.d=cmpxchg-org.20210112.gappssmtp.com header.s=20210112 header.b=ASZyWPXF; spf=pass (imf04.hostedemail.com: domain of hannes@cmpxchg.org designates 209.85.160.172 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (policy=none) header.from=cmpxchg.org X-HE-Tag: 1652103947-419965 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, May 06, 2022 at 10:09:16PM -0700, Ganesan Rajagopal wrote: > We run a lot of automated tests when building our software and run into > OOM scenarios when the tests run unbounded. v1 memcg exports > memcg->watermark as "memory.max_usage_in_bytes" in sysfs. We use this > metric to heuristically limit the number of tests that can run in > parallel based on per test historical data. > > This metric is currently not exported for v2 memcg and there is no > other easy way of getting this information. getrusage() syscall returns > "ru_maxrss" which can be used as an approximation but that's the max > RSS of a single child process across all children instead of the > aggregated max for all child processes. The only work around is to > periodically poll "memory.current" but that's not practical for > short-lived one-off cgroups. > > Hence, expose memcg->watermark as "memory.peak" for v2 memcg. > > Signed-off-by: Ganesan Rajagopal Acked-by: Johannes Weiner