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=-5.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham 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 D90F2C31E50 for ; Sat, 15 Jun 2019 16:20:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A71B62184B for ; Sat, 15 Jun 2019 16:20:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560615610; bh=JN32MerifTHCEK05QgjXMgwAkP5I5Nm64MhOiNcGLIw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=ABuFyw1fcF/tueIBgDN5lxe7dEatQp5DmAyMng0CR0RWuZpt9820bNBtjZMp+EjwE bmxE9cFN471nCyIYIKokP21eVovdosj1wCTR4Oo+2cHNmS0K60dm6LJQZils9JnNhc SpwRsYo2QfFuxSlxXNdA1aoGsabQUvydXSnTWPJA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726935AbfFOQUJ (ORCPT ); Sat, 15 Jun 2019 12:20:09 -0400 Received: from mail-qt1-f196.google.com ([209.85.160.196]:41553 "EHLO mail-qt1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726770AbfFOQUJ (ORCPT ); Sat, 15 Jun 2019 12:20:09 -0400 Received: by mail-qt1-f196.google.com with SMTP id d17so1168881qtj.8; Sat, 15 Jun 2019 09:20:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=eX2SsF5NLCHpL5vWayCPj5W8iQ02n38k3DDKs0RQPsc=; b=r+pPrVqAooiurT+r/1q1YOmCwatUD8JpCV7NTTno22ito/5zCfh0NLhl4iMS76Apur od3597crTGgH49Iea/iv0Hn+0dlF/nDVBakGN4yUlzBbBCV7oNn3R/Bmj4uooW+AvzSq CoDrMHiPzNMxHFiIA2AVcMJEvoDu3Sre8J0jWQfHXmstDyO/JzqBUfsw3itDzLJSBcrs ygygJfj+TtVYs+wlFzjkcpQDIS/nIKFEb6axYc6x/QK0djwkF2fCJNAc/y61BV3vka5B 8mAN5LXYOY+ViRwZe6TnrbIBxANgmaxXVVIjq7dZoY1LghPPCg6/kI93rpDyZAqEeGiF eErw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=eX2SsF5NLCHpL5vWayCPj5W8iQ02n38k3DDKs0RQPsc=; b=bHLE+hhJeQZtg7O3aDuwX5PK63mfytxyqOB+l/udIFIr4IuRJnRPOey6wbShHUcIrg g/d88WXsLclyvTXHIP6HHfZUr6j9DmqXfYJlMZ+/ocBUXZDt8PMMY1AY602LXWDJVMKY U1ZuJuwiOY7JCGa1VOAM+xCTDnmvPT6HAAXSJz3qfDyy+2JgN976+UEhNYNmo2kmvV4g ndl5u31mz7IK+FyGx+Jp7eo//3vklXMnVpq4H+zwxKF/Xa58hUKeu8CarOtQoeJnt4zo GaKzG6ByCjgk9OZt4btGgZUrabXY5MqNjw2Ms5Ketxho+YxEuhdtykUq7CZdr9lQJo6u PKGQ== X-Gm-Message-State: APjAAAWjK6OsiaC5hOVb2LtUW12CfbrkdnjvvSF22n6q1O6FIYw5PsYk JJv33sxZTdjeypslCGOIYWM= X-Google-Smtp-Source: APXvYqzYKArsrn7PLBHxWCNzaRPRtCR+Ia5hnnBaEJfJot7DPD4U31BQXQuIuLwjHEBGGLC6yj+Wdw== X-Received: by 2002:ac8:1e15:: with SMTP id n21mr59570805qtl.20.1560615607770; Sat, 15 Jun 2019 09:20:07 -0700 (PDT) Received: from localhost ([2620:10d:c091:480::673a]) by smtp.gmail.com with ESMTPSA id 5sm3807720qkr.68.2019.06.15.09.20.06 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 15 Jun 2019 09:20:06 -0700 (PDT) Date: Sat, 15 Jun 2019 09:20:04 -0700 From: Tejun Heo To: Xi Ruoyao Cc: Johannes Weiner , Michal Hocko , Vladimir Davydov , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, dschatzberg@fb.com Subject: Re: [PATCH RFC] mm: memcontrol: add cgroup v2 interface to read memory watermark Message-ID: <20190615162004.GG657710@devbig004.ftw2.facebook.com> References: <0f1be041f8de95603753ffe989bd25069efa13bb.camel@mengyan1223.wang> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0f1be041f8de95603753ffe989bd25069efa13bb.camel@mengyan1223.wang> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Jun 15, 2019 at 04:20:04PM +0800, Xi Ruoyao wrote: > Introduce a control file memory.watermark showing the watermark > consumption of the cgroup and its descendants, in bytes. > > Signed-off-by: Xi Ruoyao Memory usage w/o pressure metric isn't all that useful and reporting just the historical maximum of memory.current can be outright misleading. The use case of determining maximum amount of required memory is legit but it needs to maintain sustained positive pressure while taking measurements. There are efforts on this front, so let's not merge this one for now. Nacked-by: Tejun Heo Thanks. -- tejun