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=-5.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 88C0AC433E1 for ; Tue, 18 Aug 2020 10:18:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 62AC6204EA for ; Tue, 18 Aug 2020 10:18:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chrisdown.name header.i=@chrisdown.name header.b="s4u3GuRF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726736AbgHRKSF (ORCPT ); Tue, 18 Aug 2020 06:18:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40152 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726495AbgHRKSB (ORCPT ); Tue, 18 Aug 2020 06:18:01 -0400 Received: from mail-qt1-x841.google.com (mail-qt1-x841.google.com [IPv6:2607:f8b0:4864:20::841]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DCD49C061344 for ; Tue, 18 Aug 2020 03:17:59 -0700 (PDT) Received: by mail-qt1-x841.google.com with SMTP id c12so14704350qtn.9 for ; Tue, 18 Aug 2020 03:17:59 -0700 (PDT) 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=m1d0Rse+qIi8qOmerhrf+MBXKELTuAtcs3p/xFrqf9w=; b=s4u3GuRFjGb61CKAXSbV1lMqnOMke9WVYpJMh0BBQqdPfrVKbnnOMGI9JvyBbgPm6e x6rVvOlI1ANNxy8+m3bcc1IECDj2KsJGcWVy2WR+CvANx/bwNtWdEoEKDgNVzfp3pHop hA9rOJBnJ6hFK8QUbuzjs02965lEQZmkx0qyA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=m1d0Rse+qIi8qOmerhrf+MBXKELTuAtcs3p/xFrqf9w=; b=KTGFy6D82uX+g2fTylFViiVSyJg//aryWtOh8MfgfgcZrttG67K7PGNJiGKO4x5of+ NDgtcdxJjupN5+Y9iBIVQM7fno5Sf0URUSIr69lz+faSe7l50CMQrWAT3ViKobRsua0m ykdjvJGlIBq+bea42Gt/Miq+MoQMqsmaJgzh1we5vboVHNv8w9eHlS8s9oXGyOceQXrh i/KG7YwG9zjrN+CGCBMjXehwoSnE1fRyiZlNqEj2vPst0ulWBA12VX8dqqTYYOFG6vra JEwt1wkfCuhfNiFZWpb3X3JiHdK8SXoPoAEXqE97twKZR2d95Q/s+tYTDyNiiVTKBe4u GXdw== X-Gm-Message-State: AOAM533xTwbF8OC/22otVNtUlblqXIB0NAnSyzoGbYZydWemw8q2hmzo rc8ooOIBGHRgNCNjsC5pLsi0yA== X-Google-Smtp-Source: ABdhPJwu2U26qaTDnNyVaIc78vhIlLEidrEGudHY3cyjqUjwF2jv5oW0015yCO0u1NOmZFEU8PeD0g== X-Received: by 2002:ac8:65c2:: with SMTP id t2mr16990912qto.370.1597745878056; Tue, 18 Aug 2020 03:17:58 -0700 (PDT) Received: from localhost ([2620:10d:c091:480::1:179c]) by smtp.gmail.com with ESMTPSA id w1sm20614419qkj.90.2020.08.18.03.17.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Aug 2020 03:17:57 -0700 (PDT) Date: Tue, 18 Aug 2020 11:17:56 +0100 From: Chris Down To: peterz@infradead.org Cc: Michal Hocko , Waiman Long , Andrew Morton , Johannes Weiner , Vladimir Davydov , Jonathan Corbet , Alexey Dobriyan , Ingo Molnar , Juri Lelli , Vincent Guittot , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org Subject: Re: [RFC PATCH 0/8] memcg: Enable fine-grained per process memory control Message-ID: <20200818101756.GA155582@chrisdown.name> References: <20200817140831.30260-1-longman@redhat.com> <20200818091453.GL2674@hirez.programming.kicks-ass.net> <20200818092617.GN28270@dhcp22.suse.cz> <20200818095910.GM2674@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20200818095910.GM2674@hirez.programming.kicks-ass.net> User-Agent: Mutt/1.14.6 (2020-07-11) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org peterz@infradead.org writes: >But then how can it run-away like Waiman suggested? Probably because he's not running with that commit at all. We and others use this to prevent runaway allocation on a huge range of production and desktop use cases and it works just fine. >/me goes look... and finds MEMCG_MAX_HIGH_DELAY_JIFFIES. > >That's a fail... :-( I'd ask that you understand a bit more about the tradeoffs and intentions of the patch before rushing in to declare its failure, considering it works just fine :-) Clamping the maximal time allows the application to take some action to remediate the situation, while still being slowed down significantly. 2 seconds per allocation batch is still absolutely plenty for any use case I've come across. If you have evidence it isn't, then present that instead of vague notions of "wrongness".