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=-8.7 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_PASS, 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 292A0C282C0 for ; Fri, 25 Jan 2019 16:37:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E4982218B0 for ; Fri, 25 Jan 2019 16:37:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548434257; bh=Wa8YGjA70uRv8lcXPJo00o/NWb87JGR4yVBHa3yfXtA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=Ymhly3/1ZannL65N8C+5DFWbaUUtGuXb8o8ZVm/RABbczvv2JX2DJek5oAUXT9k6c EXfwVI+qC9yNh/5OKqp10vA3Qqs0H2sOOZywrfyqCOv2WAW86mc3v4rm6k8d8kYbko 01/nUFxf8C5mCXExBR+lmTHA3L6EDXAN4aj4TL2s= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728933AbfAYQhf (ORCPT ); Fri, 25 Jan 2019 11:37:35 -0500 Received: from mail-yw1-f65.google.com ([209.85.161.65]:36976 "EHLO mail-yw1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726108AbfAYQhf (ORCPT ); Fri, 25 Jan 2019 11:37:35 -0500 Received: by mail-yw1-f65.google.com with SMTP id h193so4139037ywc.4; Fri, 25 Jan 2019 08:37:34 -0800 (PST) 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:content-transfer-encoding:in-reply-to :user-agent; bh=RYL7pbha6AtxQjHD3ZK0n6qiStyqrgkMrnAlVCP0NNE=; b=hZvlbsqyaKWNVGRewUWJIxOTzlUYhWS2zbX7SH2tizlgJpQpx60Q9lFUr1KAvxcC/o 1hPJlxzXj2+3gfQcXN2m7hvMawtI4t9aj1dEem45TLpkEql/eZmnG/q1Rj1mzVyhtxwr HV7sN0Yf6DRbhWtZYwjdL3tBn7xcNcxE0m4fXAVJgEjZPCK1VAIW74UMrRR1vLSuVj0h HyosUDdb9lBIVd02NWUS0S1pWyvOPCIyUMbdo++pIUAlLLlAg3hl9wVbLnyV7iSiBQWQ Cmfs2mFJwxet2D8u3OAyjG/l6Soc19pDLR4LD+aJZAPHD4x6jylVAxQ/YGkiG692WER7 s73w== 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 :content-transfer-encoding:in-reply-to:user-agent; bh=RYL7pbha6AtxQjHD3ZK0n6qiStyqrgkMrnAlVCP0NNE=; b=grp19tW/nbo3bDcd8fRB8zEyFb5W9KxS0YOnVn/s1ox0ZLWlxXTHQcw8jmq8bwLSvA Ob54BhFhYKIaXGJSN7tzP0tiuaWt6/M+40IdoOwZmJa3JdlMHyxPfwM/19a8o8DLs1ZE dS/QUueHudkFcoRMGmJCtod0Z4p58lfps5asELBoNS2ycc/O9Vp49PIWHN6+pN1uhqIA 8tll35zCR+um61zbYM+9Xl5Xz3FsWa7A3jAGqNj5T9bu3D8VD8BoEj/zNoDqPXYD/Nit PVvPVPKwHGVFsosidfege9i1VTsnPIJ2rxWhHF4yEv7AYH5iFctskFOEFbzHQuEnJ8AS ZLYA== X-Gm-Message-State: AJcUukfo81jlbaPyyQ29tUJD48XxAyJWWcSsSd/RJRPlUmPjMYRk/KpZ prxn/9zFmmv258PupRuu9k4= X-Google-Smtp-Source: ALg8bN6sgnHZX7knHYbGpxaRfjiI2fQMJ5uI/FNsinsGrbevn28z84ir4BlsluB5YpbixjVnQSajIQ== X-Received: by 2002:a81:d845:: with SMTP id n5mr11854141ywl.486.1548434253786; Fri, 25 Jan 2019 08:37:33 -0800 (PST) Received: from localhost ([2620:10d:c091:200::7:a62a]) by smtp.gmail.com with ESMTPSA id b129sm10282016ywc.106.2019.01.25.08.37.32 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 25 Jan 2019 08:37:32 -0800 (PST) Date: Fri, 25 Jan 2019 08:37:31 -0800 From: Tejun Heo To: Arkadiusz =?utf-8?Q?Mi=C5=9Bkiewicz?= Cc: cgroups@vger.kernel.org, Aleksa Sarai , Jay Kamat , Roman Gushchin , Michal Hocko , Johannes Weiner , linux-kernel@vger.kernel.org Subject: Re: pids.current with invalid value for hours [5.0.0 rc3 git] Message-ID: <20190125163731.GJ50184@devbig004.ftw2.facebook.com> References: <20190117122535.njcbqhlmzozdkncw@mikami> <1d36b181-cbaf-6694-1a31-2f7f55d15675@gmail.com> <96ef6615-a5df-30af-b4dc-417a18ca63f1@gmail.com> <1cdbef13-564d-61a6-95f4-579d2cad243d@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1cdbef13-564d-61a6-95f4-579d2cad243d@gmail.com> 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 Fri, Jan 25, 2019 at 08:52:11AM +0100, Arkadiusz Miśkiewicz wrote: > On 24/01/2019 12:21, Arkadiusz Miśkiewicz wrote: > > On 17/01/2019 14:17, Arkadiusz Miśkiewicz wrote: > >> On 17/01/2019 13:25, Aleksa Sarai wrote: > >>> On 2019-01-17, Arkadiusz Miśkiewicz wrote: > >>>> Using kernel 4.19.13. > >>>> > >>>> For one cgroup I noticed weird behaviour: > >>>> > >>>> # cat pids.current > >>>> 60 > >>>> # cat cgroup.procs > >>>> # > >>> > >>> Are there any zombies in the cgroup? pids.current is linked up directly > >>> to __put_task_struct (so exit(2) won't decrease it, only the task_struct > >>> actually being freed will decrease it). > >>> > >> > >> There are no zombie processes. > >> > >> In mean time the problem shows on multiple servers and so far saw it > >> only in cgroups that were OOMed. > >> > >> What has changed on these servers (yesterday) is turning on > >> memory.oom.group=1 for all cgroups and changing memory.high from 1G to > >> "max" (leaving memory.max=2G limit only). > >> > >> Previously there was no such problem. > >> > > > > I'm attaching reproducer. This time tried on different distribution > > kernel (arch linux). > > > > After 60s pids.current still shows 37 processes even if there are no > > processes running (according to ps aux). > > > The same test on 5.0.0-rc3-00104-gc04e2a780caf and it's easy to > reproduce bug. No processes in cgroup but pids.current reports 91. Can you please see whether the problem can be reproduced on the current linux-next? git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git Thanks. -- tejun