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=-2.5 required=3.0 tests=MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,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 EA212C3A5A2 for ; Tue, 10 Sep 2019 13:24:22 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id ADC1F2084D for ; Tue, 10 Sep 2019 13:24:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org ADC1F2084D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 35B056B0007; Tue, 10 Sep 2019 09:24:22 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 30C986B0008; Tue, 10 Sep 2019 09:24:22 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 221C76B000A; Tue, 10 Sep 2019 09:24:22 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0053.hostedemail.com [216.40.44.53]) by kanga.kvack.org (Postfix) with ESMTP id EEAC56B0007 for ; Tue, 10 Sep 2019 09:24:21 -0400 (EDT) Received: from smtpin07.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with SMTP id 9CEC78243768 for ; Tue, 10 Sep 2019 13:24:21 +0000 (UTC) X-FDA: 75919079922.07.cake42_7d53357cb2c29 X-HE-Tag: cake42_7d53357cb2c29 X-Filterd-Recvd-Size: 3228 Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) by imf15.hostedemail.com (Postfix) with ESMTP for ; Tue, 10 Sep 2019 13:24:21 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 99511ABCE; Tue, 10 Sep 2019 13:24:19 +0000 (UTC) Date: Tue, 10 Sep 2019 15:24:18 +0200 From: Michal Hocko To: Stefan Priebe - Profihost AG Cc: "linux-mm@kvack.org" , l.roehrs@profihost.ag, cgroups@vger.kernel.org, Johannes Weiner , Vlastimil Babka Subject: Re: lot of MemAvailable but falling cache and raising PSI Message-ID: <20190910132418.GC2063@dhcp22.suse.cz> References: <52235eda-ffe2-721c-7ad7-575048e2d29d@profihost.ag> <20190910082919.GL2063@dhcp22.suse.cz> <132e1fd0-c392-c158-8f3a-20e340e542f0@profihost.ag> <20190910090241.GM2063@dhcp22.suse.cz> <743a047e-a46f-32fa-1fe4-a9bd8f09ed87@profihost.ag> <20190910110741.GR2063@dhcp22.suse.cz> <364d4c2e-9c9a-d8b3-43a8-aa17cccae9c7@profihost.ag> <20190910125756.GB2063@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) 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 Tue 10-09-19 15:14:45, Stefan Priebe - Profihost AG wrote: > Am 10.09.19 um 15:05 schrieb Stefan Priebe - Profihost AG: > > > > Am 10.09.19 um 14:57 schrieb Michal Hocko: > >> On Tue 10-09-19 14:45:37, Stefan Priebe - Profihost AG wrote: > >>> Hello Michal, > >>> > >>> ok this might take a long time. Attached you'll find a graph from a > >>> fresh boot what happens over time (here 17 August to 30 August). Memory > >>> Usage decreases as well as cache but slowly and only over time and days. > >>> > >>> So it might take 2-3 weeks running Kernel 5.3 to see what happens. > >> > >> No problem. Just make sure to collect the requested data from the time > >> you see the actual problem. Btw. you try my very dumb scriplets to get > >> an idea of how much memory gets reclaimed due to THP. > > > > You mean your sed and sort on top of the trace file? No i did not with > > the current 5.3 kernel do you think it will show anything interesting? > > Which line shows me how much memory gets reclaimed due to THP? Please re-read http://lkml.kernel.org/r/20190910082919.GL2063@dhcp22.suse.cz Each command has a commented output. If you see nunmber of reclaimed pages to be large for GFP_TRANSHUGE then you are seeing a similar problem. > Is something like a kernel memory leak possible? Or wouldn't this end up > in having a lot of free memory which doesn't seem usable. I would be really surprised if this was the case. > I also wonder why a reclaim takes place when there is enough memory. This is not clear yet and it might be a bug that has been fixed since 4.18. That's why we need to see whether the same is pattern is happening with 5.3 as well. -- Michal Hocko SUSE Labs