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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, 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 C6053C3A5AA for ; Thu, 5 Sep 2019 12:27:18 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9664B22DBF for ; Thu, 5 Sep 2019 12:27:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9664B22DBF Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=profihost.ag Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 27D8F6B029A; Thu, 5 Sep 2019 08:27:18 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 22D8D6B029B; Thu, 5 Sep 2019 08:27:18 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 143CA6B029C; Thu, 5 Sep 2019 08:27:18 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0004.hostedemail.com [216.40.44.4]) by kanga.kvack.org (Postfix) with ESMTP id E7D316B029A for ; Thu, 5 Sep 2019 08:27:17 -0400 (EDT) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with SMTP id 6A6D3181AC9AE for ; Thu, 5 Sep 2019 12:27:17 +0000 (UTC) X-FDA: 75900792114.05.crush23_3f91c93ff2640 X-HE-Tag: crush23_3f91c93ff2640 X-Filterd-Recvd-Size: 2498 Received: from cloud1-vm154.de-nserver.de (cloud1-vm154.de-nserver.de [178.250.10.56]) by imf27.hostedemail.com (Postfix) with ESMTP for ; Thu, 5 Sep 2019 12:27:16 +0000 (UTC) Received: (qmail 16449 invoked from network); 5 Sep 2019 14:27:15 +0200 X-Fcrdns: No Received: from phoffice.de-nserver.de (HELO [10.242.2.4]) (185.39.223.5) (smtp-auth username hostmaster@profihost.com, mechanism plain) by cloud1-vm154.de-nserver.de (qpsmtpd/0.92) with (ECDHE-RSA-AES256-GCM-SHA384 encrypted) ESMTPSA; Thu, 05 Sep 2019 14:27:15 +0200 Subject: Re: lot of MemAvailable but falling cache and raising PSI To: Vlastimil Babka , "linux-mm@kvack.org" Cc: l.roehrs@profihost.ag, cgroups@vger.kernel.org, Johannes Weiner , Michal Hocko References: <4b4ba042-3741-7b16-2292-198c569da2aa@profihost.ag> <5c1d6fca-4bbe-1c09-e0c5-523bca8fbb6a@suse.cz> From: Stefan Priebe - Profihost AG Message-ID: <7379c903-3a46-a1b0-0903-ce03c982226a@profihost.ag> Date: Thu, 5 Sep 2019 14:27:14 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <5c1d6fca-4bbe-1c09-e0c5-523bca8fbb6a@suse.cz> Content-Type: text/plain; charset=utf-8 Content-Language: de-DE Content-Transfer-Encoding: 7bit X-User-Auth: Auth by hostmaster@profihost.com through 185.39.223.5 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: Am 05.09.19 um 14:15 schrieb Vlastimil Babka: > On 9/5/19 1:27 PM, Stefan Priebe - Profihost AG wrote: >> Hello all, >> >> i hope you can help me again to understand the current MemAvailable >> value in the linux kernel. I'm running a 4.19.52 kernel + psi patches in >> this case. >> >> I'm seeing the following behaviour i don't understand and ask for help. >> >> While MemAvailable shows 5G the kernel starts to drop cache from 4G down >> to 1G while the apache spawns some PHP processes. After that the PSI >> mem.some value rises and the kernel tries to reclaim memory but >> MemAvailable stays at 5G. >> >> Any ideas? > > PHP seems to use madvise(MADV_HUGEPAGE), so if it's a NUMA machine it > might be worth trying to cherry-pick these two commits: > 92717d429b38 ("Revert "Revert "mm, thp: consolidate THP gfp handling > into alloc_hugepage_direct_gfpmask""") > a8282608c88e ("Revert "mm, thp: restore node-local hugepage allocations"") No it's a vm running inside qemu/kvm without numa. Greets, Stefan