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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 45F74C433B4 for ; Wed, 7 Apr 2021 13:32:38 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id D1B5261382 for ; Wed, 7 Apr 2021 13:32:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D1B5261382 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ubuntu.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 5CAE86B007E; Wed, 7 Apr 2021 09:32:37 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 5A0B66B0080; Wed, 7 Apr 2021 09:32:37 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 490066B0081; Wed, 7 Apr 2021 09:32:37 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0144.hostedemail.com [216.40.44.144]) by kanga.kvack.org (Postfix) with ESMTP id 2BFEC6B007E for ; Wed, 7 Apr 2021 09:32:37 -0400 (EDT) Received: from smtpin18.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id B7B513638 for ; Wed, 7 Apr 2021 13:32:36 +0000 (UTC) X-FDA: 78005660712.18.1DD6F6B Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf24.hostedemail.com (Postfix) with ESMTP id 75934A0003A4 for ; Wed, 7 Apr 2021 13:32:32 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id EFA02601FB; Wed, 7 Apr 2021 13:32:32 +0000 (UTC) Date: Wed, 7 Apr 2021 15:32:30 +0200 From: Christian Brauner To: Michal Hocko , stgraber@ubuntu.com Cc: Bharata B Rao , akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, aneesh.kumar@linux.ibm.com Subject: Re: High kmalloc-32 slab cache consumption with 10k containers Message-ID: <20210407133230.6slrpyjjfrc34s7u@wittgenstein> References: <20210405054848.GA1077931@in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 75934A0003A4 X-Stat-Signature: w4rdua8mogxdjnmkkygn4r33skmd8qjn Received-SPF: none (kernel.org>: No applicable sender policy available) receiver=imf24; identity=mailfrom; envelope-from=""; helo=mail.kernel.org; client-ip=198.145.29.99 X-HE-DKIM-Result: none/none X-HE-Tag: 1617802352-344160 Content-Transfer-Encoding: quoted-printable 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 Wed, Apr 07, 2021 at 01:54:48PM +0200, Michal Hocko wrote: > On Mon 05-04-21 11:18:48, Bharata B Rao wrote: > > Hi, > >=20 > > When running 10000 (more-or-less-empty-)containers on a bare-metal Po= wer9 > > server(160 CPUs, 2 NUMA nodes, 256G memory), it is seen that memory > > consumption increases quite a lot (around 172G) when the containers a= re > > running. Most of it comes from slab (149G) and within slab, the major= ity of > > it comes from kmalloc-32 cache (102G) >=20 > Is this 10k cgroups a testing enviroment or does anybody really use tha= t > in production? I would be really curious to hear how that behaves when > those containers are not idle. E.g. global memory reclaim iterating ove= r > 10k memcgs will likely be very visible. I do remember playing with > similar setups few years back and the overhead was very high. Ccing St=C3=A9phane Graber who has experience/insight about stuff like th= is. Christian