From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751157AbdANOA4 (ORCPT ); Sat, 14 Jan 2017 09:00:56 -0500 Received: from smtp23.mail.ru ([94.100.181.178]:51262 "EHLO smtp23.mail.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750802AbdANOAz (ORCPT ); Sat, 14 Jan 2017 09:00:55 -0500 Date: Sat, 14 Jan 2017 17:00:43 +0300 From: Vladimir Davydov To: Tejun Heo Cc: cl@linux.com, penberg@kernel.org, rientjes@google.com, iamjoonsoo.kim@lge.com, akpm@linux-foundation.org, jsvana@fb.com, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, cgroups@vger.kernel.org, kernel-team@fb.com Subject: Re: [PATCH 9/9] slab: remove slub sysfs interface files early for empty memcg caches Message-ID: <20170114140043.GH2668@esperanza> References: <20170114055449.11044-1-tj@kernel.org> <20170114055449.11044-10-tj@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170114055449.11044-10-tj@kernel.org> Authentication-Results: smtp23.mail.ru; auth=pass smtp.auth=vdavydov@tarantool.org smtp.mailfrom=vdavydov@tarantool.org X-E1FCDC63: 26CF7C04F9023CD3C98069CA2DAC3D090DE140DF427568CF X-E1FCDC64: CD999CDA504268FBFB54C13B8D5C96FB0A4E3464D74930127D98276AA7E12C10 X-Mailru-Sender: AA5F055C295B4E99DFBD641EBD0382546D5AC5EC13193B3EB917A56C2C4092B23A11E76D10A8DA3FDDDE7B70B5F5C79F X-Mras: OK Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Jan 14, 2017 at 12:54:49AM -0500, Tejun Heo wrote: > With kmem cgroup support enabled, kmem_caches can be created and > destroyed frequently and a great number of near empty kmem_caches can > accumulate if there are a lot of transient cgroups and the system is > not under memory pressure. When memory reclaim starts under such > conditions, it can lead to consecutive deactivation and destruction of > many kmem_caches, easily hundreds of thousands on moderately large > systems, exposing scalability issues in the current slab management > code. This is one of the patches to address the issue. > > Each cache has a number of sysfs interface files under > /sys/kernel/slab. On a system with a lot of memory and transient > memcgs, the number of interface files which have to be removed once > memory reclaim kicks in can reach millions. > > Signed-off-by: Tejun Heo > Reported-by: Jay Vana > Cc: Vladimir Davydov > Cc: Christoph Lameter > Cc: Pekka Enberg > Cc: David Rientjes > Cc: Joonsoo Kim > Cc: Andrew Morton Acked-by: Vladimir Davydov