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 59133CA9EA0 for ; Tue, 22 Oct 2019 13:28:05 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 30BEA21783 for ; Tue, 22 Oct 2019 13:28:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 30BEA21783 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 CC4B46B0007; Tue, 22 Oct 2019 09:28:04 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C75176B0008; Tue, 22 Oct 2019 09:28:04 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B8BCC6B000A; Tue, 22 Oct 2019 09:28:04 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0204.hostedemail.com [216.40.44.204]) by kanga.kvack.org (Postfix) with ESMTP id 988236B0007 for ; Tue, 22 Oct 2019 09:28:04 -0400 (EDT) Received: from smtpin15.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with SMTP id 38BFA52A4 for ; Tue, 22 Oct 2019 13:28:04 +0000 (UTC) X-FDA: 76071498888.15.dolls19_809c5d6b08117 X-HE-Tag: dolls19_809c5d6b08117 X-Filterd-Recvd-Size: 2072 Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) by imf20.hostedemail.com (Postfix) with ESMTP for ; Tue, 22 Oct 2019 13:28:03 +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 6EB55ACA0; Tue, 22 Oct 2019 13:28:02 +0000 (UTC) Date: Tue, 22 Oct 2019 15:28:00 +0200 From: Michal Hocko To: Roman Gushchin Cc: linux-mm@kvack.org, Johannes Weiner , linux-kernel@vger.kernel.org, kernel-team@fb.com, Shakeel Butt , Vladimir Davydov , Waiman Long , Christoph Lameter Subject: Re: [PATCH 00/16] The new slab memory controller Message-ID: <20191022132800.GO9379@dhcp22.suse.cz> References: <20191018002820.307763-1-guro@fb.com> <20191022132206.GN9379@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191022132206.GN9379@dhcp22.suse.cz> 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 22-10-19 15:22:06, Michal Hocko wrote: > On Thu 17-10-19 17:28:04, Roman Gushchin wrote: > [...] > > Using a drgn* script I've got an estimation of slab utilization on > > a number of machines running different production workloads. In most > > cases it was between 45% and 65%, and the best number I've seen was > > around 85%. Turning kmem accounting off brings it to high 90s. Also > > it brings back 30-50% of slab memory. It means that the real price > > of the existing slab memory controller is way bigger than a pointer > > per page. > > How much of the memory are we talking about here? Just to be more specific. Your cover mentions several hundreds of MBs but there is no scale to the overal charged memory. How much of that is the actual kmem accounted memory. > Also is there any pattern for specific caches that tend to utilize > much worse than others? -- Michal Hocko SUSE Labs