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=-6.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 60895C433DB for ; Mon, 15 Mar 2021 19:36:56 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id F2A9264F47 for ; Mon, 15 Mar 2021 19:36:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F2A9264F47 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 7D4596B006C; Mon, 15 Mar 2021 15:36:55 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7AB466B0070; Mon, 15 Mar 2021 15:36:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 674B16B0071; Mon, 15 Mar 2021 15:36:55 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0173.hostedemail.com [216.40.44.173]) by kanga.kvack.org (Postfix) with ESMTP id 49DB86B006C for ; Mon, 15 Mar 2021 15:36:55 -0400 (EDT) Received: from smtpin09.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id EF4BF52CC for ; Mon, 15 Mar 2021 19:36:54 +0000 (UTC) X-FDA: 77923116348.09.363143F Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf08.hostedemail.com (Postfix) with ESMTP id 81FAC801B2B4 for ; Mon, 15 Mar 2021 19:35:18 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 02D9164F4B; Mon, 15 Mar 2021 19:35:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1615836917; bh=WTbVaWsn2s6L40UENjvSIP12aHJ+ixP4fEvzAyMwqdw=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=V9U3lx/SRExGNl7ANONDuDDsz1cwP6og9RBlgLxmJt4k6lsk1KW4zl7F7oRpdv2nI 1lCuP+7sRGjGRZ1gh1PMqr+vBmkB1hVIS0vinUPxFxHHMG4m3Pqyo7xXdsp1GbConZ 20Jx7Xmza4070aeJBRf+7t6pE0A4G7/1szsLQPfbQeDtIziTdk9WJvsAGx4BlCRViu SZeUccNGREYMqlurXWLft5HmfWpoDq6LJL0xay+tWxTqEWaHQ0Iv20WitZOf4fJ+6k 1onK0XWAcycey/B3fS9UfoxB7glddVb7fmYZLbIt0hv7HHBQ7nLA6YJVGjVaD+i0EC OXgVmxXknEk8Q== Date: Mon, 15 Mar 2021 12:35:16 -0700 From: Jakub Kicinski To: Roman Gushchin Cc: Shakeel Butt , Vasily Averin , Cgroups , Michal Hocko , Linux MM , Johannes Weiner , Vladimir Davydov , "David S. Miller" , Hideaki YOSHIFUJI , David Ahern Subject: Re: [PATCH v2 1/8] memcg: accounting for fib6_nodes cache Message-ID: <20210315123516.6264ba0c@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> In-Reply-To: References: <85b5f428-294b-af57-f496-5be5fddeeeea@virtuozzo.com> <20210315100942.3cc98bb4@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: etofbb4ucf7grik54ysz5zkpfxe4yd4o X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 81FAC801B2B4 Received-SPF: none (kernel.org>: No applicable sender policy available) receiver=imf08; identity=mailfrom; envelope-from=""; helo=mail.kernel.org; client-ip=198.145.29.99 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1615836918-304659 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 Mon, 15 Mar 2021 12:32:07 -0700 Roman Gushchin wrote: > On Mon, Mar 15, 2021 at 12:24:31PM -0700, Shakeel Butt wrote: > > On Mon, Mar 15, 2021 at 10:09 AM Jakub Kicinski wrote: > > > Sorry for a random question, I didn't get the cover letter. > > > > > > What's the overhead of adding SLAB_ACCOUNT? > > > > The potential overhead is for MEMCG users where we need to > > charge/account each allocation from SLAB_ACCOUNT kmem caches. However > > charging is done in batches, so the cost is amortized. If there is a > > concern about a specific workload then it would be good to see the > > impact of this patch for that workload. > > > > > Please make sure you CC netdev on series which may impact networking. > > In general the overhead is not that big, so I don't think we should argue > too much about every new case where we want to enable the accounting and > rather focus on those few examples (if any?) where it actually hurts > the performance in a meaningful way. Ack, no serious concerns about this particular case. I was expecting you'd have micro benchmark numbers handy so I was curious to learn what they are, but that appears not to be the case.