From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f170.google.com (mail-wi0-f170.google.com [209.85.212.170]) by kanga.kvack.org (Postfix) with ESMTP id AA9C66B00F2 for ; Mon, 3 Nov 2014 16:06:17 -0500 (EST) Received: by mail-wi0-f170.google.com with SMTP id q5so7144350wiv.1 for ; Mon, 03 Nov 2014 13:06:17 -0800 (PST) Received: from jenni2.inet.fi (mta-out1.inet.fi. [62.71.2.227]) by mx.google.com with ESMTP id as6si16082856wjc.147.2014.11.03.13.06.16 for ; Mon, 03 Nov 2014 13:06:16 -0800 (PST) Date: Mon, 3 Nov 2014 23:06:07 +0200 From: "Kirill A. Shutemov" Subject: Re: [patch 1/3] mm: embed the memcg pointer directly into struct page Message-ID: <20141103210607.GA24091@node.dhcp.inet.fi> References: <1414898156-4741-1-git-send-email-hannes@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1414898156-4741-1-git-send-email-hannes@cmpxchg.org> Sender: owner-linux-mm@kvack.org List-ID: To: Johannes Weiner Cc: Andrew Morton , Michal Hocko , Vladimir Davydov , Tejun Heo , David Miller , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org On Sat, Nov 01, 2014 at 11:15:54PM -0400, Johannes Weiner wrote: > Memory cgroups used to have 5 per-page pointers. To allow users to > disable that amount of overhead during runtime, those pointers were > allocated in a separate array, with a translation layer between them > and struct page. > > There is now only one page pointer remaining: the memcg pointer, that > indicates which cgroup the page is associated with when charged. The > complexity of runtime allocation and the runtime translation overhead > is no longer justified to save that *potential* 0.19% of memory. How much do you win by the change? -- Kirill A. Shutemov -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org