Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758214AbZD1J53 (ORCPT ); Tue, 28 Apr 2009 05:57:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753137AbZD1J5T (ORCPT ); Tue, 28 Apr 2009 05:57:19 -0400 Received: from mail-bw0-f163.google.com ([209.85.218.163]:37297 "EHLO mail-bw0-f163.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751693AbZD1J5S convert rfc822-to-8bit (ORCPT ); Tue, 28 Apr 2009 05:57:18 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=REPaOmTdqDJJeUcez3kzmM6sqkp4THk/ZVO2dOI2TTWtHcRs/DvAipAsfmWHcqCvfw RDt4/ovkbbdedTRv0oqFtVz4mgdRo7Q0wsbU0ytHrccQ5n8abjKtt2b8Mh0pR5WtKECd o1l5McJkigDsUTL/k9C/40PYKVIxxPcGDTgRw= MIME-Version: 1.0 In-Reply-To: <20090428093621.GD21085@elte.hu> References: <20090428010907.912554629@intel.com> <20090428014920.769723618@intel.com> <20090428065507.GA2024@elte.hu> <20090428074031.GK27382@one.firstfloor.org> <1240909484.1982.16.camel@penberg-laptop> <20090428091508.GA21085@elte.hu> <84144f020904280219p197d5ceag846ae9a80a76884e@mail.gmail.com> <84144f020904280225h490ef682p8973cb1241a1f3ea@mail.gmail.com> <20090428093621.GD21085@elte.hu> Date: Tue, 28 Apr 2009 12:57:16 +0300 X-Google-Sender-Auth: c9c6a1668093f733 Message-ID: <84144f020904280257j57b5b686k91cc4096a8e5ca29@mail.gmail.com> Subject: Re: [PATCH 5/5] proc: export more page flags in /proc/kpageflags From: Pekka Enberg To: Ingo Molnar Cc: Andi Kleen , Wu Fengguang , Steven Rostedt , =?ISO-8859-1?Q?Fr=E9d=E9ric_Weisbecker?= , Larry Woodman , Peter Zijlstra , Eduard - Gabriel Munteanu , Andrew Morton , LKML , KOSAKI Motohiro , Matt Mackall , Alexey Dobriyan , "linux-mm@kvack.org" Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1433 Lines: 40 Hi Ingo, On Tue, Apr 28, 2009 at 12:36 PM, Ingo Molnar wrote: > I 'integrate' traces all the time to get summary counts. This series > of dynamic events: > > ?allocation > ?page count up > ?page count up > ?page count down > ?page count up > ?page count up > ?page count up > ?page count up > > integrates into: "page count is 6". > > Note that "integration" can be done wholly in the kernel too, > without going to the overhead of streaming all dynamic events to > user-space, just to summarize data into counts, in-kernel. That is > what the ftrace statistics framework and various ftrace plugins are > about. > > Also, it might make sense to extend the framework with a series of > 'get current object state' events when tracing is turned on. A > special case of _that_ would in essence be what the /proc hack does > now - just expressed in a much more generic, and a much more usable > form. I guess the main question here is whether this approach will scale to something like kmalloc() or the page allocator in production environments. For any serious workload, the frequency of events is going to be pretty high. Pekka -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/