From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932135AbWFMPYE (ORCPT ); Tue, 13 Jun 2006 11:24:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932138AbWFMPYE (ORCPT ); Tue, 13 Jun 2006 11:24:04 -0400 Received: from omx1-ext.sgi.com ([192.48.179.11]:48036 "EHLO omx1.americas.sgi.com") by vger.kernel.org with ESMTP id S932137AbWFMPYD (ORCPT ); Tue, 13 Jun 2006 11:24:03 -0400 Date: Tue, 13 Jun 2006 08:23:51 -0700 (PDT) From: Christoph Lameter To: Martin Peschke cc: linux-kernel@vger.kernel.org, ak@suse.de, akpm@osdl.org, alan@lxorguk.ukuu.org.uk Subject: Re: [RFC] Light weight event counters (V2) instead of page state In-Reply-To: <448EC436.6060008@de.ibm.com> Message-ID: References: <448EC436.6060008@de.ibm.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 13 Jun 2006, Martin Peschke wrote: > Did you consider using the statistics infrastructure available in -mm? > (lib/statistic.c, include/linux/statistic.h, Documentation/statistics.txt) No its not in Linus tree and has even more overhead than the existing counters since it always checks if a certain counters is on or off and it also does indirect calls to an update function. It does not use local_t at all and takes an smp_processor_id() parameter to various functions which makes the future use of cpu_local_* functions not possible (should that implementation get fixed). > To me that looks like a good application for the statistics infrastructure, > which shows statistics through debugfs instead of procfs. Btw., it completely > unburdens exploiting kernel code from the delivery of statistics to users. The light weight counter implementation here provides the output of /proc/vmstat. That is a fixed interface.