From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755414Ab0JLAVV (ORCPT ); Mon, 11 Oct 2010 20:21:21 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:47188 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755074Ab0JLAVU (ORCPT ); Mon, 11 Oct 2010 20:21:20 -0400 Date: Mon, 11 Oct 2010 17:22:26 -0700 From: Andrew Morton To: KAMEZAWA Hiroyuki Cc: Jack Steiner , yinghai@kernel.org, mingo@elte.hu, linux-kernel@vger.kernel.org Subject: Re: Problem: scaling of /proc/stat on large systems Message-Id: <20101011172226.6162476c.akpm@linux-foundation.org> In-Reply-To: <20101012090907.5dd1cf57.kamezawa.hiroyu@jp.fujitsu.com> References: <20100929122206.GA30317@sgi.com> <20100930140901.037f9dc7.kamezawa.hiroyu@jp.fujitsu.com> <20101004143414.GA4261@sgi.com> <20101005103650.7ebe64f0.kamezawa.hiroyu@jp.fujitsu.com> <20101005171907.23c75102.kamezawa.hiroyu@jp.fujitsu.com> <20101008163557.GA13859@sgi.com> <20101012090907.5dd1cf57.kamezawa.hiroyu@jp.fujitsu.com> X-Mailer: Sylpheed 2.7.1 (GTK+ 2.18.9; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 12 Oct 2010 09:09:07 +0900 KAMEZAWA Hiroyuki wrote: > > > > > > How about this ? This is an add-on patch. > > > > Nice!! > > > > The combination of the 2 patches solves the problem. > > The timings are (4096p, 256 nodes, 4592 irqs): > > > > # time cat /proc/stat > /dev/null > > > > Baseline: 12.627 sec > > Patch1 : 2.459 sec > > Patch 1 + Patch 2: .561 sec > > > > > > Acked-by: Jack Steiner > > > > Thank you for testing. I'll post again if necessary. Yes please. This has been going on for two weeks so memories need refreshing. Also we have no patch title and no changelog which includes the testing results. I could stitch all that together of course, but it's best that it all be done afresh, I think.