Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1424613AbWKQAFP (ORCPT ); Thu, 16 Nov 2006 19:05:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1424614AbWKQAFO (ORCPT ); Thu, 16 Nov 2006 19:05:14 -0500 Received: from mail.kroah.org ([69.55.234.183]:4251 "EHLO perch.kroah.org") by vger.kernel.org with ESMTP id S1424613AbWKQAFN (ORCPT ); Thu, 16 Nov 2006 19:05:13 -0500 Date: Thu, 16 Nov 2006 12:01:12 -0800 From: Greg KH To: Edward Falk Cc: linux-kernel@vger.kernel.org, jens.axboe@oracle.com, Andrew Morton Subject: Re: [PATCH] Introduce block I/O performance histograms Message-ID: <20061116200112.GA27089@kroah.com> References: <455BD7E8.9020303@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <455BD7E8.9020303@google.com> User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1293 Lines: 30 On Wed, Nov 15, 2006 at 07:15:52PM -0800, Edward Falk wrote: > This patch introduces performance histogram record keeping for block > I/O, used for performance tuning. It is turned off by default. > > When turned on, you simply do something like: > > # cat /sys/block/sda/read_request_histo > rows = bytes columns = ms > 10 20 50 100 200 500 1000 2000 > 2048 5 0 0 0 0 0 0 0 > 4096 0 0 0 0 0 0 0 0 > 8192 17231 135 41 10 0 0 0 0 > 16384 4400 24 6 2 0 0 0 0 > 32768 2897 34 4 4 0 0 0 0 > 65536 7089 87 5 1 2 0 0 0 Eeek, no, sysfs is for ONE VALUE PER FILE please. Yes, I know there are some other sysfs files that do not follow this rule, and we are working on fixing some of them, but please, don't add new ones that do violate this rule. thanks, greg k-h - 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/