From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964798AbWFNMsU (ORCPT ); Wed, 14 Jun 2006 08:48:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964899AbWFNMsU (ORCPT ); Wed, 14 Jun 2006 08:48:20 -0400 Received: from dtp.xs4all.nl ([80.126.206.180]:35645 "HELO abra2.bitwizard.nl") by vger.kernel.org with SMTP id S964900AbWFNMsT (ORCPT ); Wed, 14 Jun 2006 08:48:19 -0400 Date: Wed, 14 Jun 2006 14:48:17 +0200 From: Erik Mouw To: sena seneviratne Cc: linux-Kernel@vger.kernel.org Subject: Re: Introduce a New Metrics to measure Load average. Message-ID: <20060614124816.GD11542@harddisk-recovery.com> References: <5.1.1.5.2.20060614150410.0465ceb0@brain.sedal.usyd.edu.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5.1.1.5.2.20060614150410.0465ceb0@brain.sedal.usyd.edu.au> Organization: Harddisk-recovery.com User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 14, 2006 at 03:12:29PM +1000, sena seneviratne wrote: > The problem with the load metric of current Linux/Unix is that it measures > CPU load and Disk load without indicating the true nature of the load, > thereby creating some confusion among the readers. For example, if a CPU > bound task switches on to read a large chunk of disk data, then the load > average value would still continue to indicate this activity as a load, yet > the true CPU load during this period would have been zero. Right, we've seen such things with busy servers. > This situation > triggered us to make necessary additions to the kernel so that CPU load and > Disk load could be reported separately. Further the specialisation of load > helped our model to perform predictions when there is interference between > CPU and Disk IO loads. OK. > In the user mode, a new proc file called /proc/loadavgus would collect the > new data according to a new format which would look like the following, > > CPU Disk > Root 0.7 0 > User1 0.9 1 > User2 0.9 0 > User3 1.03 1 > User4 0.93 0 > User5 1.0 0 The kernel doesn't know about user names, only uids. So the layout should be something like: CPU Disk 0 0.7 0 500 0.9 1 501 0.9 0 > What do you think about this change? Why do you want to tell the load per user? Just the CPU and disk load should be sufficient. Erik -- +-- Erik Mouw -- www.harddisk-recovery.com -- +31 70 370 12 90 -- | Lab address: Delftechpark 26, 2628 XH, Delft, The Netherlands