From owner-freebsd-arch@FreeBSD.ORG Sat Mar 22 02:54:08 2008 Return-Path: Delivered-To: arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 00D87106566C for ; Sat, 22 Mar 2008 02:54:08 +0000 (UTC) (envelope-from gnn@neville-neil.com) Received: from proxy.meer.net (proxy.meer.net [64.13.141.13]) by mx1.freebsd.org (Postfix) with ESMTP id CD6AD8FC16 for ; Sat, 22 Mar 2008 02:54:07 +0000 (UTC) (envelope-from gnn@neville-neil.com) Received: from outbound0.mx.meer.net (outbound0.mx.meer.net [209.157.153.23]) by proxy.meer.net (8.14.2/8.14.2) with ESMTP id m2M0P2nL072803; Fri, 21 Mar 2008 17:25:02 -0700 (PDT) (envelope-from gnn@neville-neil.com) Received: from mail.meer.net (mail.meer.net [209.157.152.14]) by outbound0.mx.meer.net (8.12.10/8.12.6) with ESMTP id m2M0AGi9078374; Fri, 21 Mar 2008 16:10:22 -0800 (PST) (envelope-from gnn@neville-neil.com) Received: from mail2.meer.net (mail2.meer.net [64.13.141.16]) by mail.meer.net (8.13.3/8.13.3/meer) with ESMTP id m2M09cQg077660; Fri, 21 Mar 2008 17:09:38 -0700 (PDT) (envelope-from gnn@neville-neil.com) Received: from minion.local.neville-neil.com (61.204.211.246.customerlink.pwd.ne.jp [61.204.211.246]) (authenticated bits=0) by mail2.meer.net (8.14.1/8.14.1) with ESMTP id m2M09bhl037110; Fri, 21 Mar 2008 17:09:38 -0700 (PDT) (envelope-from gnn@neville-neil.com) Date: Sat, 22 Mar 2008 09:09:37 +0900 Message-ID: From: gnn@freebsd.org To: Robert Watson In-Reply-To: <20080318182358.F34016@fledge.watson.org> References: <5753.1205785282@critter.freebsd.dk> <20080318182358.F34016@fledge.watson.org> User-Agent: Wanderlust/2.15.5 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.8 (=?ISO-8859-4?Q?Shij=F2?=) APEL/10.7 Emacs/22.1.50 (i386-apple-darwin8.10.1) MULE/5.0 (SAKAKI) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII X-Bayes-Prob: 0.5 (Score 0) X-Spam-Score: 0.70 () [Tag at 5.00] COMBINED_FROM,NO_REAL_NAME X-CanItPRO-Stream: default X-Canit-Stats-ID: 60370 - 853375b3dfd4 X-Scanned-By: CanIt (www . roaringpenguin . com) on 64.13.141.13 Cc: arch@freebsd.org, Poul-Henning Kamp Subject: Re: Power-Mgt (Was: Re: cvs commit: src/sys/i386/cpufreq est.c ) X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 22 Mar 2008 02:54:08 -0000 At Tue, 18 Mar 2008 18:26:11 +0000 (GMT), rwatson wrote: > > > I know we've talked about this, but I'll mention it for the benefits > of the mailing list: one of the things that makes performance an > "easy" target is that there are easy-to-gather metrics. Those > metrics may require knowledge of statistics and a lifetime of > experience to interpret correctly, but they are still numbers that > are easily generated and compared. To drive work in power > management, we would benefit from having similarly accessible > metrics. Are there any decent documents describing how to do power > use measurement, and are there any (relatively) accessible tools for > doing it with? For example, on notebooks, can we sample an ACPI > value before/after a benchmark, or do we really need to hook > something up to the power supply in order to get a useful number? > Queue did a series on this a while back, some decent articles and ideas in there: http://www.acmqueue.org/modules.php?name=Content&pa=list_pages_issues&issue_id=46 http://www.acmqueue.org/modules.php?name=Content&pa=showpage&pid=513 Later, George