From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750801AbVHQEQj (ORCPT ); Wed, 17 Aug 2005 00:16:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750809AbVHQEQj (ORCPT ); Wed, 17 Aug 2005 00:16:39 -0400 Received: from ms-smtp-04.nyroc.rr.com ([24.24.2.58]:27852 "EHLO ms-smtp-04.nyroc.rr.com") by vger.kernel.org with ESMTP id S1750801AbVHQEQi (ORCPT ); Wed, 17 Aug 2005 00:16:38 -0400 Subject: Re: [PATCH] [Fwd: Console locking and blanking] From: Steven Rostedt To: abonilla@linuxwireless.org Cc: Patrick Mochel , Benjamin Herrenschmidt , Linux Kernel list , Andrew Morton In-Reply-To: <1124250948.4855.93.camel@localhost.localdomain> References: <1124242875.8848.10.camel@gaston> <1124249381.8848.19.camel@gaston> <1124250271.5764.76.camel@localhost.localdomain> <1124250948.4855.93.camel@localhost.localdomain> Content-Type: text/plain Organization: Kihon Technologies Date: Wed, 17 Aug 2005 00:16:26 -0400 Message-Id: <1124252186.5764.82.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2005-08-16 at 21:55 -0600, Alejandro Bonilla Beeche wrote: > On Tue, 2005-08-16 at 23:44 -0400, Steven Rostedt wrote: > > On Wed, 2005-08-17 at 13:29 +1000, Benjamin Herrenschmidt wrote: > > > On Wed, 2005-08-17 at 11:41 +1000, Benjamin Herrenschmidt wrote: > > > > > > > (I'm blind and I use a braille display. I use those functions to blank > > > > my laptop's screen so people don't read it, and hopefully to conserve > > > > power.) > > > > At the OLS I learned that the backlight of a laptop (when the screen is > > black, but still glows) actually spends more wattage than when the > > screen is lit. So, unless you actually turn the laptop display off, > > switching it to black will actually burn the battery quicker. > > This sounds stupid. Who told you this? The actual brightness is the one > that consumes the most battery. > > Seriously, who told you such thing? > It was one of the speakers during the presentation. He seemed to know what he was talking about, in fact, I was caught so off guard by the statement, I got up and ask him the question again. "Did you say that the backlight of the laptop takes up more energy than when it is on?" and he replied "yes"! I rememeber this being in room C (could be wrong, I went to so many sessions). Looking at the program, it could have been "Linux Power Management" by Patrick Mochel. But I honestly don't remember which session it was. (I'm CCing him to see if he can clear things up :-) -- Steve