From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Garrett Subject: Re: [PATCH 0/8] Suspend block api (version 6) Date: Mon, 17 May 2010 20:34:40 +0100 Message-ID: <20100517193440.GA32066@srcf.ucam.org> References: <1272667021-21312-1-git-send-email-arve@android.com> <87wrvl5479.fsf@deeprootsystems.com> <20100503215028.GB18910@srcf.ucam.org> <20100514203202.GA12409@srcf.ucam.org> <87aas2azc5.fsf@deeprootsystems.com> <20100514231510.GG16989@thunk.org> <87r5laa4oc.fsf@deeprootsystems.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: Vitaly Wool Cc: Greg Kroah-Hartman , Jesse Barnes , linux-kernel@vger.kernel.org, linux-pm@lists.linux-foundation.org, Liam Girdwood , Len Brown , Jacob Pan , Oleg Nesterov , linux-omap@vger.kernel.org, Linus Walleij , Daniel Walker , tytso@mit.edu, Brian Swetland , Mark Brown , Geoff Smith , Tejun Heo , Andrew Morton , Wu Fengguang , Arjan van de Ven List-Id: linux-omap@vger.kernel.org On Mon, May 17, 2010 at 09:27:47PM +0200, Vitaly Wool wrote: > Exactly. The point is, opportunistic suspend doesn't in fact add any > value compared to dynamic PM + CPUIdle. It only produces some false > impression that one can handle power management right without using > dynamic PM. And this false impression is the cause for many really > ugly designs (like, for instance, 15 minutes touchscreen inactivity > delay before forcibly shutting down the wireless, as it's done in > stock Android framework). Run this (or equivalent code) on an N900 and on an Android. Measure the screen-off power draw on both. int main() { int i; while (1) i++; return 0; } -- Matthew Garrett | mjg59@srcf.ucam.org