From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brian Swetland Subject: Re: suspend blockers & Android integration Date: Sat, 5 Jun 2010 15:26:36 -0700 Message-ID: References: <20100603193045.GA7188@elte.hu> <20100603231153.GA11302@elte.hu> <20100603232302.GA16184@elte.hu> <20100604071354.GA14451@elte.hu> <20100604083423.GD15181@elte.hu> <1275653210.27810.39762.camel@twins> <1275731653.27810.41078.camel@twins> <20100605092851.6ee15f13@infradead.org> <20100605152326.7ccd5160@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: <20100605152326.7ccd5160@infradead.org> Sender: linux-kernel-owner@vger.kernel.org To: Arjan van de Ven Cc: =?UTF-8?B?QXJ2ZSBIasO4bm5ldsOlZw==?= , Peter Zijlstra , Ingo Molnar , tytso@mit.edu, Neil Brown , Thomas Gleixner , "Rafael J. Wysocki" , Alan Stern , Felipe Balbi , LKML , Florian Mickler , Linux OMAP Mailing List , Linux PM , Alan Cox , James Bottomley , Linus Torvalds , Kevin Hilman , "H. Peter Anvin" List-Id: linux-omap@vger.kernel.org On Sat, Jun 5, 2010 at 3:23 PM, Arjan van de Ven wrote: >> >> We clearly have different standards for what we consider good. We >> measure time suspended in minutes or hours, not seconds, and waking up >> every second or two causes a noticeable decrease in battery life on >> the hardware we have today. > > I guess I'm spoiled working with (unreleased) hardware that knows how > to power gate ;-) I'm continually surprised by answers like this. We run on hardware that power gates very aggressively and draws in the neighborhood of 1-2mA at the battery when in the lowest state (3-5mA while the radio is connected to the network and paging). Waking up out of that lowest state and executing code every few seconds or (worse) several times a second) will raise your average power consumption. Being able to stay parked at the very bottom for minutes or hours at a time when nothing "interesting" is happening is very useful and can have a significant impact on overall battery life. Brian