Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757738Ab0FFLLy (ORCPT ); Sun, 6 Jun 2010 07:11:54 -0400 Received: from mail-fx0-f46.google.com ([209.85.161.46]:33617 "EHLO mail-fx0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756886Ab0FFLLw (ORCPT ); Sun, 6 Jun 2010 07:11:52 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; b=B64AgAw9GIPWVnz8yzcm3BzOGnk6STxTqePc0zgZvsZFUMlLt/+AtdI0xN5ZjHq0nL zAl03HO6i/nYrNLT8KxieRCaQh3NPybQBvac1cjo/hCp86KBxhGxHgkgtlmigwUICHal c99KXvfQZAA0X2KnnhpUznJ+UrivKtz09EVio= MIME-Version: 1.0 In-Reply-To: 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> Date: Sun, 6 Jun 2010 14:11:50 +0300 Message-ID: Subject: Re: [linux-pm] suspend blockers & Android integration From: Felipe Contreras To: david@lang.hm Cc: Brian Swetland , Vitaly Wool , =?UTF-8?B?QXJ2ZSBIasO4bm5ldsOlZw==?= , Arjan van de Ven , tytso@mit.edu, Florian Mickler , Peter Zijlstra , "H. Peter Anvin" , LKML , Neil Brown , James Bottomley , Alan Cox , Linux PM , Ingo Molnar , Linux OMAP Mailing List , Linus Torvalds , Thomas Gleixner , Felipe Balbi Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1646 Lines: 33 2010/6/6 : > On Sun, 6 Jun 2010, Brian Swetland wrote: > if you could shrink the time awake to 0.01 second per wakeup you would shift > this all up a category (and avoiding the need to wake everything up to > service a timer would help do this) > > this effort very definantly has diminishing returns as you go to larger > sleep periods as the constant standby power draw becomes more and more > dominating. someone mentioned that they were getting the sleep time of > normal systems up past the 1 second mark with the 10 second mark looking > very attainable. that is where you get the most benifit for whatever changes > are needed. getting up to a 2 min sleep time really gives you about all the > benifit that you can get, going from there to 15 min makes very little > difference. > > don't let chasing the best possible sleep time prevent you from considering > options that would be good enough in time, but would drastically reduce the > maintinance effort (as things could be upstreamed more easily), and would be > usable on far more systems. Not to mention the fact that there's nothing fundamental that prevents dynamic PM to reach > 15 min idle. It's a matter of time before we find the tools needed. The amount of work that suspend blockers would require to implement properly in user-space other than Android just doesn't match the power savings. -- Felipe Contreras -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/