From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756965Ab0EZR2f (ORCPT ); Wed, 26 May 2010 13:28:35 -0400 Received: from ksp.mff.cuni.cz ([195.113.26.206]:56760 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755540Ab0EZR2c (ORCPT ); Wed, 26 May 2010 13:28:32 -0400 Date: Wed, 26 May 2010 19:28:24 +0200 From: Pavel Machek To: James Bottomley Cc: Peter Zijlstra , Pekka Enberg , Arve Hj?nnev?g , Florian Mickler , "Rafael J. Wysocki" , Alan Stern , Dmitry Torokhov , Linux-pm mailing list , Kernel development list , Len Brown , Randy Dunlap , Andrew Morton , Andi Kleen , Cornelia Huck , Tejun Heo , Jesse Barnes , Nigel Cunningham , Ming Lei , Wu Fengguang , Maxim Levitsky , linux-doc@vger.kernel.org, Matthew Garrett , Greg KH , tytso@mit.edu Subject: Re: [PATCH 1/8] PM: Opportunistic suspend support. Message-ID: <20100526172824.GA9069@elf.ucw.cz> References: <1274868384.5882.5169.camel@twins> <1274869262.5882.5222.camel@twins> <1274890736.4467.574.camel@mulgrave.site> <1274891308.1674.1766.camel@laptop> <1274892847.4467.674.camel@mulgrave.site> <1274893228.1674.1772.camel@laptop> <1274894042.4467.727.camel@mulgrave.site> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1274894042.4467.727.camel@mulgrave.site> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed 2010-05-26 12:14:02, James Bottomley wrote: > On Wed, 2010-05-26 at 19:00 +0200, Peter Zijlstra wrote: > > On Wed, 2010-05-26 at 11:54 -0500, James Bottomley wrote: > > > Given that I'm in the latter category, I think suspend blockers is a > > > reasonable solution to an existing problem. I like Alan's idea of > > > restricting the API into a single user space program so we contain the > > > API contamination ... but realistically that's mostly the current > > > suspend blockers anyway. > > > > There's a _large_ difference between resource limits and these wonky > > suspend blockers. > > Well, you have policy and then you have implementation ... suspend > blockers just looks like an implementation to me. It seems to be > reasonably well suited in that regard ... after all, we kill processes > that exhaust memory for instance or cut off write privileges to those > that go over quota. Preventing power hungry processes from consuming > power by not allowing them to run until there's a wakeup event is fairly > gentle by those standards. Well, generic mechanism would stop processes when they run over something -- not arbitrarily link it to device wakeup. > > The main and most important one being that suspend is a global property > > and can/will hurt sensible tasks. It puts the whole task model upside > > down. > > OK, so I believe you have an android phone ... it already implements > this model ... specifically what are the problems on that platform this > causes? Besides that it is not linux system at all? Yes, with custom userspace it works extremely nicely. Had anyone even tried running oportunistic suspend on normal desktop? Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html