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Re: [PATCH 0/8] Suspend block api (version 6)

From:  Matthew Garrett <mjg-AT-redhat.com>
To:  Kevin Hilman <khilman-AT-deeprootsystems.com>
Subject:  Re: [PATCH 0/8] Suspend block api (version 6)
Date:  Mon, 17 May 2010 22:34:37 +0100
Cc:  Greg Kroah-Hartman <gregkh-AT-suse.de>, Jesse Barnes <jbarnes-AT-virtuousgeek.org>, Oleg Nesterov <oleg-AT-redhat.com>, linux-pm-AT-lists.linux-foundation.org, Liam Girdwood <lrg-AT-slimlogic.co.uk>, Len Brown <len.brown-AT-intel.com>, Jacob Pan <jacob.jun.pan-AT-linux.intel.com>, linux-omap-AT-vger.kernel.org, Linus Walleij <linus.walleij-AT-stericsson.com>, Daniel Walker <dwalker-AT-codeaurora.org>, tytso-AT-mit.edu, Geoff Smith <geoffx.smith-AT-intel.com>, Brian Swetland <swetland-AT-google.com>, Mark Brown <broonie-AT-opensource.wolfsonmicro.com>, linux-kernel-AT-vger.kernel.org, Tejun Heo <tj-AT-kernel.org>, Andrew Morton <akpm-AT-linux-foundation.org>, Wu Fengguang <fengguang.wu-AT-intel.com>, Arjan van de Ven <arjan-AT-infradead.org>
Archive-link:  Article, Thread

On Mon, May 17, 2010 at 02:27:52PM -0700, Kevin Hilman wrote:
> Matthew Garrett <mjg@redhat.com> writes:
> > 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;
> > }
> 
> This kind of rogue app will also kill my CPU performance.  For rogue
> CPU-hog apps, we use _tools_ to find and fix this kind of problem:
> top, renice, kill, etc. that use features of the scheduler to find
> and/or solve the problem.

If my phone is able to avoid losing almost all of its standby time 
without me having to care about whether my bouncing cow game was written 
by a complete fool or not, that means that my phone is *better* than one 
where I have to care. Would the world be better if said fool could be 
sent to reeducation camps before being allowed to write any more 
software? Probably, but sadly that doesn't seem to be something we can 
implement through code. I'd love it if we could assume that all software 
is going to be perfect, but in the absence of that ideal world there's a 
strong incentive to develop technology that does its best to cope with 
adverse situations.

-- 
Matthew Garrett | mjg59@srcf.ucam.org


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