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Subject: Re: [PATCH 0/8] Suspend block api (version 6)
From: =?ISO-8859-1?Q?Arve_Hj=F8nnev=E5g?= <arve@android.com>
To: Pavel Machek <pavel@ucw.cz>
Cc: Matthew Garrett <mjg@redhat.com>,
       Kevin Hilman <khilman@deeprootsystems.com>,
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On Mon, May 24, 2010 at 11:57 AM, Pavel Machek <pavel@ucw.cz> wrote:
> Hi!
>
>> I agree that the runtime scenario is a far more appealing one from an
>> aesthetic standpoint, but so far we don't have a very compelling
>> argument for dealing with the starting and stopping of userspace. The
>> use-cases that Google have provided are valid and they have an
>> implementation that addresses them, and while we're unable to provide an
>> alternative that provides the same level of functionality I think we're
>> in a poor position to prevent this from going in.
>
> Uhuh?
>
> "We have this ugly code here, but it works and we don't have better
> one, so lets merge it"?
>
> I don't really like this line of reasoning. I would not want to judge
> wakelocks here, but... "it works, merge it" should not be used as
> argument.
>
> And btw I do have wakelock-less implementation of autosleep, that only
> sleeped the machine when nothing was ready to run. It was called
> "sleepy linux". Should I dig it out?
>
> Major difference was that it only sleeped the machine when it was
> absolutely certain machine is idle and no timers are close to firing
> -- needing elimination or at least markup of all short timers. It
> erred on side of not sleeping the machine when it would break
> something.
>

How did you handle external events that occur right after you decided to sleep?

> Still I believe it is better design than wakelocks -- that need
> markup/fixes to all places where machine must not sleep -- effectively
> sleeping the machine too often than fixing stuff with wakelocks all
> over kernel and userspace...

-- 
Arve Hjønnevåg