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Date: Tue, 06 Dec 2005 14:18:18 +0100
From: Fredrik Lindberg <fli+freebsd-current@shapeshifter.se>
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Cc: Travis Mikalson <bofh@terranova.net>, current@freebsd.org, njl@freebsd.org
Subject: Re: powerd
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Dag-Erling Smørgrav wrote:
> Fredrik Lindberg <fli+freebsd-current@shapeshifter.se> writes:
> 
>>Dag-Erling Smørgrav wrote:
>>
>>>If the devd loop is an *alternative* to the polling loop, there's
>>>even less reason to use threads.
>>
>>Yes it's an alternative, reading a variable versus doing a sysctl call
>>each interation. It seemed like I good idea, when I first wrote this
>>(almost a year ago), to have a thread providing a cached value of the
>>AC state. But maybe I was trying to be too smart or something.
> 
> 
> Yes.  Not only is it a bad design idea, but the implementation is
> wrong, and likely to fail badly when compiled at high optimization
> levels.

Ignoring the fact that it does work with -O3 (gcc 3.4.4), could you
please explain why it has the potential of failing with high
optimizations.

Fredrik Lindberg