linux-kernel - RE: msleep() an load average

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Message-ID: <48D3D52125C49B43AE880038E2E5314BB5BE9F@SRV101.gdsys.de>
Date:	Wed, 4 May 2011 16:04:06 +0200
From:	"Eibach, Dirk" <Eibach@...ys.de>
To:	"Clemens Ladisch" <clemens@...isch.de>
Cc:	<linux-kernel@...r.kernel.org>
Subject: RE: msleep() an load average

> > while(1) msleep_interruptible(1000);
> > 
> > Is this code really any better?
> 
> You should handle signals, probably by blocking any that 
> you're not interested in, and exiting on any fatal one.

As I am a great kernel hacker, all signals are blocked ;)

> Anyway, polling is bad; this code forces the CPU to wake up 
> once per second.  What is your thread _actually_ waiting for?
> (I guess it has more code than what you wrote?)

Sure, polling is bad, but sometimes hard to avoid. My system is
monitoring some hardware it doesn't trust and looks once in a while if
it's still alive, just to make sure. As this is an embedded system
without any energy saving measures, waking up the CPU is not that much
of a problem.

Cheers
Dirk
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