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Date: Thu, 17 Jan 2008 16:16:23 -0600
From: Scott Wood <scottwood@freescale.com>
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To: Matias Sundman <linux@sundmangroup.com>
Subject: Re: SCHED_FIFO & System()
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Matias Sundman wrote:
> Hello,
> I have some strange behavior in one of my systems.
> 
> I have a real-time thread under SCHED_FIFO which is running every 10ms. 
> It is blocking on a semaphore and released by a timer interrupt every 10ms.
> Generally this works really well.
> 
> However, there is a module in the system that makes a / system() / call 
> from c-code ;
> 
>   system("run_my_script");
> 
> By calling and running a bash script. Independent of how the actual 
> script looks like the real time thread does not get scheduled under 80ms 
> -- the time it takes
> for the system() call to finish.

Are you running a preemptible kernel?

-Scott