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From: "Manfred Spraul" <manfred@colorfullife.com>
To: <geirt@powertech.no>
Cc: <linux-kernel@vger.kernel.org>
Subject: Re: Serial port latency
Date: Thu, 22 Mar 2001 22:45:58 +0100
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Is the computer otherwise idle?
I've seen one unexplainable report with atm problems that disappeared
(!) if a kernel compile was running.

Could you try to run a simple cpu hog (with nice 20)?

<<
main()
{
    for(;;) getpid();
}
<<

I'm aware of one bug that could cause a delay of up to 20 ms (cpu_idle()
doesn't check for pending softirq's before sleeping), but that doesn't
explain your 500 ms delay.

--
    Manfred

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