Re: Serial port latency

Manfred Spraul (manfred@colorfullife.com)
Thu, 22 Mar 2001 22:45:58 +0100


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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