>Andreas posted a release of his lil package on Aug 27. He notes that linux
>shows periodic high interrupt latency due to large amount of time
>(~15us) spent in the bottom handler processing in IRQ0.
Nonono. It' s not the time spent in the bottom_half. It' s the time spent
in the timer interrupt code that runs cli()ed. The first __sti() is in
do_bottom_half() a bit _before_ start running the bottom half handlers.
>I shall ofcourse do a lil more math to satisfy myself.. if anyone is
>interested .. I can keep you posted.
I am interested of course ;-). Using floating point to calc the mean is
pretty trivial.
There was a suggestion also to hack the timer irq to get:
irq0-time1 = x1 cycles
irq0-time2 = x2 cycles
irq0-time3 = x3 cycles
and then do the math over the xN cycles.
Andrea[s] Arcangeli
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