Re: RFC: issues concerning the next NAPI interface

On Fri, Aug 24, 2007 at 11:11:56PM +0200, Jan-Bernd Themann wrote:

(when they are available for
POWER in our case). 

hrtimer worked fine on the powerpc cell arch last summer.
I assume they work on p5 and p6 too, no ??

I tried to implement something with "normal" timers, but the result
was everything but great. The timers seem to be far too slow.
I'm not sure if it helps to increase it from 1000HZ to 2500HZ
or more.

Heh. Do the math. Even on 1gigabit cards, that's not enough:

(1gigabit/sec) x (byte/8 bits) x (packet/1500bytes) x (sec/1000 jiffy) 

is 83 packets a jiffy (for big packets, even more for small packets, 
and more again for 10 gigabit cards). So polling once per jiffy is a 
latency disaster.

--linas