Device polling performance

TM4525 at TM4525 at
Sat Sep 25 06:57:27 PDT 2004

In a message dated 9/24/04 11:28:36 PM Eastern Daylight Time, mike at 
>I thought I'd reword my question since no one seemed to understand the first 
>Is there a way to measure CPU kernel/interrupt usage when device polling is 
>enabled on 4.x systems? top and systat both show 100% idle all of the time.

    As long as all your interfaces support polling, you should see
hardly see any interrupt usage at all, as that is the whole point of
polling.  You can allocate more or less CPU cycles to flinging packets
around via various sysctl settings.  See the polling man pages for
more info

Thanks, but that doesn't answer the question. Since polling cycles don't seem 
to be shown under any usage category, how do you know what your system usage 
is when polling is enabled? It seems like a big negative to me.


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