Device polling performance

TM4525 at TM4525 at
Mon Sep 27 12:13:48 PDT 2004

In a message dated 9/27/04 3:04:22 PM Eastern Daylight Time, 
jerrymc at writes:
> Mike at previously wrote:
> "Given a decent CPU, you wont see very much of a load average at all in the 
> 200Kpps / 100Mb range."

Note that load average and CPU usage are two intirely different things.
You could have a huge amount of CPU usage with a load average hovering
around zero and somewhat vice versa too - eg high load average without
a great deal of CPU usage - though that would be less common.

Since device polling is entirely a kernel process (and userland "load 
average" has nothing to do with it), his statement would have been 
completely irrelevent if he were, in fact, talking about userland load 
average. Load average is virtually useless and shouldn't be part of any
conversation originating after 1990.

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