Re: Why HZ on i386 is 100 ?

Alan Cox
2002-04-24T01:23:44Z

> I must not be making my self clear :) The overhead has nothing to do
> with hardware. It is all timer list insertion and deletion. The
> problem is that we need to do this at context switch rates, which are
> MUCH higher that tick rates and, even with the O(1) insertion code,
> cause the overhead to increase above the ticked overhead.

I remain unconvinced. Firstly the timer changes do not have to
occur at schedule rate unless your implementaiton is incredibly naiive.
Secondly for the specfic schedule case done that way, it would be even more
naiive to use the standard timer api over a single compare to getthe
timer list versus schedule clock.