Re: Why HZ on i386 is 100 ?

Alan Cox
2002-04-23T06:50:53Z

> The problem is in accounting (or time slicing if you prefer) where we
> need to start a timer each time a task is context switched to, and stop
> it when the task is switched away. The overhead is purely in the set up
> and tear down. MOST of these never expire.

Done properly on many platforms a variable tick is very very easy and also
very efficient to handle. X86 is a paticular problem case because the timer
is so expensive to fiddle with