Re: No 100 HZ timer !

John Alvord
2001-08-02T17:26:11Z

On Thu, 02 Aug 2001 09:36:07 -0700, george anzinger
<george@mvista.com> wrote:
...
> The timing
>tests (800MHZ PIII) show the whole setup taking an average of about 1.16
>micro seconds. the problem is that this happens, under kernel compile,
>~300 times per second, so the numbers add up. Note that the ticked
>system timer overhead (interrupts, time keeping, timers, the works) is
>about 0.12% of the available cpu. Under heavy load this raises to about
>0.24% according to my measurments. The tick less system overhead under
>the same kernel compile load is about 0.12%. No load is about 0.012%,
>but heavy load can take it to 12% or more, most of this comming from the
>accounting overhead in schedule(). Is it worth it?

I thought the claimed advantage was on certain S/390 configurations
(running 100s of Linux/390 images under VM) where the cost is
multiplied by the number of images. A measurement on another platform
may be interesting but not conclusive.

john alvord