Re: BogoMIPS

Linus Torvalds (torvalds@transmeta.com)
Mon, 28 Sep 1998 18:11:16 -0700 (PDT)


On Mon, 28 Sep 1998, Richard B. Johnson wrote:
>
> Hmmm. It certainly helps here! It also has helped others who complained!

I did the same thing for 2.0.x a long time ago. It helped for certain
chips, but it still jittered for others. And it depended on how the kernel
got compiled - there was one (German?) person in particular who took the
bogomips loop into user code and tried it with tons of different
placements, and showed that for his CPU it made a difference how it was
placed and what the surrounding code was.

As a result, 2.0.x just does it as a separate subroutine in

arch/i386/lib/delay.S

and that pretty much forces it to not jitter at all. If you'd send me that
kind of patch I'd accept it.

Linus

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/