Re: [announce] [patch] ultra-scalable O(1) SMP and UP scheduler

From: Linus Torvalds (torvalds@transmeta.com)
Date: Sun Jan 06 2002 - 22:34:36 EST


On Sun, 6 Jan 2002, Davide Libenzi wrote:
>
> 32 bit words lookup can be easily done in few clock cycles in most cpus
> by using tuned assembly code.

I tried to time "bsfl", it showed up as one cycle more than "nothing" on
my PII.

It used to be something like 7+n cycles on a i386, if I remember
correctly. It's just not an issue any more - trying to use clever code to
avoid it is just silly.

                Linus

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