Re: [PATCH][2.6] Completely out of line spinlocks / x86_64

[Zwane Mwaikambo]

On Mon, 9 Aug 2004, Andi Kleen wrote:

> I think the 50k number is wrong. I took a look at it and the big
> difference is only seen when you enable interrupts during spinning, which
> we didn't do before.  If you compare it to the old implementation the
> difference is much less.

Yes agreed the increase wouldn't be of as high a magnitude if compared to
the original code, but it's still a decent saving.

> I don't really like the config option. Either it's a good idea
> then it should be done by default without option or it should not be done at all.
>
> Did you do any lock intensive benchmarks that could show a slowdown?

I went for a file IO type benchmark, the differences looked like
statistical noise, possibly the best bet would be to check for cache
hits/misses.

> You should make this file assembly only.

Ok you're the second person to mention that, i don't have a problem with
switching to assembly only and dumping the exports in x8664_ksyms.c

Thanks,
	Zwane

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