Re: [patch v2] epoll use a single inode ...

[H. Peter Anvin]

Linus Torvalds wrote:
> On Tue, 6 Mar 2007, Eric Dumazet wrote:
> > I did a user space program, attached to this mail.
> >
> > I rewrote the reciprocal_div() for i386 so that one multiply is used.
>
> Ok, this is definitely faster on Core 2 as well, so "numbers talk, 
> bullshit walks". No more objections.
>
> (That said, I bet you could do even better for octal and hex numbers, so 
> if you *really* want to speed things up, you should just make a 
> special-case routine for each base (there's just three of them), and you 
> can then also optimize the base-10 thing much better (you can do two 
> digits at a time by dividing by 100, etc)

Of course you can do better for octal and hex -- it's just shift and mask.

Decimal is trickier; however, at least on i386 it might make sense to 
divide by 100 and then use the AAM instruction, or a table lookup, to 
split it into individual digits.

	-hpa
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