Re: 7.52 second kernel compile

[Linus Torvalds]

On Mon, 18 Mar 2002, Cort Dougan wrote:
>
> } But the whole point of _scattering_ is so incredibly broken in itself!
> } Don't do it.
>
> Yes, that is indeed correct theoretically.  The problem is that we actually
> measured it and there was very little locality.  When I added some
> multiple-tlb loads it actually decreased wall-clock performance for nearly
> every user load I put on the machine.

This is what I meant by hardware support for multiple loads - you mustn't
let speculative TLB loads displace real TLB entries, for example.

> Linus, I knew that deep in my heart 8 years ago when I started in on all
> this.  I'm with you but I'm not good enough with a soldering iron to fix
> every powerpc out there that forces that crappy IBM spawned madness upon
> us.

Oh, I agree, we can't fix existing broken hardware, we'll ave to just live
with it.

		Linus