> Stacks:
> 	KS - kernel stack - a per-user-thread stack in the kernel address space
> 	IS - interrupt stack - a single stack for handling all interrupts

some (many? most?) CPUs don't support seperate interrupt stacks...


> [Ref: alpha source code]

As Chris Torek noted, setup, etc., for ASTs should be deferred as long
as possible...

I sort of worry taht you're using the Alpha source code as a
reference, because it was "optimized for stability" rather than speed.
None of the Alpha code has been tweaked for speed, at all, yet.
(that should be somewhat obvious... note, for instance, that bcopy
does byte-at-a-time copies, and therefore is 8x less efficient than an
optimized version in some cases...  8-)


chris