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Date:      Tue, 17 Oct 1995 11:37:43 -0700 (MST)
From:      Terry Lambert <terry@lambert.org>
To:        bde@zeta.org.au (Bruce Evans)
Cc:        hackers@FreeBSD.ORG, julian@ref.tfs.com
Subject:   Re: netisr code..
Message-ID:  <199510171837.LAA28008@phaeton.artisoft.com>
In-Reply-To: <199510170755.RAA00245@godzilla.zeta.org.au> from "Bruce Evans" at Oct 17, 95 05:55:47 pm

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> That is slower at the end.  However, micro-optimizations here are probably
> not important.  Everything except the atomic btrl could be written in C
> and you probably wouldn't notice the difference.

I would.  ;-).

I guess I'm just a computational nanosecond kinda guy.  Comes from
growing up on 1KHz machines with 8k or less of memory, I suppose,
instead of on VAXen "where instructions are emulated and memory is
free".

The attitute that an optimization "doesn't matter" (this one is a bad
example -- it's not really an optimization) is bad.

That said, there is plenty of "low hanging fruit" that should be picked
before going into instruction counting mode (unless you are doing kernel
function block profiling -- if you are, then you have arrows pointing to
where you need to fix the code).


Now to totally confuse things: I think there should be C versions of
all possible assembly code to aid porting.  Anything that works is
better than anything that doesn't.


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.



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