Subject: Re: Thanks! (RE: Installing NetBSD 1.5 on Mac68k)
To: <>
From: Emile Schwarz <emile.schwarz@wanadoo.fr>
List: port-mac68k
Date: 12/16/2000 08:05:34
On Fri, 15 Dec 2000, Pat Wendorf wrote:
> - The SCSI performance seems a little slow. I know this is a fairly old
> machine, but I have a few x86 boxes of similar CPU speed (33mhz), and
> the IDE on my 486's seems significantly faster in NetBSD. Not that I'm
> complaining, I'm just wondering if it's the drive or the architecture.
> Once something is loaded into memory, it seems to run reasonably fast.
Paul Goyette <paul@whooppee.com> Answers:
>Architectural limitation. Mac's don't have DMA, so we have to simulate
>it. It is _very_ slow.
Not fully true.
The right answer is:
Only some Macintosh have DMA implentemented, so we have...
Example of Apple Computer that implement DMA:
Macintosh IIfx (yes old);
Apple II with Apple SCSI High Speed Card (same age) *.
Emile
* I have a SCSI demo disk that let people see a part of Star Wars (yes, a piece
of the movie) using full Apple IIGS Screen (geyscale) with a perfect image run
flow: around 30 seconds taken from the chase in the meteorite field. This was
done back in 1990 (I think).