[net.micro] CBM, Z8000, & Unix

schneids@ssc-vax.UUCP (Jim Schneidewind) (04/14/84)

  The following is from the April 9 issue of "Electronic Engineering

Times":

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   "Commodore International Ltd. released four new microcomputers.....

    The first new release is a Unix-based, 16-bit Z8000 computer system, with
256Kbytes of RAM, 80-column color graphics and built-in dual floppy-disk
drives.  The drives are surprises because initial indications were that the
company would produce an under-$800 single-drive machine."

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   I would guess that with 2 drives the price would be in the range of

$1000 to $1200.  Can't wait to get one!!

		Schneids
		ssc-vax!schneids

djc@sun.uucp (David J. Cardinal) (04/17/84)

UNIX's inability to run on floppy based systems seems to
be related to its need to always touch the disk, and
the lack of a disk cache in low end systems.

(The obvious problem is that the user can screw up the
disk and the cache by swapping floppies).

Data General's MPOS epitomizes a system that is "UNIX-like"
and combines the slowness with an inability to swap disks
without explicit commands (ported from a hard-disk system, typically).

On the other hand, the Quantum Software "QNX" system combines
infrequent and relatively rapid disk access with a rock-solid
file system (mostly due to simplicity).  I don't know the tricks
they have used, as I do not have source, but the result
is a definite step forward in UNIX-like floppy based systems.
(Note that QNX is not UNIX licensed, and is actually a pretty
nifty message-passing kernel emulating UNIX so that people will
buy it.)

Thus the problem seems not to be with UNIX per se, but with
implementations of operating systems developed on hard-disk
systems and then thoughtlessly ported to floppies.

--dave cardinal
	sun!djc
	

fair@dual.UUCP (Erik E. Fair) (04/22/84)

You may not want one once you check out its performance. I speak as one who
has used floppy based UNIX systems frequently enough to know that they are
S L O O O O O O O W W W W W W ! ! ! ! ! !

Ian Darwin, if you are reading this, you can make some more cogent comments,
and perhaps provide us with some colourful ancedotes.

	Erik E. Fair	ucbvax!fair	fair@ucb-arpa.ARPA

	dual!fair@Berkeley.ARPA
	{ihnp4,ucbvax,cbosgd,decwrl,amd70,fortune,zehntel}!dual!fair
	Dual Systems Corporation, Berkeley, California