From: utzoo!decvax!ucbvax!info-cpm
Newsgroups: fa.info-cpm
Title: MARC
Article-I.D.: ucbvax.237
Posted: Sun Dec  5 23:50:38 1982
Received: Mon Dec  6 09:01:24 1982

>From vortex!lauren@Lbl-Unix  Sun Dec  5 23:47:19 1982
To: RMS.G.BANDY.MIT-OZ@Mit-Ml
Cc: INFO-CPM@BRL
Via:  Lbl-Unix; 5 Dec 82 22:56-EST
Via:  Brl; 5 Dec 82 23:17-EST
Via:  Brl-Bmd; 5 Dec 82 23:26-EST

I'm glad you've seen MARC, but please don't spread misinformation
around!  MARC does NOT require "BIG in-memory buffers".  All existing
MARC implementations run within 64K bytes.  I have run MARC successfully
in as little as 48K, but admittedly that was a bit cramped for getting
anything useful done.  You DON'T need a "big winnie" either.  Hard
disks are nice on almost any system, but MARC will run fine even on
single-density 8 inch floppies.  Since there are so many utilities
(resulting in a pretty large /bin) it's nice to have double-density
floppies so that you can fit all the utilities onto your root disk, but
even running single-density it is fairly trivial to simply put most
of your "infrequently used" programs on a different filesystem (floppy).

I've never been able to figure out exactly how to benchmark MARC, but
on my single-density system, the access times generally seem to be
at least as good as I get for CP/M, overall.  Certain tasks might
take a bit longer and some a bit shorter, but overall the feeling
is that they are very similar.  Note that MARC does NOT handle disk
accessing (internally) exactly the same way as UNIX, and there have
been conscious design decisions made with an eye toward good performance
on smaller disks (for example, file block buffering is handled differently,
and the shell search path is essentially reversed from that of standard
Unix).

Most of the test sites ran double-density systems with 58-64K bytes,
and they generally reported that performance was very good, even 
with their simple floppy systems.  Obviously the quality of your
BIOS, and similiar factors, will impact overall performance, and a
hierarchical filesystem implies more time spent performing certain
tasks (and less time performing others), but overall the reaction
has been very good.

--Lauren--