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From: tagreen@bronze.ucs.indiana.edu (Todd A. Green)
Newsgroups: comp.sys.amiga.hardware
Subject: Re: Amiga Custom Chips - why hasn't C= made them faster?
Message-ID: <1991Apr5.152157.13339@bronze.ucs.indiana.edu>
Date: 5 Apr 91 15:21:57 GMT
References: <1991Apr3.201259.8377@engin.umich.edu> <1991Apr3.225433.16594@jato.jpl.nasa.gov> <1991Apr5.034303.14202@engin.umich.edu>
Organization: Indiana University, Bloomington
Lines: 47

In article <1991Apr5.034303.14202@engin.umich.edu> milamber@caen.engin.umich.edu (Daryl Scott Cantrell) writes:
>In article <1991Apr3.225433.16594@jato.jpl.nasa.gov> jdickson@jato.Jpl.Nasa.Gov (Jeff Dickson) writes:
>>In article <1991Apr3.201259.8377@engin.umich.edu> milamber@caen.engin.umich.edu (Daryl Scott Cantrell) writes:
>>>In article <1991Apr2.235710.13984@news.iastate.edu> xgr39@CCVAX.IASTATE.EDU writes:
>>>
>> 	
> [stuff about memory protection and resources deleted]
>
>3) There are a lot better things software people at CBM should worry about.
>Virtual memory comes to mind as a far more productive use for the MMU.  Can
>you say 100 MB free? [insert drool noise]  Not to mention color X-Windows
>for Unix, etc., etc... All of which (ok, some of which anyway..) I'm sure
>they're thinking-about/designing/coding/lying-to-us-about-not-having-yet at
>this very moment.

Can you say let's watch this window get paged in from disk? [insert
yawn noise here].  Have you ever used virtual memory on a system with
a relatively slow HD? Such as the Mac, NeXT, or MicroVaxII? (Not meant
as a flame, but just as a curiosity.) I'm assuming that you are being
a little bit on the facetious side when you say 100 mb free, so I
won't comment on that.

But, having VM on any pc, is not quite like having it on a mainframe
(like our RISC DEC 5840 with 4 CPU's running at 64 MIPS).  Besides the
advantage in pure processing power, these puppies have disk transfer
rates that would blow your mind.

Don't get me wrong VM is nice and has its purpose, but it is NOT a
substitute for RAM.  Case in point.  My workstation is a NeXT '030
cube that used to have 8mb of memory.  A day (actually more like a
minute :)) did not go by that I didn't have to wait on the machine as
my processes got swamped into and out of memory.  You seriously can
see your windows get read from disk. (It's kinda cool for about the
first 5 minutes).  I've since upgraded to 16mb of memory and the
performance increase is incredible. Like night and day...thought
someone had slipped an '040 board into the machine (until I actually
used a NeXT slab).

My point is that VM is nice, VM is good, VM is your friend, but it
ain't never gonna nohow replace RAM.

Todd
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