Newsgroups: comp.sys.amiga.advocacy
Subject: Re: Amiga 4000/Atari Falcon
From: fheitkamp@desire.wright.edu
Date: 31 Aug 92 06:41:54 EST
Organization: Wright State University 

In article <1992Aug28.180801.25667@ctr.columbia.edu>, jerry@connection.prospect.com (Jerry Shekhel) writes:
> fheitkamp@desire.wright.edu writes:
>>> 
> and other such "last resorts".  Do you actually think that VM was invented
> for DOS?  Yes, accessing disk is slower than accessing RAM chips, but it's

	The first VM implementation that I'm aware of is VMS on VAX. 
	I have never researched the history of VM.  Perhaps you have.
	Care to share?

	One interesting thing I read (can remember where, but not here!)
	was that the PDP11  had segmented memory.  From the article I
	got the impression that the early Intel chips were sorts of
	'clones' of a PDP11 architecture and the PDP11 was largely
	considered a failure in computer evolution.


> a lot better than having the machine hang or crash in an out-of-memory
> condition.

	Well, I agree with you.  I just don't see a VM or nothing at all
	urgency.
> 
>>
>>	Even extended and expanded memory won't help, because you can only
>>	store data.  In the MS-DOS world you have 4 kludges to get around
>>	lack of flat memory model: VM, extended memory, expanded memory,
>>	and overlays.
>>
> 
> You are dangerously uninformed here.  Software memory access protocols
> such as XMS (extended) and EMS (expanded) have nothing to do with Intel's
> segmented addressing; they have to do with the 8086 only having 20 address

	Why I'm I dangerously uniformed? And where did I say EMS and XMS
	had anything to do with segmented memory?  I think just about 
	anybody with an objective viewpoint would agree to at least
	XMS and EMS being kludges.  Segmented memory is another story.
	Intel sells it as a form of memory protection.  But since Intel has
	decided that Motorola and Digital were correct enough  that they 
	implemented a flat memory model in their latest processors...

	I am not an Intel basher.  They made some judgement calls that
	turned out to be questionable, but hey, thats the price you pay
	for being the first.  Motorola, obviously made another judgement
	call when they broke with the 6800 series on the 68000.

> lines.  16-bit OS/2 (1.x) uses segmented addressing, and can access 16MB
> physical RAM (more virtual).
> 
> VM a kludge?  Nope, it's a necessity, as far as I'm concerned.
> 
	Like I tried to say.  Important: yes. necessity: no.

>>
>>	I don't know why people keep complaining about this, all you need
>>	to do is use the subst command.  I will look it up for you:
>>
>>	subst a: b:\                                              
>>
> 
> This won't work for self-booting programs like the OS/2 installer.  The
> BIOS normally reads drive A for booting.  Some proprietary BIOS's allow you
> to switch this through the ROM-resident setup program, others don't.
> 
>>
>>Fred Heitkamp,  ** Not an organization. My opinions only **
>>
> --
> +-------------------+-----------------------+--------------------------------+
> | Jerry J. Shekhel  | Molecular Simulations | Time just fades the pages      |
Fred Heitkamp,  ** Not an organization.  My opinions only **
> | Drummers do it... | Inc.  Waltham, MA USA | in my book of memories.        |
> |    ... In rhythm! |     (617) 890-2888    |              -- Guns N' Roses  |
> +-------------------+-----------------------+--------------------------------+
> |           ...! [ princeton mit-eddie bu sunne ] !polygen!jerry             |
> |                            jerry@polygen.com                               |
> +----------------------------------------------------------------------------+
Jerry,  what does Polygen do?  Just curious.