Re: Virtual Memory

[Stephan Haslbeck <haslbecs@informatik.tu-muenchen.de>]

On Wed, 15 Feb 1995, Christian Lynbech wrote:

> I do not think that anybody wanted to say that *any* sort of VM
> system is principally *impossible*.
> 
> But for a VM system to be really usable, it must be transparent to the
> programs using it. The issue at hand is not how to write programs that
> can exploit a VM system, but how to integrate existing code. And for a
> transparent solution, there is no alternative to some sort of MMU
> support.

That's just the point! If we leave all as it is, some (many?) programs
have to be rewritten to use their own strategy of swapping, e.g. the gcc.
If MiNT gets VM, at least the 68030 owners can use it and let more and 
bigger programs run. The people with an 68000 only won't even acknowledge 
it. They will do just the same as before.

 
> Imagine the mess one would have to go through to change all the many
> megabytes of non-trivial GNU code, let alone maintaining it against
> updates. And the binary-only programs are of course completely at a
> loss.

Change all existing sources -- Does this someone voluntarily? No? :-))
 
> Even having to recompile programs for a real MMU VM system and make
> separate distributions would definitely be a pain, and leave a bunch

If it is a real VM system, you don't have to recompile anything. (Perhaps 
some older programs that do illegal things).

Ciao,
Stephan 

+------------------------------+-----------------------------+
|      Stephan Haslbeck	       |    Fachschaft Informatik    |
|       Agricolastr. 61	       |   Technische Universitaet   |
|      D-80686 Muenchen	       |      Muenchen, Bayern	     |
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