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Re: [MiNT] virtual memory



Hello!

> With a (current) limit of 512MB physical memory which you want to map in
> kernel space, that leaves us 512MB virtual memory, or 3.5GB for 'clean'
> programs that can use the whole address space.
> 
> Or do you have a better proposal?

To say it again, to seperate user address space and kernel address space
expand the available virtual address space but there are to much negative
side effects.

First you cannot use any longer any existing xdd/xfs and especially TSR
programs. All must be first modified to copyin/copyout the data to and
from user space. This may be possible with the xdd and xfs but for TSR it
will be really difficult.

Second: Due to the nature of seperated adress space any copy action is not
a simple bcopy but a really expensive page location calculation/temporay
mapping/copying/unmapping instead.

And at last how can be Super() handled in a correct way with different
user and kernel space?

Not to speak about all the nice tools that everybody of us have in his
auto folder ...


Tschuess
   ...Frank

--
ATARI FALCON 040 // MILAN 060
-----------------------------------------
http://www.cs.uni-magdeburg.de/~fnaumann/
e-Mail: fnaumann@freemint.de