From: fesenko AT po DOT pacific DOT net DOT sg (FVR)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: CWSDPMI for Gb of VM?
Date: Wed, 29 Jan 1997 17:14:21 GMT
Organization: A user of Pacific Internet
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Message-ID: <5cm83i$2sg@newton.pacific.net.sg>
References: <5cgtcp$3hs AT newton DOT pacific DOT net DOT sg> <32ebdef1 DOT SANDMANN AT clio DOT rice DOT edu>
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To: djgpp AT delorie DOT com
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<SANDMANN AT clio DOT rice DOT edu> wrote:

>> When you write 2Gb of virtual memory, what is the ratio RAM/HD in this case?

>This would be 2Gb of disk based storage in addition to the RAM you have.  But
>I just did some calculations, and it seems the small model will break at
>around 1.3Gb of disk based storage (due to data+bss+stack > 64K).  Since I
>find it highly unlikely anyone would want to suffer through that much 
>paging, I won't worry about fixing it (which wouldn't be too hard).  The
>page tables themselves would also start paging at over around 500Mb of total
>memory space, which will slow things down also.

>> And is it easy to change dalloc.h?

>Change a documented constant, and rebuild everything.  Since the larger
>sizes haven't been tested in over a year, things may have been broken.
>In particular, the latest versions don't link to the borland libraries at
>all, so a long integer operation call may be missing, or may be coded with
>assumptions in start.asm which don't apply.  So great care would be advised.
>I suspect an increase to 255Mb of disk based storage wouldn't cause many
>problems, since long integer arithmetic would be avoided.

I'm sorry for misunderstanding, what I really am interested in is the
ability to use more than 128Mb of RAM without any paging to hard
drive.
I know that there is NEVER enough RAM for a programmer, but anyway ;-)
My PC can support up to 512Mb of RAM and I beleive this is not a
limit. And I also have a memory manager which supports 256Mb of RAM
(if anyone is interested, e-mail me).
But I'm looking for large amounts of RAM not for pure enjoyment (as
some of my friends do)  ;-)

So any suggestions on increasing the amount of RAM adressable under
CWSDPMI are welcome!

Victor Fesenko
fesenko AT pacific DOT net DOT sg