[comp.sys.ibm.pc] Interpreters That Run In EMS Memory

Will@cup.portal.com (10/26/89)

How difficult would it be to put the executable code of a language
interpreter into EMS (LIM 4.0) memory?  Can someone tell me what the
costs/benefits of this approach would be?  (i.e., how much would
performance suffer? how much more difficult to program?)  

I realize that some of you do not use MS-DOS very much, so let me 
explain that EMS memory is page-swapped memory (it's basically a 
kludge that is used to get around the 640K addressable memory limit 
using the 80X86 processors in real mode).  If you are wondering 
why I am asking this question at all, suffice it to say that I have
an application that requires an interpreter that takes up as little
memory as possible when the interpreter is not running, but the
interpreter needs to be loaded and ready to execute while other
applications are executing.  

Also, what C libraries are out there to assist in doing this, and
does anyone have a comment on the quality of those products?

Will
[Mapping in EMS 4.0 and running code there works, and once the pages are
mapped in the memory is usuall as fast as anything else.  I have never seen
anything to help with the swapping other than systems like Desqview. -John]
[From Will@cup.portal.com]
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