Path: utzoo!utgpu!watserv1!watmath!att!cbnewsk!markg
From: markg@cbnewsk.att.com (mark.r.gibaldi)
Newsgroups: comp.windows.ms
Subject: Re: Win3.0 - More questions
Message-ID: <1990Jun12.140525.7945@cbnewsk.att.com>
Date: 12 Jun 90 14:05:25 GMT
References: <9906@rouge.usl.edu>
Organization: AT&T Bell Laboratories
Lines: 29

In article <9906@rouge.usl.edu> pcb@gator.cacs.usl.edu (Peter C. Bahrs) writes:
>Round 2 of questions/comments:
>
>In general WIN 3.0 is awesome! (wrt win386, and all of my X envts.)
>
>1) Does win3 give each dos application a virtual 8088 machine when in
>   enhanced mode?
>   I have 9 mb memory (2 real and 8 swap) available and can only
>   run 1 copy of edix and 1 procomm...then is says out of memory,
>   kill an application.  Sooooo, the answer to this questions appears
>   to be :  ?? no, they still share 640k. 
>

Hmm...  In systems (OS) that use paged virtual memory as does Win 3.0, virtual
memory on disk does have limitations.  Programs have a certain number of
memory pages which MUST be held in RAM in order for the processing to
continue, or be continuable.  This is called a "working set".  If the
working set of your active programs exceed the amout of RAM that you have,
all the virtual memory in the world won't do you much good.  The above
example does not prove that Windows 3.0 does or does not use virtual machines
as advertised.  It could be merely that the combination of Win 3.0 and the
active DOS apps had a total working set greater than could be held by
Peter's installed 2mb of RAM.  I think we need to hear from some people
who have large amounts of memory installed.  I have the same setup as
Peter on a 25mhz 386.  However, I plan to put in much more RAM shortly.

Mark R. Gibaldi
AT&T Bell Laboratories
mrg@cbhlp.att.com