Category : Alternate Operating Systems - Quarterdeck DesqView, CP/M, etc
Archive   : QWAUG92.ZIP
Filename : MEMSIZE.TEC

ID:MZ Memory Size Field Explanation
Quarterdeck Technical Note #129
By Joe Wilder

The Memory Size (in K) field in Change-a-Program is a number set to allow
DESQview the opportunity to tell the user whether there is enough memory to
open a particular program. That is to say, DESQview compares the number in
the Memory Size (in K) field to the Largest Available fields (conventional and
expanded) in Memory Status (which varies according to which and how many
programs are running). If the Memory Size in K field is larger than BOTH
conventional and expanded Largest Available, DESQview puts a message on the
screen telling the user there is not enough memory to open that window. At
this point DESQview hasn't even tried to open the program. It's just telling
the user there's not enough memory according to the user's specification to
try to run the program. This is useful to prevent a program from attempting
to run and then freeze for lack of available memory. Note: Programs running
under DESQview require 9K of so extra memory for DESQview to manage their
windows.

The Maximum Program Memory Size (in K) field is the amount of memory which
DESQview will try to acquire for the particular program if available. If this
number is higher than the Largest Available fields in Memory Status (both
conventional and expanded), DESQview will acquire all of what Largest
Available in MS reads whether the program to be run needs that much memory or
not.

If there is ample memory on the computer you might want to set Maximum Program
Memory Size to some very high number that you know is beyond what is actually
available. This, of course, may not be desirable for users of machines with
limited memory who are trying to multitask a couple of small programs. They
may want to try to squeeze multiple small programs into the first
(convertional memory) partition, which would be completely used up if the
first program's Maximum Program Memory Size (in K) was set higher than
necessary.

Maximum Expanded Memory Size (in K) is used to limit a program in the amount
of expanded memory it may use. If Maximum Expanded Memory Size is left blank,
a program may take or leave as much expanded memory as it wants. If a number
is placed in this field, the program may take as much memory as it wants up to
that number. If a program doesn't use all the Expanded memory allocated by
this field, the rest is still available for other uses. This is especially
useful for running programs that grab all of the expanded memory available on
startup, leaving nothing for other programs. This convention is not to be
confused with the usage of a blank with the Maximum Program Memory Size (in
K). In the case of Maximum Program Memory Size, a blank means this field will
default to the number in Program Memory Size (in K) on the first screen of
Change-a-Program.


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*This technical note may be copied and distributed freely as long as it*
*is distributed in its entirety and it is not distributed for profit. *
* Copyright (C) 1991 by Quarterdeck Office Systems *
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