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- ID:DM Memory usage by DESQview
- Quarterdeck Technical Note #111
- by Dan Sallitt
-
- Q: How much memory does DESQview use?
-
- In its unmodified state, DESQview 2.2 takes up, somewhere in
- memory, between 145K and 180K. The differences are due to
- various drivers that DESQview may or may not load depending on
- its setup configuration and the hardware on which it is running.
- The low-end figure of 145K can be reduced a bit by throwing away
- features in DESQview's Setup. On a machine with only 640K of
- memory, all of DESQview's code resides in conventional memory.
-
- If your machine has extended memory, DESQview can place 63K of
- its code at the beginning of extended memory with our QEXT.SYS
- driver and our XDV.COM loader.
-
- If your machine has any kind of expanded memory, DESQview can
- place 32K of its code (slightly more on a VGA system) in the EMS
- page frame with XDV.COM, switching this code out of harm's way
- when the page frame is in use. When both extended and expanded
- memory are present, DESQview can therefore remove about 95K of
- itself from conventional memory.
-
- If your machine's expanded memory permits the mapping of
- additional pages of expanded memory between 640K and 1024K,
- DESQview can place even more of its code in high RAM with
- XDV.COM. On a machine that provides enough free mappable pages
- between 640K and 1024K, it is common to observe that DESQview
- leaves little more than 1K of its code in conventional memory.
-
- (When computing DESQview's overhead in running a program, you
- should remember that a certain amount of memory - 9K, on the
- average - is taken as overhead when a window is opened. This
- figure can be decreased a small amount by manipulating the Change
- a Program menus for the program in question.)
-
- Copyright (C) 1991 by Quarterdeck Office Systems
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