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- ID:WZ Maximizing Window Size in DESQview
- Quarterdeck Technical Note
- by Dan Sallitt
-
- First, the basics. If you have any kind of expanded memory or
- if you have extended memory and have placed DESQview's QEXT.SYS
- driver in your config.sys file, you should be starting DESQview
- with XDV.COM instead of DV.EXE. We recommend in our manual that
- XDV.COM be renamed to DV.COM, in which case you can simply type
- DV at the DOS prompt and be assured that the .COM file is being
- used. Failure to start DESQview with the .COM file is the most
- common reason that window size falls short of the user's
- expectations.
-
- If you are starting DESQview with the proper executable file and
- you still can't open a window as large as you think you should be
- able to (our documentation includes a table that gives you an
- idea of what to expect), there are several common reasons.
-
- 1) Drivers and terminate-and-stay-resident programs (TSR's)
- loaded before DESQview may be taking more memory than you expect.
- The amount of memory available to a window inside DESQview
- decreases as more memory is used up before DESQview; this is true
- no matter how much extended or expanded memory is on the system.
- If you want to decrease this overhead, you have a few options.
-
- a) Streamline your CONFIG.SYS and AUTOEXEC.BAT files.
-
- b) Load some programs inside DESQview. If a TSR doesn't
- have to run before DESQview (obviously, some programs, like disk
- caches and print spoolers, wouldn't serve their function when
- loaded inside a window), it's much more memory-efficient to let
- DESQview manage it. Even some CONFIG.SYS drivers can be loaded
- inside a DESQview window using DESQview's DEVICE.COM utility.
-
- c) If you have the Quarterdeck Expanded Memory Manager-386
- (QEMM-386), or if you have expanded memory that can be mapped
- freely in the area between 640K and 1024K and you have
- Quarterdeck's QRAM.SYS utility, you may be able to decrease your
- memory overhead by loading devices and TSR's into high memory.
- (You may even be able to do this if you have an expanded memory
- manager with its own high-loading capabilities, like All
- Computers' ALLEMM4.SYS for the All Chargecard.) Any unused
- address spaces between 640K and 1024K (different systems will
- have different amounts of free space in this area) can be filled
- with expanded memory and used to run small programs that would
- otherwise occupy conventional memory.
-
- It is worth remembering that DESQview loads itself high (with its
- XDV.COM driver) in the same areas that QEMM-386 and QRAM use to
- place drivers and TSR's. If you place enough programs in high
- memory before running DESQview, you will sooner or later reach a
- point at which the high loading no longer increases your window
- sizes inside DESQview, because DESQview will be forced to start
- loading pieces of itself in low memory when high memory gets
- crowded enough. At this point one can sometimes get creative in
- finding new places to put RAM in the reserved memory area between
- 640K and 1024K. Which brings us to the second reason that memory
- figures inside DESQview may be falling short of expectations.
-
- 2) On an extended or expanded memory system, less of DESQview may
- be going into reserved memory than is possible. To evaluate this
- situation properly, it's helpful to have some experience with
- DESQview's normal use of reserved memory. A few rules of thumb
- apply, however.
-
- a) On 80286 systems that have the first 64K of extended
- memory free, DESQview's XDV.COM loader can put 63K of DESQview
- code into extended memory if the QEXT.SYS driver is in the
- CONFIG.SYS file. On 80386 systems, QEMM-386 obtains the QEXT
- effect automatically for you; if you are using another memory
- manager, you may wish to tell it to leave behind 64K of extended
- memory and use QEXT.SYS. (Compaq's CEMM is also able to obtain
- the QEXT effect without QEXT being present.)
-
- b) On some expanded memory systems DESQview can put some of
- its code in unused video areas. The A000-AFFF area (640K to
- 704K) is used for EGA and VGA graphics, and should be available
- if EGA and VGA graphics aren't used. The B000-B7FF area (704K to
- 736K) is used for monochrome text, and should be available on a
- color system. The B800-BFFF area (736K to 768K) is used for
- color text (and sometimes for Hercules graphics), and should be
- available on monochrome systems. You can try including the
- appropriate areas on your memory manager's CONFIG.SYS line.
-
- c) Some expanded memory managers (notably the Intel
- Aboveboard Plus) only allow memory mapping to occur immediately
- above the expanded memory page frame. See our technical note on
- the Aboveboard Plus for information on how to maximize this
- mappable area.
-
- d) Adventurous users of QEMM-386 version 5.0 will notice
- that the command
-
- QEMM ANALYSIS
-
- gives a list of the different areas of memory that may be claimed
- for DESQview and QEMM-386's LOADHI function to use. This utility,
- which should be acted upon only after it has been run on several
- occasions after you have run the full complement of programs that
- you normally use, should give you an idea of which areas in your
- system ROM may in fact be unused and available for including with
- the QEMM-386 INCLUDE parameter. There is an element of trial and
- error to this process, but the rewards can be substantial. Even
- if you are using another memory manager or an earlier version of
- QEMM-386, it may be possible through a series of blind attempts
- to find unused ROM areas that can be included and used to
- decrease your memory overhead. The ROM area F000-F7FF, sometimes
- used only by the ROM BASIC, is a favorite area to try including;
- sometimes a slightly smaller inclusion, like F200-F7FF, is
- necessary. If you guess incorrectly, your machine may not boot
- properly, so you may wish to keep a bootable DOS diskette handy
- during this process.
-
- 3) Sometimes DESQview's Setup program contains excessive memory
- allocations that cut down on DESQview's overall memory. The two
- field that most often are abused in this regard are both on the
- Performance option of the Advanced Setup.
-
- "Common Memory" is memory used by DESQview to manage its windows,
- and the amount you need is usually proportionate to the number of
- windows you open. The default value is 17K; the minimum value of
- 13K is adequate for users who open no more than five or six
- windows at once. Few users need more than 20K of common memory.
-
- "DOS Buffers for EMS" is memory used by DESQview to manage file
- operations into expanded memory. The default value is 2K; users
- of QEMM-386 who are not on a network can set this figure to 0K
- with no loss of performance and a memory savings of about 5K.
- The value of this field can affect the speed of disk access;
- however, it is rarely worth while to choose a value higher than
- 10K or 15K.
-
- If you wish to throw away a few DESQview features, you can
- probably scrimp a few more K from the Setup program.
-
- On the Keyboard option, you can save as much as 12K if you tell
- DESQview that you don't wish to use the Learn feature. This will
- disable DESQview's very useful macro system.
-
- On the Video Monitor option, you can save anywhere from 0K to 16K
- if you tell DESQview that you don't wish to display text and
- graphics at the same time. This will disable DESQview's Video
- Options menu, prevent graphics programs from being seen when they
- are in background, and prevent virtualization of graphics.
-
- On the Performance option, you can save 2K by setting the "Manage
- Printer Contention?" field to N. (However, this field defaults
- to N.) This means that DESQview will not intervene to prevent
- two programs from printing at the same time.
-
- Copyright (C) 1990 by Quarterdeck Office Systems
- * * * E N D O F F I L E * * *