DOS program runs slow in XP

[Kass]

I have a DOS based, Siebe DMS environmental control
program at work. You must access the program through the
C:\ prompt. I can get into the DMS program in XP by
using the C:\ Prompt program, but it runs incredibly slow
compared to how it used to run before we upgraded from
Win98 to WinXP. This program accesses all the
checkpoints in the building to control heating, air
conditioning, fresh air intake, fan speeds, etc. It acts
like there is a lag time before display. For instance,
there is a clock in the program with seconds display.
Instead of the seconds ticking away like before, it might
read 05:25:20 for awhile and then suddenly jump up to
05:20:48. When I start the program in the C:\ Prompt
program in XP, I get a quick flash message about XMS
driver not installed or something, but the program does
take off. I can access all the control point windows,
just really slowly. Does anyone know why this might
happen in XP?

 

[Guest]

Hi,

Use the program compatibility wizard to run your program in a true dos
environment. The c:\ prompt isnt the real dos environment found in earlier
versions.

Regards
M. Rajesh
..Net and Windows Shell MVP
www.winxpsolution.com.

 

[xe77]

Instead of using the DOS prompt to start the program, use
a shortcut to the EXE file. You can customize the
shortcut to: 1) Allow the program access to XMS memory, 2)
Adjust the Idle Sensitivity (towards High) to allow the
program to have more foreground CPU time, 3) You can
adjust the process priorty after the program has started
to give the program more CPU quanta (time slices per
second). NOTE: MS-DOS programs aren't multitasking. When
you are adjusting the priority (from Task Manager >
Processes, adjust NTVDM.EXE) if you set it to Realtime you
risk freezing the computer or all other processes other
than the DOS program.
For more assistance: Open the Help and Support Centre and
lookup: "priority" > "Allocate system resources for an MS-
DOS based program"

 

[NobodyMan]

Hi,

Use the program compatibility wizard to run your program in a true dos
environment. The c:\ prompt isnt the real dos environment found in earlier
versions.

Regards
M. Rajesh
.Net and Windows Shell MVP
www.winxpsolution.com.

You're an MVP and giving out this crappy advice? Setting up this
program to operate in one of the compatability mode of WinXP can't
allow this OP to run the program in a "true DOS environment." The
only way to do that is to boot from a DOS boot floppy since, as I
would expect an MVP to know, XP CONTAINS NO REAL DOS MODE CODE!

 

[Stephen Harris]

You're an MVP and giving out this crappy advice? Setting up this
program to operate in one of the compatability mode of WinXP can't
allow this OP to run the program in a "true DOS environm ent."

The only way to do that is to boot from a DOS boot floppy since, as I

That would work if the drive were formatted win xp fat32. But nearly
all business computers are formatted NTFS, so your idea will not work,
leaving only xp dos emulation or a dedicated DMS machine running
maybe win95 with the option to boot to previous OS enabled (meaning
you first install dos before win95). You can't go from NTFS to Fat32.

 

[Alex Nichol]

I have a DOS based, Siebe DMS environmental control
program at work. You must access the program through the
C:\ prompt. I can get into the DMS program in XP by
using the C:\ Prompt program, but it runs incredibly slow
compared to how it used to run before we upgraded from
Win98 to WinXP. This program accesses all the
checkpoints in the building to control heating, air
conditioning, fresh air intake, fan speeds, etc. It acts
like there is a lag time before display.

In Win 98 a DOS program ran in a separate virtual machine, in 'Virtual
86' mode, running the actual 16 bit code direct. In XP it is run under
a 32 bit emulator that puts on considerable overhead, especially in
something like that. I think if you have to devote a machine to this
program (and it sounds as if you probably do) your best course is to put
it back on 98, probably making a separate partition and installing with
a third party boot manager so you could choose to boot that or the XP
at other times, and having a shared FAT 32 partition for transferring
any data across.

And ultimately look for an up to date 32 bit program to replace it.
Doing such things in DOS is nearly as obsolete as using an IBM 360

 

[Alex Nichol]

Use the program compatibility wizard to run your program in a true dos
environment. The c:\ prompt isnt the real dos environment found in earlier
versions.

You *cannot* run in a true DOS environment within XP, compatibility or
no. It is just not there

 

[David Candy]

Run it full screen. Most but not all of the slowness is from emulating the video. It doesn't need to in full screen.