Program 3x faster on Win98 or XP than on Win2000 !?

  • Thread starter Thread starter Carsten Fuchs
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Carsten Fuchs

Dear group,

one of the programs I'm currently developing is a simple Win32 based,
character mode (command console) application.

It does nothing but load a file for initialization, and then computes
several minutes for its output, using no resources except RAM and CPU.

I'm also measuring the time that the program takes to complete, and
found something strange:
Running the program under Win98 *OR* WinXP takes only about a THIRD(!)
of the time that is taken under Win2000 SP4 !
(My program also logs the time it has taken until completion,
otherwise I had not even noticed...)

All test cases operate on the *same* hardware, the *same* program
executable, and the *same* input data and conditions.
In all cases no other programs are (knowingly) running.
System Monitor shows 100% CPU utilization for my program in all cases.
Only the OS differs.

I've also tried to run the program with Win2000 booted into fail-safe
mode, in order to reduce driver problems as much as possible, but the
program was as slow as with normal boots.

The problems can also be observed with many other programs (e.g.
compilers).

I've exhaustively searched the web for possible problems, and tried
out everything that seemed to be related to the problem.

However, all that I found is that the CPU wastes cycles, or slowed
down for any unkown reason.

I'd much appreciate any help, hints or ideas in identifying what's
wrong with my system, as I'd like to stay with Win2000 if possible.

Thank you very much!

Best,
Carsten
 
Bob said:
Polling the keyboard? (for ctrl-break fer instance) That's a killer on
an NT box.
Click to expand...

No. Never. All I do is floating point math and other calculations.

Must be something else...

Best,
Carsten
 
No, not you intentionally. The compiled program doing it as a default
setting. Also you could try TameDos.
 
Bob said:
No, not you intentionally. The compiled program doing it as a default
setting. Also you could try TameDos.
Click to expand...


Bob,
thank you very much!
I'm using the free OpenWatcom compiler (http://www.OpenWatcom.org),
and the problems disappeared entirely when I experimentally compiled
the same app. using VC++ 6.0.

Will work that out with the compiler guys now. ;-)

Again, thank you very much for your help!

Best,
Carsten
 
You're welcome, glad it's sorted out.

Carsten said:
Bob,
thank you very much!
I'm using the free OpenWatcom compiler (http://www.OpenWatcom.org), and
the problems disappeared entirely when I experimentally compiled the
same app. using VC++ 6.0.

Will work that out with the compiler guys now. ;-)

Again, thank you very much for your help!

Best,
Carsten
Click to expand...
 
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