Re: 100% CPU with ntvdm.exe

I have a fairly old DOS data logging application that I still use.
By setting the priority of NTVDM to LOW the problem goes away.
NTVDM will still appear to use all available CPU time, however any other
process that needs CPU time will prempt the DOS mode NTVDM emulator.
Probably not a M$S recommended solution, but it works for me.
I should add that all I am collecting is weather data, so if it's a little
slow it does not matter. This shold not be used with anything like a near
real time control system.

"BillW50" wrote:

>
> "H. M." <aa777@xxxxxxxxxxx> wrote in message news:O7ZsNufwFHA.3768@xxxxxxxxxxxxxxxxxxxxxxx
> Date: Mon, 26 Sep 2005 03:05:48 +0900
>
> > Hi there.
> >
> > Win2K, SP4
> >
> > I have one DOS program when I use it, the CPU indicator goes to 100%.
> > Looking at the processes tab of Task Manager, it's always "ntvdm.exe" that
> > consumes the whole CPU power.
> > Moving around to other apps becomes so slow and sluggish.
> > Several seconds after that DOS program loses the focus, the CPU usage goes
> > back down to normal even though
> > the DOS program still running. Go back to the DOS program, the CPU goes up
> > again.
> >
> > Other DOS programs I have don't have the same behavior.
> > Any idea.
> >
> > Thanks.
> > Hosam.
>
> Got the PIF Properties under the Advance tab checked for the
> background for this DOS application? That should help, although the
> application won't run in the background anymore if that is
> important.
>
> Other than that, some DOS programs don't share the CPU fairly under
> some OS like Windows 2000, XP, and OS/2. As the OS thinks such
> things as reading the keyboard buffer while the DOS application is
> doing nothing is something useful that the DOS application needs to
> do. OS try to figure such CPU tasks are not important (as the OS
> handles this task for the application anyway). But some DOS
> applications are written in a way that the OS just doesn't get it.
>
> So what does this DOS application do anyway?
>
>
>
>
> Cheers!
>
>
> ______________________________________________
> Bill (using a Toshiba 2595XDVD & Windows 98SE)
> -- written and edited within WordStar 5.0
>
>
>
.

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