Slowing down virtual machines

re: Slowing down virtual machines

Chad Kitching — Wed, 06 Jun 2007 22:58:03 GMT

If you really need to run dos programs that can't run on a modern, fast CPU, you could always use dosbox. It's pretty good at emulating an old, slow PC with all the quirks and limitations the old processors had. It was made specifically to run old DOS games, but it's plenty capable of running more serious apps, too.

http://dosbox.sourceforge.net/

re: Slowing down virtual machines

Benjamin Armstrong — Fri, 25 May 2007 02:17:52 GMT

question -

No, this is not possible.

Cheers,

Ben

re: Slowing down virtual machines

question — Fri, 25 May 2007 00:51:53 GMT

On a similar note, we have a legacy application that due to some insanity of the original developers checks that it is running on a Pentium III processor. The application refuses to start if it is not. We >really< would like to virtuize this application and it's server, however virtual PC and virtual server report to the client o/s the actual processor that is in the physical machine.

Is there any way to "trick" the client VM into reporting that is is running on a certain processor?

Desirable features for Virtual PC.

ewart — Wed, 16 May 2007 05:17:48 GMT

Not sure if anyone is listening.. but

1. Higher screen resolutions

Any plans for virtual PC to support more screen resolutions? I bought a 22" lcd which defaults to 1680x1050. Virtual PC does not support this resolution.. even though it supports 1600x1200. I know many share this frustratation.

2. Multiple monitor support.

Any chance of competing with vmware in this regard? I must say since v2007 at least being able to run in full screen mode now without affecting other monitors is a major, major benefit. thanks, thanks!!

3. Multiple core cpu's

This is going to be a major in the not too distant future. Limiting it to one CPU for a virtual machine is sooo restrictive. Do they even ship single core machines anymore? duals are standard now and I expect quad cores to be mainstream in the not too distant future.

ewart at ihug.co.nz

re: Slowing down virtual machines

DosFreak — Tue, 15 May 2007 15:01:24 GMT

"For gaming, I would like to have a builtin cheater/trainer support :P Any chance to get such a feature in VPC? Or in a better name... DEBUGGER"

There are DOS apps that can do this, like GameWizard. Not sure if it works in VPC though.

This has been requested many times for DosBox but it's not a DosBox priority as we are more concerned with compatibility.

Any DOS game that that runs too fast on your host PC should run just fine in DosBox.

I recently threw together a C2D machine and now instead of 15-20fps in Duke3D @ 640x480 (Athlon XP 2800+) , I'm getting 40+ fps @ 1024x768. :) Duke is fully playable at 15fps so if DosBox supported even higher resolutions I could probably get away with it. (Of course there is Jonof's Duke3D port but I bench DosBox with Duke to get a general feel of Build engine games under DosBox).

re: Slowing down virtual machines

Jonathan — Tue, 15 May 2007 11:31:09 GMT

Ah, I got bit by the "Runtime Error 200" bug of Borland/Turbo Pascal 7. At the time, many people around here used some DOS program launcher, written in TP7. Once I (as a PC technician) upgraded their machines, their program wouldn't work anymore. They were not amused. IIRC, the problem started when the second-generation Celerons (300A, 333, etc) appeared - these were the first mainstream PC processors to have core-speed cache, and thus run the timing loop too fast.

Sound like if you want slow, you should use emulation. To quote from the post:

A common request that I hear is that people want a way to create a 'slow' virtual machine. (...) emulation is much slower than virtualization - so they cannot run as fast as Virtual PC / Virtual Server can.

BTW, is it possible to change the color of links? The difference between #700 (dark red) and #333 (dark grey) is invisible to slightly color-blind people (like myself and all the males in my family).

re: Slowing down virtual machines

william — Tue, 15 May 2007 04:50:08 GMT

For gaming, I would like to have a builtin cheater/trainer support :P Any chance to get such a feature in VPC? Or in a better name... DEBUGGER :)