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Has execution cap been confirmed to work with DOS guests? I installed DOS 5.0 and 6.20 guests on Windows XP and Ubuntu hosts, and I'm still seeing 100% CPU utilization regardless of where I set the cap.

I don't think this will work for OS's that ain't aware, they constantly pull the keyboard to see if anything needs to be done and hereby jogg the cpu, you're going to need dosidle or some sort of tool.

DOS 6.2 comes with power.exe which idles the CPU when not in use. Just add it to the config.sys and you're good to go.

Execution cap should work with all guest OSes. It is done at the host-platform level.

Yes it does and I can confirm that it does in fact work with DOS 6.2, but power.exe frees the cpu ticks when idle (no program executing).
By the way anything below 41% causes the DOS guest to stutter. I have had it as low as 20% and even with the stuttering the guest preforms as it should.

Thanks to all who responded.

Perryg,
I tried both power.exe and dosidle.exe, and they both idle the cpu when DOS is at the command prompt. However, I have to run a legacy application which does not respect the DOS I/O conventions, and they have no effect when it is running. That's why I was interested in host-platform based throttling.

May I ask what host hardware/OS you are using?

Perryg wrote:Yes it does and I can confirm that it does in fact work with DOS 6.2, but power.exe frees the cpu ticks when idle (no program executing).
By the way anything below 41% causes the DOS guest to stutter. I have had it as low as 20% and even with the stuttering the guest preforms as it should.

Hardware and OS should not matter. I am using Linux as host though.
When your application is up neither power.exe or dosidle.exe will do any good I am afraid. You see back in the day they were not concerned about the processor being run at full throttle. So when you are running the app it will be what ever you set the throttle at. Just use the CPU execution cap and find the setting that works but consumes the least amount of CPU ticks.

edelacy wrote:However, I have to run a legacy application which does not respect the DOS I/O conventions, and they have no effect when it is running.

Then you need tame(-res), which does the same but while a program is running.