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Is VMWare Good Enough...

... to replace a "real" testmachine?

I have just spent a few days testing a problem that I found when testing our program on a VMWare system. I found that  when running on Windows 98 inside VMWare (3 and 4, AMD and Intel Processors) our Visual FoxPro 7 based program would cause an Invalid Page Fault while launching.

The program works fine on NT4, 2000, XP and 2003 inside VMWare - and Windows 98 on a "real" computer.

I suppose my question is: "Has anybody ever had problems running a program on VMWare that would work fine on a real computer?" particularly VFP based programs?

Chris
Thursday, July 31, 2003

I've never had problems that only occurred in VMware or visa vera ;-)
If you can't replicate a problem in one that you can in the other, and you suspect that it's an issue related to VMware, try physicalizing the guest (see my post below)...

Israel Orange
Thursday, July 31, 2003

That way you can eliminate VMware as the source of the invalid page fault...

Israel Orange
Thursday, July 31, 2003

Hi Israel Orange, but by my logic, installing a brand new blank Win98 (SE Version of MSDN Disc 0011, I even left off the VMWare tools install) on VMWare and getting the problem and then installing the same verision of windows on a real computer with all the same settings and not getting the problem kind of points the finger at VMWare.

Would not "physicalising the guest" be the same as a fresh install?

Thanks in advance for any further info Israel Orange.

Chris
Thursday, July 31, 2003

D'oh!
Excuse the brainfart, Chris.

Israel Orange
Thursday, July 31, 2003

One thing tho, more rational than my previous suggestions: try running the '98SE guest in a different host than you are using, and see what happens?

Israel Orange
Thursday, July 31, 2003

You already know that it's VMware, this way you'll know if it's any VMware setup, or just VMware on XP, say, or whatever...

Israel Orange
Thursday, July 31, 2003

Honestly I spent half an hour yesterday searching the VMWare site and didn't find a thing... Just now I searched just once and found this: http://www.vmware.com/support/kb/enduser/std_adp.php?p_faqid=901

I suppose VMWare isn't perfect... I'm happy now anyway, let this be a lesson to the rest of you.

And thanks for the tips anyway Israel.

Chris
Thursday, July 31, 2003

Although it is strange that FoxPro is stuffed only in 98 and not the rest though.

Chris
Thursday, July 31, 2003

Chris, check this out too, you may find it useful:
http://groups.google.com/groups?q=vmware+group:*vfp*&hl=et&scoring=r&selm=17775718.0110080858.561cb0a9%40posting.google.com&rnum=1

Israel Orange
Thursday, July 31, 2003

Nah, keep looking into your setup. I think your VMWare setup and the physical box are not the same ...
VMWare only provides virtual hardware drivers. The rest is whatever you installed. Do not install VMWare tools inside your W98, work with the slow system but at least you know it is "original".

Mr Curiousity
Thursday, July 31, 2003

"Would not "physicalising the guest" be the same as a fresh install?"

Well, I should read more carefully. "Physicalising" the guest should be more comparable than fresh install because there might be subtle but important differences. You'll have to update the drivers once you go physical, and that can hide the issue.

Mr Curiousity
Thursday, July 31, 2003

Hi Mr Curiosity. That article I linked to did fix the problem http://www.vmware.com/support/kb/enduser/std_adp.php?p_faqid=901 , and the link that Israel provided actually has the reason (Although I have no idea what SIDT does, it isn't in my 8086 book.)

I suppose I will just have to live with testing on 98 with Acceleration Disabled (I don't think it is a good idea to modify the runtimes for testing.)

Chris
Thursday, July 31, 2003

Chris

Thanks a lot for the update! It turns out VMWare is not as infallible as I once thought :-)

At a presentation they mentioned that running OS-VMWare-OS-VMWare is flaky (VMWare doubled), so I believe they still have few issues to iron out ...

Mr Curiousity
Thursday, July 31, 2003

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