Multithreading with DLL function seems to run serial in stead of parallel

The following problem was posted earlier in the Knowledgebase. I have the same problem only in LabVIEW 6.1, which is according to the solution fixed.
Am I doing something else wrong?
Problem: When I run DLLs (built in LabVIEW 6.0.x) in a multi-threading environment, it seems like my calls are being run in series
rather than in parallel. Why is this happening, and how can I fix it?
Solution: LabVIEW 6.0.x only creates 2 data spaces for re-entrant VIs that are LabVIEW DLL entry points. Therefore, only 2
calls can happen concurrently (run the same LV DLL entry point in parallel.) This means that if you launch 6
threads to run the
same LabVIEW DLL entry point, your 6 threads will run serially in pairs of two. With the release of LabVIEW 6.1, this has been
fixed to allow for a more true multi-thread capability.
Attachments:
dlltest.llb ‏199 KB

One problem is that if both threads are trying to access the same hardware resource (PCI-bus card) those accesses could be serializing the calls.
Mike...
Certified Professional Instructor
Certified LabVIEW Architect
LabVIEW Champion
"... after all, He's not a tame lion..."
Be thinking ahead and mark your dance card for NI Week 2015 now: TS 6139 - Object Oriented First Steps

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