threads in test stand calling labview vi's

[mdcoco]

I am trying to run mutliple threads in test stand. I am setting up the test stand sequence call to execution : use new thread and setting up the call appropriately. When this sequnce call is run I can see multiple threads being run when CVI or other test stand calls are being initiated in the test stand sequence. However when I am trying to call a labview vi in a thread this labview vi does not open in a new thread and runs in the same thread. Only after the labview vi completes a new thread then opens. What is causing labview not to enter a new thread when the test stand sequence is executed? When this is executed all calls should should be running everything in a new thread. Is there a setting in test stand or labview on the high end that is not allowing this new thread to open as expected.

Mark      

[Daniel-E]

Hey Mark,

One thing that could cause this is if the VI is set to be non-reentrant. This means that only one copy of the VI can be loaded into memory at a time. To change the setting, open the VI and go to File > VI Properties. In the Execution category you will see an option to set the VI to be reentrant. I would start with setting this, and then let us know if you still run into the same issue.

[mdcoco]

I did modify the vi to reentrant and it still does not allow test stand to open a new thread. Something is preventing a new thread to open when any vi is being called. Any other suggestions?

Thanks

Mark

[Daniel-E]

Hey Mark,

Are you using the LabVIEW Dev environment or the Run-Time engine as your adapter? Also, does this happen only with a specific VI, or with any VI that you try to run?

[mdcoco]

Hi Dan

Thanks for helping. I am using the Development System (Active Version:11.0 (2011)(32 bit). This happens with all vi's.

Thanks

Mark

[dug9000]

What makes you think a new thread is not opening? What exactly is the behavior you are seeing that is not what you expected?

Make sure all VIs and subvis that vi is calling are marked as reentrant. If a VI is not marked as reentrant, then LabVIEW will only allow one call into the VI at a time.

-Doug