Re : Re: multithreading

[Sadok]

Hi,

How to use multithreading in LabVIEW?

Is the attached diagram works in multithread?! what's lack? because when I tested it, it works sequentially

[Mathan]

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Sadok wrote:

Is the attached diagram works in multithread?! what's lack? because when I tested it, it works sequentially

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Remove all the while loops and sequence structure. It will work as you expected.

Message Edited by Mathan on 05-12-2009 06:22 AM

[Sadok]

In the begining I did like you ve said but it worked sequentially! not really in prallel?? how to do please! especially that functions that want to execute in parallel  takes a time and cantain loops and sequences..

[AdnanZ]

For the subVI, go to File -> VI Properties -> Execution and check Reentrant execution.

[johnsold]

Perhaps your DAQ device does not accept parallel access.  If your loops were doing things which did not require shared access to a resource outside the CPU, they would probably mutlithread.

Lynn 

[AdnanZ]

Oh that's a good observation by Lynn. Before you check the re-entrant option, be sure to ensure that all shared resources are protected (possibly by using sempahores).

[Ben]

Rather than letting each loop at the port seperately like you have done.

 

I would sugget you look at my Action Engine Nugget where I used the challenge of writting to a DIO port from multiple threads as illustrated here.

 

By use the AE approach the semaphore "comes along for the ride".

Have fun!

Ben