Hi all,
I've verified all of the behavior that has been described here. The spike in CPU usage is seen in LV 8.2.1, 8.5, and 8.5.1 but not 8.20. I have however, verified that the VI is still running (add an indicator to the iteration counter). It would be a more conclusive test of course to run this with HW and ensure the external devices are still operating... ...Ok, I've tested it using a Compact FieldPoint and verified that the VI does indeed continue to run.
I have reported this behavior to R&D since it does not occur in LV 8.20. The Corrective Action Request number is 116562 if you would like to follow the status of our work.
Thank you for finding/noticing this,
David_B
Applications Engineer
National Instruments