Tag Change Missed Events

In fact I have been talking about these events only! So these events are not restricted to 3 threads and 5 event queues in each and there are no missed events! Is that correct? How does it work?

One more question I had on these event is how to register tags for these events thru scripts ? As I understand we can only register variables thru the scripting console. Is there a way to register tags thru scripts for these events?

(sorry for barging in this discussion, but it is interesting topic for me as well).

No.

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As Kevin noted, there's no queued event limits for those, so short of a gateway out-of-memory error, they don't miss. (And Gateway OOM breaks so much throughout the server that a missed event would be the least of your worries.)

Strictly speaking, project-based tag change events can miss when a project updates from a designer. You can tell that it updated, as scripting restarts and the event fires its ā€œinitialChangeā€ again.

I may be kind of late to the party but since no one mentioned using system.util.invokeAsynchronous() to decouple data logging from the tag event queue. Even this approach will hit a wall if the transactional frequency is too ā€œgregariousā€.

@Kevin.Herron, @pturmel I would be curious to hear your thoughts.