Tag change script thread mode

Ignition
2

  1. There is a single thread pool for all tag events. Three threads by default, IIRC. Can be set at gateway startup with an additional java param in ignition.conf, but I don’t recall the precise syntax.

  2. Events that come in while a prior event is still running are queued. If the script doesn’t “catch up”, excess events are lost. The queue is five per tag, IIRC. I don’t think that can be changed.

If you need more reliable events for specific tags, use a gateway tag change event in a project, not a tag event on the tag itself. Different thread pool, unlimited queue, and other threading options. Naturally, unlimited queuing on a run-away script can yield other problems.

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