This affects the delay in Event\Trigger tags. KCS: Delay in Event Points.

The largest and most variable delay seems to come from the time the event is written to the PI Server and the time the interface (UniInt) picks, which is between 0ms-1,000ms from my testing. This seems to be due to a built-in, hard-coded, delay in how often UniInt checks for events from the PI Server update manager. The serviceeventsx function that is part of the main UniInt loop only checks for new events once a second; this means that sometimes there is no delay if the event happens to come in right before we check for new events, and sometimes it can be up to a 1 second delay if the events happens to come in right after our last check for new events. I can also see this delay going past 1,000ms if the interface is doing a lot of work and slowing down the main UniInt control loop, or if there's significant network lag between the interface machine and the PI Server, or if the PI Server is under unusual load.