I'm having trouble with an event frame-generation analysis sometimes failing to generate event frames (EFs). I've already searched for known issues and other asked question in the forum, but I haven't been able to find anything that helps.
The analysis works 99% of the time, creating an event frame and sending out notifications as it is designed; sometimes, however, I find out after the fact that the analysis failed to capture an event that should have yielded an EF. In all of these instances, running the Preview Results function shows the event, and recalculating/backfilling the analysis creates an EF.
The analysis scheduling is set to event-triggered. It is configured with two start triggers and no end triggers. Each event frame is generally open for ~20 seconds when it works.
One other relevant note is that this particular analysis runs on several assets simultaneously. Within the past couple days, several event frames have been created by the analysis, with all of the EF-generation failures occurring on asset X. A couple of the events at asset X were successfully captured by the analysis, but most failed.
I have a few questions on this as I'm trying to better understand how the AF analysis works and figure this problem out:
1) How does the Preview Results function in AF analysis work? Does it recalculate the analysis without creating EFs, or does it just show a list of the events that were found by analysis previously?
2) How can I tell if my analysis ran successfully? Does a positive finding in Preview Results indicate that the analysis ran at the time of the incident and just failed to capture the event, or do I need to access the analysis logs to get this info?
3) Is intermittent EF-generation failure as I've described a known issue with PI analysis 2018?
4) Is there anything that I can do to prevent these failures in the future?