Questions about "appRunning" duration and timestamp issues

Hi, I'm trying to sanitize our data and in the process, piece together just how some pieces of core analytics events work. First of all, I have some sessionids for which multiple appRunning events have been fired several minutes apart in which the duration field hasn't increased at all. In other cases, I'll see sessionids where appRunning events may be firing for hours or days at a time, correctly updating the duration from event to event (based on looking at the differences in timestamps), however the user will have no custom events for this session (which would mean, in our case, that they didn't do anything other than get to the main menu). My guess is that the appRunning duration is actually recording the duration that the app is in focus, and that the second group of outliers i mentioned simply represent times when the user opened the application and left it running without minimizing it. Is this correct, or could something else be going on?

The second set of questions i have relate to timestamps. I fully expect the users system time (ts) to occasionally be inaccurate, representing issues with their system clock. However I was surprised to see that the submit_time (server time?) can also often be inaccurate; for example, I've seen session where the appStart event for a given session has a submit_time of hours, if not weeks greater than the other events associated with that session. Is this behavior associated with outage periods in the analytics service? What exactly does "submit_time" represent; is this actually the time at which data is processed, rather than the time it's received by the server?

On the more rare side of things, it looks like the ts and submit_time fields may occasionally go from being out of sync to identical from one event to the next. I guess it's possible for the users system clock to update / correct itself between events; could this be what's happening?

Thanks

 

It could be that the user was offline and cached the events locally. Then subsequently went online, played the game again, and the events were sent.

 

Interesting, that could certainly explain some of what we're seeing. But could that account for appStart events having a later timestamp than the custom events for a given session? I would expect the timestamps on those to be fairly close in proximity, although in some cases it's off by weeks. Is there a difference in how core events and custom event timestamps are created?

 

I don't believe so, we would need specific examples. Please open a support ticket here https://analytics.cloud.unity3d.com/support/ and provide steps to reproduce. We may ask if we can perform a Raw Data Export in your account.