GTFS realtime update interval
Hello!
We are currently using the GTFS realtime vehicle position updates to track the SL bus positions in Stockholm. From our last question here, we were told SL can provide their position every other second. 
However, when we are measuring the vehicle position from our monitoring, we can see that while most updates are indeed at 2s(84%), there are many occassions where it is 3-4s(14%) with outliers at 5-7s(2%).
Is this the expected behaviour of the system or are there any issues currently ongoing with the GTFS update frequency of SL?
Thank you for your help!
Victor
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How are you measuring these update frequencies? By looking at the update timestamp for vehicles, or for the entire file?
Regards,
Bert
So we have a sudden jump of 3 second interval (file content of all *677 are the same.
The larger delays (2%, 5-7s) are most likely due to high system load at night when static data is updated in the background. The smaller delays are related to race-conditions when working with these frequent updates.
Are these minor delays, or the larger delays, causing any issues for your use case? In the example above the "sudden jump" is a file being available one second later than planned, which does not interfere with the use cases which are currently known to us. This in turn causes this issue to be relatively low on our backlog.
Regards,
Bert