A few companies ago, we were (essentially) a TSDB marketed toward network performance in particular. We had some large telecom companies as customers. We stor

A few companies ago, we were (essentially) a TSDB marketed toward network performance in particular. We had some large telecom companies as customers. We stored all the time-series in UTC, but the analytics data shifted by an hour twice a year. This caused a whole lot of false alarms for about a week following both time changes. This was a solid ten years ago. I don't think the problem was ever solved in the general case. We wrote them a script that support would manually run and shift all the analytics forward or back by an hour.