So he has 1000 devices at 20 locations, but the cardinality is now 1000*20??? Why, is each device reporting from all 20 locations?? What type of math is that?
Time-series databases are optimized for performance based on having an index for each label/type of value. That inversion allows for a tremendous amount of values to be captured and reported against with low latency, but with the trade off of having less permutations available for scale. The same applies to Prometheus, Graphite, etc.
