I know about the Thanos problem, and it's one of the things I didn't really like about it using the prometheus storage format. It does work in m3db. Following

I know about the Thanos problem, and it's one of the things I didn't really like about it using the prometheus storage format. It does work in m3db. Following are the on-disk sizes of one replica: 2 weeks at 15s res: 90G 2 months at 1m res: 160G 3 months at 5m res: 60G EDIT: The only thing is that m3db doesn't really downsample. You just create one namespace (table) for each resolution, and set the m3coordinator up so that it writes to each at the wanted interval, then set up a different retention for it. (this way you have duplicates in recent data) M3 namespaces aren't set up for a specific resolution. The writer decides and you can write various series in different resolutions to one namespace in theory.