[baaym]

Years ago I had a Graphite installation where I configured retention policies, and the same for InfluxDB if my memory doesn't fail me.

The downsampling feature at first glance seems to serve a different use case than Prometheus was built for, which I think is observability and alerting for a relatively short time period. For systems that need to work with years of data it totally makes sense, but I don't think Prometheus is used in those cases.

Since this feature has been built for a reason however, I could be wrong

[bitwalker]

Prometheus without any supporting tooling isn't really designed for long term storage as I understand it, however it is built to support long term storage and querying via its remote read/write protocol. Prometheus will write data to remote storage, and can delegate queries to that storage, rather than using its own local storage as it does by default.

Of the various tools that expose the remote read/write APIs, I like the looks of Promscale/TimescaleDB the most so far, but other options like Thanos might make more sense if you need to collect metrics from a bunch of Prometheuses. That said, maybe you can still use Promscale/TimescaleDB with Thanos as the storage backend, I can't recall the details on its requirements though, so it might not be suitable for that case. For my own use cases though, Promscale is a great solution.

[ramonguiu]

(NB: Promscale team member)

Thanks for the positive feedback!

Is there anything in particular you are missing in Promscale to be used as a backend for multiple Prometheus instances?

We added support for multi-tenancy a couple of months ago (https://blog.timescale.com/blog/simplified-prometheus-monito...)

And thanks to a community contribution by 2nick on github Promscale can be integrated with Thanos :) (https://github.com/timescale/promscale/pull/664)