A time series database is anything that stores data with time attached, so log storage does count.
The more pertinent difference is event logging vs. metrics.
For the former the ELK stack is popular, and Prometheus.io is suitable for the latter.
The more pertinent difference is event logging vs. metrics.
For the former the ELK stack is popular, and Prometheus.io is suitable for the latter.
I found that by trying to see if it could be used as a metrics DB but stumbled upon a few issues like configuring retention times per target. See for example https://github.com/prometheus/prometheus/issues/1381
Prometheus has lots of potential but it's not a metrics DB at this point or in the near future. I just wish they'd made that a bit clearer on the page.
"We make design decisions that presume that Promtheus data is ephemeral, and can be lost/blown away with no impact."
That viewpoint pretty much limits them to be an ops tool. I wish they'd reconsider this point.