I thought someone was going to mention http://druid.io/ http://druid.io/. I end up not using it for anything, but at some point I was investigating time series

I thought someone was going to mention http://druid.io/ http://druid.io/. I end up not using it for anything, but at some point I was investigating time series DBs and I thought it was interesting. If I'm not wrong it combines both very fast in-memory OLAP features and what they call "Deep Storage", which I think is a way to store things on disk for slower historical analysis.