I've been pretty happy with OpenTSDB (a TSD built on top of HBase). It happily ingests tens of thousands of points per second, supports full-resolution historic

I've been pretty happy with OpenTSDB (a TSD built on top of HBase). It happily ingests tens of thousands of points per second, supports full-resolution historical data, and has reasonably fast queries. The main downside is HBase is operationally complex, but if you've already made the investment there (as we had), it's a great option.