Add version 2.1.1 for the time being, until 2.2.0 is out
OpenTSDB is a distributed, scalable Time Series Database (TSDB) written on top of HBase. OpenTSDB was written to address a common need: store, index and serve metrics collected from computer systems (network gear, operating systems, applications) at a large scale, and make this data easily accessible and graphable. Thanks to HBase's scalability, OpenTSDB allows you to collect thousands of metrics from tens of thousands of hosts and applications, at a high rate (every few seconds). OpenTSDB will never delete or downsample data and can easily store hundreds of billions of data points. OpenTSDB is free software and is available under both LGPLv2.1+ and GPLv3+. Find more about OpenTSDB at http://opentsdb.net WWW: http://www.opentsdb.net