A db that backs lots of time based graphs. They generally hit some pathological cases for general dbs. Frequent write of small data, most recent time is very h

A db that backs lots of time based graphs. They generally hit some pathological cases for general dbs. Frequent write of small data, most recent time is very hot so sharding is tricky, queries generally pull lots of little bits of data in from long time ranges, resolution of past data can often be lowered, etc. Opentsdb for instance was built on top of Hbase because implementing one naively in hbase hits tons of performance issues.