[fangjin]

The databases listed above, to the best of my knowledge, are commonly used for dev ops metrics data and share similar terminology. Druid on the other hand, draws much of its terminology from the OLAP world. As cheddar clarified in his post above, the benchmarks for Druid are misleading as it is not an apples to apples comparison (I suspect the benchmarks for ES also suffer from this problem). A single Druid event may consist of thousands of metrics.