Проприетарная? В опенсорсе? 😁
OpenTSDB's data model is almost identical to Prometheus's: time series are identified by a set of arbitrary key-value pairs (OpenTSDB tags are Prometheus labels). All data for a metric is stored together, limiting the cardinality of metrics. There are minor differences though: Prometheus allows arbitrary characters in label values, while OpenTSDB is more restrictive. OpenTSDB also lacks a full query language, only allowing simple aggregation and math via its API.