ClickHouse
A fast open-source OLAP database management system
... reliable and fault tolerant. It supports multi-master asynchronous replication with the option of being deployed across multiple datacenters. With all nodes equal, there is no single point of failure. Downtime of a single node or even the whole datacenter won't affect the system's availability. ClickHouse also has exceptional hardware efficiency and a host of other features, including a feature-rich SQL database, vectorized query execution, real-time query processing and data ingestion, and more.