This is the direction that QuestDB (www.questdb.io) has taken: columnar database, partitions by time and open source (apache 2.0). It is written is zero-GC java and c++, leveraging SIMD instructions. The live demo has been shown to HN recently, with sub second queries for 1.6 billion rows: https://news.ycombinator.com/item?id=23616878
NB: I am a co-founder of questdb.
BTW, VictoriaMetrics  is a time series database built on top of ClickHouse architecture ideas , so it inherits high performance and scalability from ClickHouse, while providing simpler configuration and operation for typical production time series workloads.