RavenDB - they recently switched to a new engine and did some time series related work. Send them an email and you'll probably get a few free licenses. It's a v

RavenDB - they recently switched to a new engine and did some time series related work. Send them an email and you'll probably get a few free licenses. It's a very well selling commercial product, so the risk of deprecation minimal. I have personally seen millions of records saved per minute on a top end SSD server.