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InfluxDB
Power Real-Time Data Analytics at Scale. Get real-time insights from all types of time series data with InfluxDB. Ingest, query, and analyze billions of data points in real-time with unbounded cardinality.
You might also want to look into LK ("little kernel"). It's the basis for both the Android and WebOS bootloaders, which I've also worked on. It has multi-threading and I/O but doesn't support user processes. Might be good for embedded systems.
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