SpaceX software engineers answered questions on Reddit.

Each launch of 60 satellites contains more than 4,000 Linux computers. The Starlink constellation has more than 30,000 Linux nodes (and more than 6,000 microcontrollers) in space right now. Starlink shares its Linux platform infrastructure with Falcon and Dragon. Starlink get the benefit of our more than 180 vehicle-years of on-orbit test time.

The system is generating over 5 terabytes per day of diagnostic data.