That one is easy, having worked with space-constrained data collection myself (not personal data, it's sensor data so no ethical concerns). You do a "pre-summa

That one is easy, having worked with space-constrained data collection myself (not personal data, it's sensor data so no ethical concerns). You do a "pre-summarization" of the data on the client side, and just send a report to the mothership. Consequence of this is that it will result in using CPU resources of the client - and that explains why the telemetry service eats so much of it on Windows.