Answers to the question you searched for, with the numbers attached.
-
Note
Moving 14,000 screens to MQTT without losing one
Device presence and telemetry moved from HTTP to MQTT on a fleet of about 14,000 screens. A year-long project, four months of tests and a slow rollout, because the worst case was losing contact with screens in the field. Telemetry messages dropped 67%.
measured ▸ telemetry on Kafka: ~42M messages/day before, 13.9M after (−67%) · 13,835 screens reporting
-
Deep dive
Billing-grade telemetry from 15,000 devices
Every ad play is billing evidence, and the screens lose the network for hours. How the proof-of-play pipeline works: cache on the device, batch uploads, sort before insert, a weekly-partitioned MySQL with 2 billion rows, then Kafka and ClickHouse.
measured ▸ ~200 million play rows a day · importer runs of 155k to 643k rows in 7 to 20 s · MySQL era: 2B+ rows, weekly partitions