MQTT Performance Tests: Encryption

Point-to-Point over TLS 1.3

The point-to-point test with every client connected over TLS 1.3: 25,000 publishers, 25,000 subscribers, each pair on its own topic, QoS 1, a 16-byte payload, ten minutes per rate. Every broker runs at 50K messages a second; 75K and 100K only those whose median latency stayed under 100 ms at the rate before.

Mosquitto and EMQX are in the 50K table and in neither of the other two. Both ran at 50K and both came in over the limit that gates the higher rates - EMQX at a 2.9-second median, Mosquitto at 152.9 seconds, twenty-nine times and fifteen hundred times the 100 ms allowed. Carrying either forward would have measured how long a queue takes to drain rather than how fast a broker delivers, so the 75K and 100K tables compare the three brokers that stayed in the microsecond range: XMQ, FlashMQ and HiveMQ.

Encryption costs one TLS record and one system call per message, on both sides. The memory column shows the other cost: the TLS state of 50,000 connections.

EMQX did not answer CONNECT for 17 of its 25,000 publishers and 10 of its 25,000 subscribers within 60 seconds at 50K; those clients were left out of its run.