MQTT receiver crashes on big spread counts for 'Topic'

Hi everybody, hi @korriander,

i have tested the MQTT node contained in NODE15’s workshop material ‘Internet of Things’:

Therefore i set up the following scenario:

  • 2 VVVV-MQTT clients in a local network (i use 1 as sender and 1 as receiver)
  • A local broker (server) with default configuration running on one of those computers

Once i subscribe to ~100 topics and send continuous changing data for all of those topics, MQTT receiver (network) sometimes shows up red in some frames. TTY then says:

00:00:33 ERR : Exception occured in TMPluginWrapperNode.Evaluate
00:00:33 ERR : Die Warteschlange ist leer.

When subscribing to even more topics (~175) vvvv crashes immediately when data for all those topics is received.

This scenario is 100% reproducable in my setup.

Seems as if the MQTT receiver node would not be tweaked for high peformance with big spreadcounts? (while MQTT itself is probably not designed for such a real-time scenario, too?)


Thanks for the info.
While MQTT definitely is no Protocol for realtime high speed Data Transmission, 170 topics should not be an issue.

Hope I will find time soon to have a look into it …