I thought I had seen some discussion about this but I didn't find any with a "solved" status. I have several devices some z-wave some zigbee that seem to flood my logs with multiple entries for what I believe should be a single event.
Usually, this just results in the logging entries if it's a motion event, but I've noticed that it sometimes results in multiple executions of rules that are contact sensor triggered. All drivers for the devices are "system" not "user", so this may be some kind of logging or device firmware glitch but since it sometimes results in multiple triggers it seems like it may be an issue with the overall performance of HE?
This an example of the output from a dome dmms1 z-wave sensor logging: