Well hopefully @thomasgubler gave you a good starting point. If more people start using the C++ wrappers we can reduce a lot of boiler plate code and reduce the required programming memory quite a bit. I am not sure of the guts of the uORB topic rate limiting, but I assume if you set the arming topic update rate limit to 0 for instance then you are wasting some cycles getting new information into your sub that you don't really care about.