multi-threaded rospy.get_param() crashes: CannotSendRequest and ResponseNotReady

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Hi all,

I work with the sushi repository from the ICRA Mobile Manipulation Challenge. When instantiating the ArmMover I get "CannotSendRequest" and "ResponseNotReady" exceptions. The ArmMover class creates multiple ArmMoverWorker, which run their own threads. The reason for the crash seems to be requests to the parameter server from multiple threads.

Can the parameter server process multiple requests from different threads running on the same node?

As a workaround I moved the parameter requests into the constructor of the ArmMoverWorker (before the thread is started) and then it works fine.