[ROS2]Is it possible to have callbacks on different threads in one node?

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Hello mates,

I am having a node with both service and subscriber. While the service call executes an external controller for quite a long time, it blocks the callback for the subscriber. Is there any way that the callback function for the subscriber could be run on a different thread so that both callbacks function simultaneously?

FYI, previously I tried to run a separate node for the subscriber but my controller needs the real-time update of data from the subscriber callback. A separate subscriber node forced me to pass the data class two times, which is troublesome when I need to modify some codes later.