ZeroMQ
Blocking vs Poll
Block could get stuck here : - Worker thread, as in our example: Ctrl+C goes to the main thread. It does not automatically interrupt the worker’s recv_multipart(), so that worker can remain blocked.
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while running:
frames = socket.recv_multipart() # Wait here until a message arrives
ctrl-C goes to the main thread. So if this is running on the main thread, recv will be interrupted. Otherwise, if this runs on another thread, the worker thread can remain blocked.
With a timeout-based poll:
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while running:
events = dict(poller.poll(100))
if socket in events:
frames = socket.recv_multipart()
Here, If data arrives, wake up immediately. Otherwise, sleep for up to 100 milliseconds, IDLE, then return.
This one is busy polling, which could consume some CPU:
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while running:
events = dict(poller.poll(0)) # Return immediately; loop again
