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Erlang / Erlang Advanced Interview questions

How does erlang:send/3 with the nosuspend option change message-sending behavior?

A plain Pid ! Msg send can, in rare cases, briefly suspend the sending process if the underlying distribution buffer to a remote node is full — effectively creating unwanted back-pressure on the sender. erlang:send(Pid, Msg, [nosuspend]) asks for the same send but refuses to suspend the caller: if it would have had to block, it instead returns nosuspend immediately and the message is not delivered.

case erlang:send(Pid, {event, Data}, [nosuspend]) of
    ok -> ok;
    nosuspend -> log_dropped_event(Data)
end.

This is useful for genuinely best-effort traffic — metrics, non-critical notifications — where a sender would rather drop a message than risk stalling itself waiting on a slow or overloaded remote link. It's deliberately not the default, since silently dropping messages is the wrong tradeoff for anything the receiver actually needs to see.

What does erlang:send/3 with [nosuspend] do if the send would normally block?
What kind of traffic is nosuspend best suited for?

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