A simple empty main with evented-io would not quit, because some threads were still waiting to be resumed (by the os). The os.write to the eventfd only wakes up one thread and thus there are multiple writes needed to wake up all the other threads.
A simple empty main with evented-io would not quit, because some threads were still waiting to be resumed (by the os). The os.write to the eventfd only wakes up one thread and thus there are multiple writes needed to wake up all the other threads.