This will make the library more robust in business usage.
Thread pool thread could be blocked (though it is bad design, but still inevitable). In case of blocked thread accumulate for some reason, the thread pool won't have a free thread to handle a callback, which will cause radical problems at user code.
A better designed thread pool is like .Net thread pool, which will grow once it detect a thread is blocked for a long time (seconds), and shrink in another strategy.
Thread pool thread could be blocked (though it is bad design, but still inevitable). In case of blocked thread accumulate for some reason, the thread pool won't have a free thread to handle a callback, which will cause radical problems at user code.
A better designed thread pool is like .Net thread pool, which will grow once it detect a thread is blocked for a long time (seconds), and shrink in another strategy.