rough-minister-5825604/06/2016, 1:11 AM
When using Pool.apply, the task (function) is sent to the task queue, which is consumed by the worker. At this point the task is "in progress". However, the worker dies without being able to finish the task or in any other way tell the Pool that it can't finish the task. The actual process is then ended by the Pool but the task is still in limbo, so any attempt at getting a result will hang forever.