Embodiments of the present invention address deficiencies of the art in respect to threading model switching between asynchronous I/O and synchronous I/O models and provide a novel and non-obvious method, system and computer program product for autonomic threading model switching based upon I/O request types. In one embodiment, a method for autonomic threading model switching based upon I/O request types can be provided. The method can include selectably activating and de-activating a blocking I/O threading model according to a volume of received and completed blocking I/O requests.