A multiprocessing system is disclosed. The system includes a multithreading microprocessor, including a plurality of thread contexts (TCs), each comprising a first control indicator for controlling whether the TC is exempt from servicing interrupt requests to an exception domain for the plurality of TCs, and a virtual processing element (VPE), comprising the exception domain, configured to receive the interrupt requests, wherein the interrupt requests are non-specific to the plurality of TCs, wherein the VPE is configured to select a non-exempt one of the plurality of TCs to service each of the interrupt requests, the VPE further comprising a second control indicator for controlling whether the VPE is enabled to select one of the plurality of TCs to service the interrupt requests. The system also includes a multiprocessor operating system (OS), configured to initially set the second control indicator to enable the VPE to service the interrupts, and further configured to schedule execution of threads on the plurality of TCs, wherein each of the threads is configured to individually disable itself from servicing the interrupts by setting the first control indicator, rather than by clearing the second control indicator.