Embodiments of input/output hub unit are disclosed for aggregating interrupts received from multiple endpoint devices. The input/output hub may include an interface unit and one or more communication units. Each communication unit may be configured to receive messages from a corresponding endpoint device. The interface unit may be configured to update a first pointer within a first data structure responsive to a request from a given one of the communication units. The interface unit may be further configured to stored data in a second data structure responsive to updating the first pointer, reading a second pointer and the first pointer, and sending an interrupt responsive to a determination that the first and second pointers are equal.