An apparatus and method for transferring data in a data processing system to and from a host system (11). A communication adapter (10) or input/output controller device is provided in which queues (36) are utilized to transfer information between the adapter or controller and the host system (11). In order to minimize the amount of time a system or I/O bus or network is used during transfer of data between the adapter or controller and the host system, and reduce the amount of work that must be performed by the host system (11), the number of interrupts by the adapter (10) or controller of the host system is limited to the minimum amount necessary by using an interrupt arm mechanism (44) and by keeping track of completion indices stored in the host system.