A method in a data processing system is provided for processing a service request of a client partition. The method includes: obtaining by a service partition of the data processing system the service request from the client partition, wherein both the client and service partitions execute above a hypervisor of the data processing system; and processing the service request by the service partition utilizing a processor quantum assigned to the client partition and donated by the client partition to the service partition. The client partition controls scheduling of the service partition by queuing the service request at the client partition until the client partition decides to proceed with execution of the service request by the service partition. In one implementation, the service partition is a partition adjunct of the data processing system, which utilizes donated virtual address space of the client partition.