A framework for routing and resource allocation in network virtualization

Computer architectures for high performance computing have traditionally been based on an assumption of one parallel application running alone on one machine. The current trend is, however, that huge computer installations offer compute power to a set of users or customers, each demanding only a subset of the available compute resources. This places new requirements on the architecture, in that it must support dynamic partitioning of the resources into several virtual servers as demand changes. We introduce a novel framework which supports flexible formation of such virtual servers while preventing interference between the communication of different virtual servers. This paper investigates the impacts of a shared interconnection network on applications running on virtual compute servers. We show that the interconnect performance supplied to each job is highly unpredictable, and that a job can experience a performance degradation of 97% when its traffic interferes with the traffic of concurrent jobs. With a minor reduction in the utilization of each processing node, this can be considerably improved through a combination of routing-containment in the interconnection network and a carefully designed resource allocation strategy.