Cooperative Virtual Machine Scheduling on Multi-core Multi-threading Systems — A Feasibility Study

Virtual machines (VMs) and multi-core multi-threading microprocessors (MMMP) are two emerging technologies in software and hardware, respectively, and they are expected to become pervasive on computer systems in the near future. However, the nature of resource sharing on an MMMP introduces contention among VMs which are scheduled onto the cores and the threads that share the processor computation resources and caches. Such contention can lead to performance degradation of individual VMs as well as the overall system throughput, if not carefully managed. This paper proposes to address this problem through cooperative VM scheduling that takes processor input to schedule VMs across processors and cores in a way that minimizes the contention on processor resources and maximizes the total throughput of the VMs. As a first step towards this goal, this paper presents an experiment-based feasibility study for the proposed approach and focuses on the effectiveness of process contention aware VM scheduling. The results confirm that when VMs are scheduled in a way that mitigates their contention on the shared cache, the cache miss rates from the VMs are reduced substantially, and so do the runtimes of the benchmarks.