Cache Effects of Virtual Machine Placement on Multi-Core Processors

Virtual machine prevalence in datacenters introduces a range of potential efficiency issues. It is well known that virtual machines negatively impact application performance when compared to native execution. Multi-core architectures present new opportunities for limiting the performance impact of virtualized execution. The research presented in this paper examines the effects of multi-core cache structure on scientific applications running inside Xen virtual machines. Multiple strategies for assigning virtual machines to physical CPUs are detailed for cases where one or more virtual machines reside on a single node. The results show that placing virtual machines in caches generally improves performance when compared to the default scheduling scheme.