Combining Virtual Machine migration with process migration for HPC on multi-clusters and Grids

The renewed interest in virtualization gives rise to new opportunities for running high performance computing (HPC) applications on clusters and grids. These include the ability to create a uniform (virtual) run-time environment on top of a multitude of hardware and software platforms, and the possibility for dynamic resource allocation towards the improvement of process performance, e.g., by virtual machine (VM) migration as a means for load-balancing. This paper deals with issues related to running HPC applications on multi-clusters and grids using VMware, a virtualization package running on Windows, Linux and OS X. The paper presents the ldquoJobrunrdquo system for transparent, on-demand VM launching upon job submission, and its integration with the MOSIX cluster and grid management system. We present a novel approach to job migration, combining VM migration with process migration using Jobrun, by which it is possible to migrate groups of processes and parallel jobs among different clusters in a multi-cluster or in a grid. We use four real HPC applications to evaluate the overheads of VMware (both on Linux and Windows), the MOSIX cluster extensions and their combination, and present detailed measurements of the performance of Jobrun.