Resource allocation in clusters of virtual machines

The problem addressed in this note refers to an important separation constraint that is commonly imposed on the assignment of virtual machines to physical servers. Namely, the requirements of high-availability and security of services, as well as design of database systems, usually specify classes of virtual machines that must be separated, that is, located on separate physical hosts. In the following sections we propose ways of allocating a given set of virtual machines on physical hosts that meet the requirements of separation while optimizing allocation of shared computing resources.