Patent ID: 8230069

Claim:
A method of selecting a target physical machine for a virtual machine (VM) migration, comprising: determining one or more candidate physical machines with sufficient spare capacity to host the VM by dynamically: monitoring status of each VM and each physical machine at a storage subsystem level, wherein dynamically monitoring status of VMs comprises continuously measuring CPU, memory and network bandwidth resources used by each VM over time to estimate ongoing needs of each VM for CPU, memory and network bandwidth resources, and wherein dynamically monitoring status of each physical machine results in providing measurements for a send and receive packet rate for each fiber channel port on each switch in the SAN; gathering statistics and measurements for obtaining estimates for storage data transfer bandwidth and storage command throughput between the VM and associated storage volume in a storage area network (SAN), wherein the estimates are translated to capacity requirements on paths from host to storage volumes for each VM; preferentially selecting as VM migration targets among the candidate physical machines one or more physical machines with sufficient storage volume connectivity and spare path capacity to satisfy storage volume access requirements of the VM, to host the VM, wherein VMs and physical machines are ranked, each VM and each candidate physical machine are paired based on the ranking, and VMs are selected for migration to a new assigned physical machine based on ranking values; and continuously migrating VMs to selected candidate physical machines until sufficient migrations are performed to offload all overloaded physical machines so that load on all overloaded physical machines are reduced below a predetermined utilization threshold, wherein migrating VMs to selected candidate physical machines includes migration away from a source physical machine to the selected candidate physical machines.