Optimization of computer system logical partition migrations in a multiple computer system environment

Workload, preferably as one or more partitions, is migrated from a source server to one or more target servers by computing a respective projected performance optimization for each candidate partition and target, the optimization being dependent on a projected processor-memory affinity resulting from migrating candidate workload to the candidate target, and selecting a target to receive a workload accordingly. A target may be pre-configured to receive a workload being migrated to it by altering the configuration parameters of at least one workload currently executing on the target according to the projected performance optimization.