A computer program product and apparatus for reallocating memory in a logically partitioned environment. The invention comprises a Performance Enhancement Program (PEP) and a Reallocation Program (RP). The PEP allows an administrator to designate several parameters and identify donor and recipient candidates. The RP compiles the performance data for the memory and calculates a composite parameter. For each memory block in the donor candidate pool, the RP compares the composite parameter to the donor load threshold to determine if the memory is a donor. For each memory block in the recipient candidate pool, the RP compares the composite parameter to the recipient load threshold to determine if the memory is a recipient. The RP calculates the recipient workload ratio and allocates the memory from the donors to the recipients. The RP monitors and update the workload statistics based on either a moving window or a discrete window sampling system.