1. A method for use by a hypervisor operating in a computer system which comprises a plurality of partitions operating on a plurality of logical processors, the method comprising: monitoring utilization levels of the plurality of partitions; determining that a subset of the plurality of partitions are idle based on the utilization level of the subset of the plurality of partitions being below a threshold; monitoring utilization levels of the plurality of logical processors; determining that a subset of logical processors of the plurality of the logical processors are idle based on the monitored utilization level of the subset of the plurality of logical processors being below an idle logical processor threshold percentage; scheduling partitions of the subset of idle partitions on at least one of the logical processors in the subset of idle logical processors.