A method utilizes event-driven reoptimization to reallocate one or more logical partitions within a pool of logically-partitioned data processing systems in a logically-partitioned computing environment in response to detection of a system event that is likely to increase or decrease the collective resource demands of logical partitions resident in a logically-partitioned computing environment. The reoptimization may be used to consolidate logical partitions on fewer processor nodes to improve the potential for powering down hardware resources and thereby reduce power consumption.