A computing system includes a multi-core processor and a core controller. The core controller is for: monitoring utilization of the multi-core processor; calculating a target performance index according to the utilization of the multi-core processor, a target utilization and a first performance index, wherein the first performance index is associated with a first entry of a dynamic voltage frequency scaling (DVFS) table that corresponds to a current setting for the multi-core processor; and selecting a second entry of the DVFS table that corresponds to a target-setting according to the target performance index and a second performance index that is associated with the second entry. The target-setting is used to configure the multi-core processor.