Load balance

The degree to which work is evenly distributed among available processors on a multi processor system. A program executes most quickly when it is perfectly load balanced, that is when every processor has a share of the total amount of work to perform so that all processors complete their assigned tasks at the same time. One measure of load imbalance is the ratio of the difference between the finishing times of the first and last processors to complete their portion of the calculation to the time taken by the last processor.