A key performance indicator (KPI) is a value which can be associated with a solution which represents an interesting measure of some aspect of the solution.

For example, in a scheduling problem one may wish to minimize the makespan (date at which all tasks are completed), but other values may be of interest, like the average job completion time, or the maximum number of tasks executing in parallel over the horizon. One can identify such expressions in the model by marking them as KPIs. KPI values are automatically displayed in the log, can be queried after the solve or for each solution, and are exported to a CPO file when the model is exported.

This method adds the given KPI (expression) under the given name to the CP Optimizer engine.