1. A computer program product for optimization of tracks on a hard disk, the computer program product comprising: a non-transitory computer readable storage medium having computer readable program code embodied therewith, the computer readable program code configured to: determine I/O characteristics for a plurality of data clusters to be stored on the hard disk; generate a set of solutions for each possible placement configuration for the plurality of data clusters; for each solution, calculate a cost function value for a plurality of cost functions using the I/O characteristics for the plurality of data clusters; for each solution, calculate a membership value using the cost function values, wherein the membership value represents how good the solution is as part of an optimal placement map; for each solution, calculate a fitness value using the membership value, wherein the fitness value serves as an indication of how fit the solution is as part of the optimal placement map; retain the solutions with the fitness value greater than a predetermined threshold; determine whether at least one stopping condition has been met; in response to determining that none of the stopping conditions have been met, add new solutions to the retained solutions to generate the next set of solutions; and repeat the calculating of the membership value using the cost function values, the calculating of the fitness value using the membership value, and the retaining of the solutions with the fitness value greater than the predetermined threshold until at least one stopping condition has been met.