1. A computer-implemented method of determining system configurations, comprising: under the control of one or more computer systems configured with executable instructions, determining a set of configurations for a system; measuring performance of the system for members of the determined set of configurations; creating, based at least in part on the measured performance, a model of the system; generating, based at least in part on the model, one or more configurations; and providing the generated one or more configurations for tuning the system.