1. A method of estimating performance of a design, the method comprising: selecting a segment of the design comprising a plurality of segments for hardware emulation; wherein the design is specified using processor-executable instructions; and modifying the design, using a processor of a host system, to invoke a generic accelerator of an emulation system in lieu of executing the selected segment within a processor of the emulation system; wherein at least one other segment of the plurality of segments executes in the processor of the emulation system; implementing the emulation system within an integrated circuit; and programming the generic accelerator to mimic behavior of the selected segment and generate a data traffic pattern corresponding to the selected segment without performing an exact function of the selected segment.