A system and method for scheduling optical proximity correction (OPC) or other resolution enhancement technique (RET) operations on a layout design is disclosed. A layout design is divided into a plurality of regions, such as a plurality of tiles. OPC is performed on the plurality of tiles in order to generate a modified layout design. Performing OPC on the plurality of tiles may be time consuming. In order to more efficiently distribute the processing of OPC, estimates of OPC processing times for the plurality of tiles is performed. The estimate of the OPC processing time for a respective tile may be based on one or both of analysis of: analysis of the respective tile; or analysis of tile(s) that neighbor the respective tile. Based on the estimates, tiles that have a longer estimated processing tile are scheduled before tiles that have a shorter estimated processing time, thereby potentially resulting in more efficient OPC processing.