Tasks are assigned to processors of a system. The resident set size of each task is determined, specifying the amount of physical information allocated thereto, and locational information of this memory with respect to the processors is determined. Each task is assigned one processor, based on the task's resident set size, and the locational information of the task's allocated physical memory. Each task is attempted to be assigned to the processor closest to the largest portion of the physical memory allocated thereto. A number of the tasks may be determined as best suited to run on a given processor, but the given processor may be unable to run them all. The processor may be thus assigned only those tasks that have a greatest amount of physical memory allocated that is closest to the processor, such as the greatest amount or percentage of physical memory allocated that is local to the processor.