A method and a system is disclosed for managing distribution of computer-executable program threads between a plurality of central processing units (CPUs) administered by an operating system in a multi-CPU computer system having a plurality of memory caches shared amongst the CPUs. The method includes assigning the CPUs to a plurality of CPU-groups of a predetermined group-size, selecting a CPU-group form the CPU-groups, setting a predetermined threshold for the selected CPU-group, and affinitizing a program thread to the selected CPU-group based on the predetermined threshold wherein the operating system distributes the program threads among the CPU-groups based on the affinitizing. In this way, the memory access time delays associated with the transfer of data amongst the CPU-groups can be advantageously reduced while the ability to more effectively utilize the total number of available CPUs in the processing of the program threads is advantageously increased.