Methods and apparatuses for bounding the processing domain in a symmetric multiprocessing system are provided. In various implementations, a particular computational task is “affined” to a particular processing unit. Subsequently, when the particular task is executed, the symmetric multiprocessing operating system ensures that the affined processing unit processes the instruction. When the affined processing unit is not processing the particular computational task, the symmetric multiprocessing operating system may cause the processing unit to process alternate instructions. With some implementations, a particular computational task is “linked” to a particular processing unit. Subsequently, when the particular task is executed, the symmetric multiprocessing operating system ensures that the bound processing unit processes the instruction. When the bound processing unit is not processing the particular computational instruction, the bound processing unit may enter a low power or idle state.