1. A system comprising: a plurality of execution units configured to execute, at least in part, a plurality of instruction threads; a plurality of performance monitors, each performance monitor being configured to collect performance information related to the execution of at least one instruction thread; a selected thread identifier configured to provide, during operation, the selection of at least one instruction thread; and a performance manager configured to instruct the performance monitors to collect performance information when the selected instruction thread is being executed, and not when a non-selected instruction thread is executed.