Methods and apparatus, including computer program products, for identifying unnecessary synchronization objects in software applications. A computer-implemented method for determining a usefulness of synchronization objects includes, in a multi-threaded application program, tracking threads as they are created and terminated, intercepting application program interfaces (APIs) used to create and destroy thread synchronization objects, in the API wrappers, tracking existing synchronization objects in a list, and associating a list entry for each of the synchronization objects with a unique bit in a bit field.