//we must guarantee these objects not be freed from the heap or reused, so we move these objects from object_can to invalid_object_can, and free them
//we must guarantee these objects not be freed from the heap or reused, so we move these objects from object_can to invalid_object_can, and free them
//from the heap or reuse them in the near future. if ASCS_CLEAR_OBJECT_INTERVAL been defined, clear_obsoleted_object() will be invoked automatically and
//from the heap or reuse them in the near future. if ASCS_CLEAR_OBJECT_INTERVAL been defined, clear_obsoleted_object() will be invoked automatically and
//periodically to move all invalid objects into invalid_object_can.
//periodically to move all invalid objects into invalid_object_can.