Solution : https://service.sap.com/sap/support/notes/1527505 (SAP Service marketplace login required)
Key words :
Oracle 11.2.0.2 , underscore parameter , patch collection , unix _first_spare_parameter, _mutex_wait_scheme, _mutex_wait_time
Related Notes :
| 1588876 | Oracle Enhancement to add different "Mutex" wait schemes |
| 1431798 | Oracle 11.2.0: Database Parameter Settings |