SQL> @tune_spin_count

SPIN_COUNT                                                                      
----------                                                                      
2000                                                                            

SPIN HIT RATE  SPIN COST                                                        
------------- ----------                                                        
       93.53%          6                                                        

Enter new _spin_count value to try: 4000
Enter time to wait (in seconds): 900

SPIN HIT RATE  SPIN COST                                                        
------------- ----------                                                        
       96.27%          4                                                        

SQL>