taskA                                                                     
                                                                                                              
                                                                               dataaaa                        
                                                                                                              
                                                                                                              
                   OK                                                                                     NG  
                                                   check                                                      
                                                                                                              
                                                                                                              
                                                                                                              
                                                                                                              
                                                                                                              
                                                                                                              
                                                                                                          true
                                              retry?                                                          
                                                                               false