11.17 IBM i Authority Checking

IBM i authority checking can impact system performance. The IBM i performance reports have a section that lists "exceptions".

In this list are "security" or "authority" exceptions. The rate at which these exceptions occur and impact system performance is shown in the following figure:

 

     Authority Exceptions   Percentage of Total CPU Cycles consumed

     Rate per Second            B10  B20  B30  B40  B50  B60  B70

          10                     6    3    5    3    2    1    1

          25                    15    9   12    8    5    3    2

          50                    29   17   25   16   10    6    4

         100                    58   34   49   32   20   12    9

         200                         69   99   63   39   24   17

         300                                   95   59   36   27

         400                                        78   48   35

         500                                        98   60   44

         600                                             71   53

         700                                             83   62

         800                                             95   71

         900                                                  80

        1000                                                  89

 

If high exception rates are found, steps can be taken to alter IBM i security settings to reduce the number of exceptions that are occurring.