The MODIFY CATALOG,REPORT,PERFORMANCE command can be used to examine certain events that occur in the catalog address space. These events represent points at which catalog code calls some function outside of the catalog component, such as enqueues, I/O, or allocation. All such events are tracked, except for lock manager requests and GETMAIN/FREEMAIN activity. An example of the output from this command is:

IEC359I CATALOG PERFORMANCE REPORT
*CAS***************************************************
*  Statistics since 12:14:49.61 on  09/29/2004        *
*  -----CATALOG EVENT----   --COUNT--  ---AVERAGE---  *
*  Entries to Catalog            313     23.418  SEC  *
*  BCS ENQ Shr                   291      0.084 MSEC  *
*  BCS ENQ Excl                   20      0.082 MSEC  *
*  BCS DEQ                       352      0.082 MSEC  *
*  VVDS RESERVE CI                14      0.077 MSEC  *
*  VVDS DEQ CI                    14      0.176 MSEC  *
*  VVDS RESERVE Shr               61      0.153 MSEC  *
*  VVDS RESERVE Excl               2      0.099 MSEC  *
*  VVDS DEQ                       63      0.147 MSEC  *
*  SPHERE ENQ Excl                 2      0.054 MSEC  *
*  SPHERE DEQ                      2      0.033 MSEC  *
*  RPL ENQ                         3      0.210 MSEC  *
*  RPL DEQ                         3      0.244 MSEC  *
*  BCS Get                     2,181      1.102 MSEC  *
*  BCS Put                         2     12.836 MSEC  *
*  BCS Erase                       3     34.630 MSEC  *
*  VVDS I/O                       81      9.310 MSEC  *
*  VLF Define Major                1      3.879 MSEC  *
*  VLF Identify                4,596      0.000 MSEC  *
*  RMM Exit                        8      0.005 MSEC  *
*  Tape Exit                       8      0.001 MSEC  *
*  BCS Allocate                    3     13.102 MSEC  *
*  SMF Write                       9      0.197 MSEC  *
*  VVDS Format                     5     23.878 MSEC  *
*  IXLCONN                         2      1.511 MSEC  *
*  MVS Allocate                    2    267.105 MSEC  *
*  Lookup/Pin UCB                  8      0.329 MSEC  *
*  Unpin UCB                       8      0.340 MSEC  *
*  Capture UCB                     3      0.062 MSEC  *
*  Uncapture UCB                   6      0.061 MSEC  *
*  RACROUTE Auth                  47      5.511 MSEC  *
*  RACROUTE Define                 3    537.213 MSEC  *
*  DADSM Allocate SMS              5     15.163  SEC  *
*CAS***************************************************

The following example shows the output of an unqualified MODIFY CATALOG,REPORT command:

IEC359I CATALOG REPORT OUTPUT         
*CAS************************************************************ 
*  CATALOG COMPONENT LEVEL   = HDZ2210                         * 
*  CATALOG ADDRESS SPACE ASN = 0014                            * 
*  SERVICE TASK UPPER LIMIT  =  180                            * 
*  SERVICE TASK LOWER LIMIT  =   60                            * 
*  HIGHEST # SERVICE TASKS   =    7                            * 
*  # ATTACHED SERVICE TASKS  =    7                            * 
*  MAXIMUM # OPEN CATALOGS   = 1,024                           * 
*  ALIAS TABLE AVAILABLE     = YES                             * 
*  ALIAS LEVELS SPECIFIED    = 1                               * 
*  SYS% TO SYS1 CONVERSION   = OFF                             * 
*  CAS MOTHER TASK           = 009AC680                        * 
*  CAS MODIFY TASK           = 009FC7E0                        * 
*  CAS ANALYSIS TASK         = 009FC380                        * 
*  CAS ALLOCATION TASK       = 009FC5B0                        * 
*  CAS ASYNC TASK            = 009FC150                        * 
*  CAS SYSPLEX COMMAND TASK  = 00994C58                        * 
*  CAS SYSPLEX QUIESCE TASK  = 00994E88                        * 
*  VOLCAT HI-LEVEL QUALIFIER = SYS1                            * 
*  NOTIFY EXTENT             =   80%                           * 
*  DEFAULT VVDS SPACE        = ( 10, 10) TRKS                  * 
*  ENABLED FEATURES          = DSNCHECK SYMREC UPDTFAIL        * 
*  DISABLED FEATURES         = DELFORCEWNG VVRCHECK            * 
*  DISABLED FEATURES         = AUTOTUNING BCSCHECK             * 
*  DISABLED FEATURES         = DELRECOVWNG EXTENDEDALIAS       * 
*  DISABLED FEATURES         = ECS AUTOADD DUMPON              * 
*  INTERCEPTS                = (NONE)                          * 
*CAS************************************************************ 

This command can be useful in identifying performance problems that you suspect are related to catalog processing. For example, if the average time for ENQS that is shown in the report seems excessive, it might indicate some problems in the GRS configuration, or parameter specifications. High I/O times might indicate problems:

• With channel or device load
• With volumes that are suffering a high number of I/O errors
• With volumes that have excessively high RESERVE rates or long RESERVE durations.

In the previous example, the last entry identifies an average of over 15 seconds per DADSM allocate request. This might indicate some problem with reserved volumes, or I/O errors.