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PI71145: CHANGE DEFAULT NUMBER OF IC SUBTASKS

A fix is available

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APAR status

  • Closed as new function.

Error description

  • Change default number of sub tasks that works in parallel.
    Current default number is 253, but it is not realistic number to
     run in parallel. The customer should set fewer number of tasks
    in TASKCTL.
    IMS HP Image Copy change the default value of task number that
    can work most of running environment.
    

Local fix

  • N/A
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED: All IMS High Performance Image Copy for z/OS *
    *                 Version 4 Release 2 users ( FMID=H1J0420 )   *
    ****************************************************************
    * PROBLEM DESCRIPTION: >>>>> ATTENTION >>>>>  ATTENTION >>>>>  *
    *                      After applying this maintenance, the    *
    *                      default number of tasks in parallel is  *
    *                      changed to 15. If you process more      *
    *                      than 15 DBDSs or areas by AIC or ACIC   *
    *                      in a step with using default number of  *
    *                      tasks, the performance of image copy    *
    *                      process may be decreased.               *
    *                                                              *
    *                      You consider to set larger numbers      *
    *                      by IMS HP Image Copy keywords for       *
    *                      tasks in the GLOBAL statement or IMS    *
    *                      HP Image Copy site default table for    *
    *                      improving the performance.              *
    *                      <<<<< ATTENTION <<<<< ATTENTION <<<<<   *
    *                                                              *
    *                      IMS HP Image Copy changes the default   *
    *                      value of keywords as follows:           *
    *                      - TASKCTL=(15,5)                        *
    *                      - GRPLIM=(15,5)                         *
    *                      - SHDWTCTL=15                           *
    *                                                              *
    *                      These keywords control the number of    *
    *                      processing tasks in parallel for        *
    *                      creating image copy data sets, Offload  *
    *                      copy process, or creating shadow data   *
    *                      sets.                                   *
    *                                                              *
    *                      Additionally, this APAR fixes the       *
    *                      potential problem of IMS HP Image Copy  *
    *                      that the process of HASH Check of IMS   *
    *                      HP Pointer Checker is canceled with     *
    *                      message FABP2124E ( MSGFABP2124E )      *
    *                      and Image Copy function terminates      *
    *                      with RC=08.                             *
    *                                                              *
    *                      It occurs when all of the following     *
    *                      conditions are satisfied:               *
    *                      - Copy process of Advanced Image Copy   *
    *                        Services is used.                     *
    *                      - HASH Check option for the full        *
    *                        function database is applied          *
    *                        (HDPC=Y).                             *
    *                      - The requested number of tasks for     *
    *                        the pointer checker or creating       *
    *                        secondary image copy is larger than   *
    *                        the maximum number of tasks for       *
    *                        creating primary image copy process.  *
    ****************************************************************
    * RECOMMENDATION: Apply the maintenance for this APAR.         *
    ****************************************************************
    >>>>>>>>>> ATTENTION >>>>>  ATTENTION >>>>> ATTENTION >>>>>>>>>>
    
    After applying this maintenance, the  default number of tasks
    in parallel is   changed to 15. If you process more than 15
    DBDSs or areas by AIC or ACIC    in a step with using default
    number of tasks, the performance of image copy process may be
    decreased.
    
    You consider to set larger numbers  by IMS HP Image Copy
    keywords for   tasks in the GLOBAL statement or IMS HP Image
    Copy site default table for   improving the performance.
    <<<<<<<<<< ATTENTION <<<<< ATTENTION <<<<< ATTENTION <<<<<<<<<<
    
    
    IMS HP Image Copy changes the default value of keywords as
    follows:
    - TASKCTL=(15,5)
    - GRPLIM=(15,5)
    - SHDWTCTL=15
    These keywords control the number of processing tasks in
    parallel for creating image copy data sets, Offload copy
    process, or creating shadow data sets.
    By this APAR, IMS HP Image Copy changes the default value of
    task number that can work most of running environment.
    
    Additionally, this APAR fixes the potential problem of IMS HP
    Image Copy that the process of HASH Check of IMS HP Pointer
    Checker is canceled with message FABP2124E ( MSGFABP2124E ) and
    Image Copy function terminates with RC=08.
    
    It occurs when all of the following conditions are satisfied:
    - Copy process of Advanced Image Copy Services is used.
    - HASH Check option for the full function database is applied
      (HDPC=Y).
    - The requested number of tasks for the pointer checker or
      creating secondary image copy is larger than the maximum
      number of tasks for creating primary image copy process.
    
    When IMS HP Pointer Checker is scheduled for HASH Check process
    in the Image Copy function, IMS HP Image Copy notifies the
    allowable number of tasks in parallel that invoke HASH Check at
    the same point in time. In the COPY process of Advanced Image
    Copy Services, its number is equivalent to the number of
    Offload tasks that is specified as second parameter of TASKCTL
    or GRPLIM keyword.
    However, IMS HP Image Copy notifies the allowable number of
    tasks for the primary image copy process in parallel wrongly.
    As a result, IMS HP Pointer Checker determines that a failure
    occurred in IMS HP Image Copy and cancels HASH Check function
    because the number of Offload copy tasks exceeds the maximum
    number of tasks which IMS HP Pointer Checker has.
    

Problem conclusion

Temporary fix

Comments

  • IMS HP Image Copy changes the default value of keywords for
    controlling the number of tasks in parallel.
    
    IMS HP Image Copy notifies the maximum number of Offload copy
    tasks to IMS HP Pointer Checker which is called in the Offload
    copy tasks.
    
    
    ========================
    = DOCUMENTATION CHANGE =
    ========================
    IMS High Performance Image Copy for z/OS Version 4 Release 2
    User's Guide SC19-2756-01 ( SC19275601 ) should be changed as
    follows:
    
    Running IMS HP Image Copy
      Control statements and keywords
        ICEIN control statement keywords
    
          GRPLIM keyword
            Format
    
    |                  +-(15,5)--------+
              GRPLIM= -+-nnn-----------+-------------><
                       +-(+-----+-,mm)-+
                          +-nnn-+
    
                nnn The left-aligned maximum number of tasks in
                    the GROUP. Valid value is 0 - 253. When the
                    specified value is 0, it means
    |               GRPLIM=253. The default value is 15.
    
                mm  The left-aligned maximum number of tasks in
                    the GROUP for the Offload Copy process.
                    Valid value is 0 - 64. When the specified
                    value is 0, it means GRPLIM=(,64). The default
    |               value is 5. it means GRPLIM=(,64). The default
                    value is 5.
            Default value
    |         GRPLIM=(15,5)
              GRPLIM=(15,5)
          SHDWTCTL keyword
            Format keyword
    |                    +-15-+
              SHDWTCTL= -+-nn-+--------><
              SHDWTCTL= -+-nn-+--------><
                nn The maximum number of shadow data set creation
                   subtasks that can run in parallel. The validon
                   value of nn is in the range of 0 - 64. valid
    |              When the specified value is 0, it means
    |              SHDWTCTL=64. The default value is 15.ns
                   SHDWTCTL=64. The default value is 15.
            Default value
    |         SHDWTCTL=15
              SHDWTCTL=15
            Usage value
    |         Shadow data set is created by Advanced Image Copy
    |         Services. You might need toby Advanced Image Copy
              adjust appropriate SHDWTCTL= value in your system
              environment not to exceed its capacity.our system
              environment not to exceed its capacity.
          TASKCTL keyword
            Formatkeyword
            Format
    |                   +-(15,5)--------+
              TASKCTL= -+-nnn-----------+--------><
                        +-(+-----+-,mm)-+--------><
                           +-nnn-+-,mm)-+
                           +-nnn-+
                nnn The maximum number of IC subtasks that can run
                    in parallel.
    
                    The value must be in the range of 0 - 253. When
                    the specified value is 0, it means TASKCTL=253.
    |               The default value is 15.
    
                    When the specified DBDS is a HALDB and the
                    database is flagged as ONLINE REORG CAPABLE in
                    DBRC, IMS HP Image Copy automatically
                    determines the ACTIVE DBDS and uses the active
                    DBDS ddname as its input.
    
                mm  The maximum number of Offload Copy subtasks that
                    can run in parallel. The value must be in the
                    range of 0 - 64. When the specified value is 0,
    |               it means TASKCTL=(,64). The default value is 5.
    
            Default value
    |         TASKCTL=(15,5)
    

APAR Information

  • APAR number

    PI71145

  • Reported component name

    IMS HP IMAGE CO

  • Reported component ID

    5655K9600

  • Reported release

    420

  • Status

    CLOSED UR1

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    YesSpecatt / New Function / Xsystem

  • Submitted date

    2016-10-24

  • Closed date

    2016-11-10

  • Last modified date

    2016-12-01

  • APAR is sysrouted FROM one or more of the following:

  • APAR is sysrouted TO one or more of the following:

    UI42494

Modules/Macros

  • FABJGLRP FABJMAIN FABJOFDD FABJPARM FABJPRM2
    FABJTGEN
    

Publications Referenced
SC19275602    

Fix information

  • Fixed component name

    IMS HP IMAGE CO

  • Fixed component ID

    5655K9600

Applicable component levels

  • R420 PSY UI42494

       UP16/11/15 P F611

Fix is available

  • Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.

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Document Information

Modified date:
14 December 2020