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Initializing BBXS

The BBXS Subsystem is automatically initialized by the first BMC product that needs to use it. There is no requirement to initialize it or even define it in the IEFSSNxx PARMLIB member.  All other address space that make use of the BBXS Subsystem will then use the one created automatically.

If you need to reinitialize the BBXS Subsystem (after applying maintenance or on the recommendation of BMC Support) the BBXSINIT program has been provided. 

BMC ships a sample started task procedure for BBXS initialization in the prefix.BBSAMP data set.

During customization, the @BBXINIT member is copied to a library that you specify and renamed to BBXSINIT. This procedure runs the BBXSINIT program that initializes or reinitializes the BBXS subsystem.

BMC recommends that you use the BBXSINIT procedure early in the IPL process or after applying maintenance to BBXS.


Except in places where the @BBXINIT procedure is specifically mentioned, the remainder of this appendix uses the term BBXSINIT interchangeably to refer to both the program and the procedure that executes the program. After BBXS is initialized, routines and shared data areas loaded into CSA memory remain there until the next IPL.

The BBXSINIT program, as the name implies, creates new copies of the BBXS modules and data areas in CSA and initializes all ongoing BBXS processes, such as channel and device data collection. Any new product startups or product restarts use the new BBXS code and data areas. CSA used by a previous initialization of BBXS is not released until an IPL occurs.

Do not run the BBXSINIT program as part of another startup procedure. If the other procedure needs to run more than once between IPLs, BBXS is reinitialized and claims more valuable CSA space.

Reinitialization of BBXS is required so that changes to CSA-resident BBXS modules become effective and dynamically loaded modules match the version of the CSA-resident modules. The reinitialized version of BBXS works with all versions of BMC products because BBXS is downwardly compatible.


  • BMC recommends that you recycle all products that use BBXS after the BBXS subsystem is reinitialized so that the new BBXS code is used by all applications.

  • The COMMON STORAGE MONITOR component of MainView for z/OS allows the user to collect data on the allocations and use of common storage (CSA). This component can be activated or not activated. BMC recommends starting this monitor as soon as possible in order to track all CSA allocations directly after IPL.

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  1. Feli Brachthaeuser

    Hello, please add a note for PTF BPB1543: The change will take effect the first time (and only the first time) BBX is initialized after an IPL. If you want to make this change effective prior to an IPL it will be necessary to execute the following job: //DEACT EXEC PGM=BBXDCC00,PARM=''DEACT'' //STEPLIB DD DISP=SHR,DSN=????????.BBLINK //* //ACT EXEC PGM=BBXDCC00,PARM=''ACT'' //STEPLIB DD DISP=SHR,DSN=????????.BBLINK Note: The BBX initialization program, BBXSINIT, will NOT activiate this change and therefore its use IS NOT NECESSARY OR RECOMMENDED. Thanks, Feli

    Jul 23, 2018 02:44
    1. Aparna Saxena

      Hi Feli,

      Thank you for your feedback! We've forwarded this information to the writer responsible for this content.

      Regards, Aparna

      Jul 24, 2018 10:31
      1. Dottie Wood

        Hi, Feli. The team looked into the issue and reports that PTF BPB1543 fixes a problem that PTF BPB1517 introduced. As such, the instructions for PTF BPB1543 are designed for users who previously followed the instructions for applying PTF BPB1517. The situation that you described would occur only if a user applied BPB1543 without applying BPB1517.

        Aug 27, 2018 08:58
  2. Feli Brachthaeuser

    hello, jsut another question: In BBILIB member §§YZZ081 offer the same as @BBXINIT in BBSAMP. Can you please check this and added it to the doc? Sometimes a job is prefered, because you don't need to put it in an offical PROCLIB. best regards, Feli

    Mar 05, 2020 03:47
    1. Dov Kaiser

      Hi, Feli. Thank you for your question. We have forwarded it to the writer who is responsible for this content.

      Mar 05, 2020 06:58