Defining the IMS DRA startup parameter table

The DRA startup parameter table provides the parameters needed to define the interface to the DBCTL subsystem.

About this task

You create the DRA startup parameter table by assembling the DFSPRP macro and link-editing it into the IMS.RESLIB library (or another APF-authorized library) as DFSPZPxx, where xx=00, for the default, or any other alphanumeric characters. Unless your IMS RESLIB uses the default name IMS.RESLIB, supplied in DFSPZP00, you must specify the name you have chosen in your version of the DRA. In Example JCL to generate a DRA startup table, the name IMS.RESLIB is used.

Note: The macro used is DFSPRP, but the name of the module you must link edit is DFSPZPxx. You must also link edit the DRA into an authorized library that is part of the CICS® STEPLIB concatenation.
The DFSPRP macro has the following parameters:
  • DSECT=NO

    A DSECT statement for PZP is not generated. You must specify this option in order to create a CSECT, which is required in order to assemble the module DFSPZPxx.

  • FUNCLV=

    The CCTL (in this case, CICS) functional level. The default (and the only valid value) is 1.

  • DDNAME=

    A 1- to 8-character ddname to be used with dynamic allocation of the DRA RESLIB. The default is CCTLDD.

  • DSNAME=

    A 1- to 44-character data set name of the DRA RESLIB. The default is IMS.RESLIB.

  • DBCTLID=xxxx

    The 1- to 4-character name of the DBCTL address space. The default is SYS1. This parameter must be the same as the IMSID in the DBCTL startup procedure for the DBCTL to which you want this CICS to connect. You can connect multiple CICS systems to the same DBCTL, but a CICS system can connect to only one DBCTL at a time.

  • USERID=xxxxxxxx

    CICS users do not specify this parameter; it is supplied by CICS itself. If you do specify anything, CICS overrides it. USERID is the 1- to 8-character name of the CICS address space (or CCTLID). The value CICS supplies when it connects to DBCTL is the CICS APPLID.

  • MINTHRD=xxx

    This parameter specifies the number of threads for this CICS system that, once initialized, remain created while the DRA is active. These threads remain allocated until this CICS system is disconnected from DBCTL, except if a thread is stopped by a /STOP command or by a thread failure. Additional threads are created, up to the number specified in MAXTHRD, or the number specified in MAXREGN, or the maximum of 999, whichever of these values is the lowest. These additional threads (not the MINTHRDs) are released when there is not enough system activity to require them. The maximum value you can specify for MINTHRD is 999, and the default is 1. For information about specifying values for MINTHRD, see Specifying numbers of threads. See also MAXREGN in IMS system generation macros used by DBCTL.

  • MAXTHRD=xxx

    This parameter specifies the maximum number of transactions for which this CICS system can have PSBs scheduled in DBCTL. Any schedule requests that are over this limit are queued in the DRA. You can balance the load sent to a single DBCTL from multiple CICS systems by specifying appropriate values for MAXTHRD in each CICS.

    The maximum value you can specify for MAXTHRD is 999 (but it should not exceed the value specified for MAXREGN) and the default is 1, or the value you specified in MINTHRD. For information about specifying values for MAXTHRD, see Specifying numbers of threads. See also MAXREGN in IMS system generation macros used by DBCTL.

  • TIMER=xx

    The frequency, in seconds, with which CICS is to repeat attempts to connect to DBCTL when connection has failed and the console operator has requested that CICS wait for connection in reply to a DFS690 message (rather than canceling the connection attempt). You can specify any value from 0 through 99. However, note that if you specify 0, the default value is used. The default is 60.

  • CNBA=xxx

    The total number of DEDB buffers that are allocated for this CICS system. The default is 0.

  • FPBUF=xxx

    The number of DEDB buffers to be allocated and fixed per thread. The default is 0. See DEDB performance and tuning considerations for information about defining DEDB buffer pools.

  • FPBOF=xxx

    The number of DEDB overflow buffers to be allocated per thread. The default is 0. See DEDB performance and tuning considerations for information defining DEDB buffer pools.

    Notes:
    1. For DBCTL users, fast path support refers only to DEDBs. Parameters that begin with FP refer to DEDBs in the DRA startup table.
    2. You do not need the parameters CNBA, FPBUF, and FPBOF if you are not using DEDBs.
    3. For detailed guidance on specifying DEDB buffers, see System administration in IMS product documentation .
  • TIMEOUT=xxx

    The amount of time, in seconds, that CICS should wait for a DRA TERM request to complete. The maximum value is 999, and the default is 60. For guidance on what to specify, see TIMEOUT in CICS failure.

  • SOD=x

    The output class to be used for a snap memory dump of abnormal thread terminations. The default is A. See Dumps produced by the DRA for more information about these memory dumps.

  • AGN=xxxxxxxx

    The 1- to 8-character application group name (AGN). You must use this parameter only if you have specified AGN security checking for DBCTL. There is no default. See Security checking with DBCTL for more information.

  • OPENTHRD={CCTL | DISABLE}

    This parameter specifies whether DRA Open Thread support processing is enabled. CCTL is the default, and when this is specified, the DRA uses CICS TCBs for processing instead of dedicated IMS DRA TCBs, enabling increased parallelism. To disable DRA Open Thread support processing, specify DISABLE