Creating a WLM environment for the Db2 Data Gate stored procedures

Create a dedicated Workload Manager (WLM) application environment for the Db2 Data Gate stored procedures.

1. Copy the <HLQSP>.SAQTMOD load-module data-set as <HLQACTIVE>.SAQTMOD for reference in your WLM procedure. Also copy the <HLQSP>.SAQTSAMP(AQTENV) member as <HLQACTIVE>.SAQTSAMP(AQTENV). This way, you can install updates on the data sets that are controlled by SMP/E under <HLQSP> without affecting your running database environment.
2. Create a separate Workload Manager (WLM) environment for the Db2 Data Gate stored procedures. Use the following properties:

   Appl Environment Name . . DSNWLMV9
   Description . . . . . . . Db2 V11 default Stored Procedures for Data Gate
   Subsystem type  . . . . . Db2
   Procedure name  . . . . . DSNWLM
   Start parameters  . . . . Db2SSN=&IWMSSNM,APPLENV=DSN
   . . . . . . . . . . . . . WLMV9

   Important:

   • DSNWLMV9 is an example. The value that you must enter here is the one used for the !WLMENV! placeholder in the AQTTIJSP job.
   • The procedure name (in this example: DSNWLM) must match the name of the defined procedure that you use to start the WLM-managed address space.
   • The task that is started by the WLM-managed address space is run under a certain user ID. An OMVS segment must be defined for this user ID.
   • Do not specify a value for NUMTCB in the Start parameters section of the definition because this value takes precedence, and thus makes it impossible to set the value by running the JCL that is discussed in the next paragraph.
   You might want to modify the following template, which contains a procedure for the WLM-managed address space started task. The template includes the required STEPLIB and DD names.

   //*************************************************************
   //* PROCEDURE NAME = DSNWLM
   //*
   //*    JCL FOR RUNNING THE WLM-ESTABLISHED STORED PROCEDURES
   //*    ADDRESS SPACE
   //*       RGN     -- THE MVS REGION SIZE FOR THE ADDRESS SPACE.
   //*       Db2SSN  -- THE Db2 SUBSYSTEM NAME.
   //*       NUMTCB  -- THE NUMBER OF TCBS USED TO PROCESS
   //*                  END USER REQUESTS.
   //*       APPLENV -- THE MVS WLM APPLICATION ENVIRONMENT
   //*                  SUPPORTED BY THIS JCL PROCEDURE.
   //*
   //*       Db2VERS -- Db2-VERSION (I.E. V110)
   //*                  SET BY APPLICATION ENVIRONMENT
   //*                      DSNWLMV9 ==> V110
   //*
   //*    The user ID that is used to start the task must have 
   //*    read access to the <HLQs> in the STEPLIB statement
   //*
   //*************************************************************
   //DSNWLMV9  PROC RGN=0K,APPLENV=DSNWLMV9,NUMTCB=15
   //IEFPROC  EXEC PGM=DSNX9WLM,REGION=&RGN,TIME=NOLIMIT,
   //         PARM='&Db2SSN,&NUMTCB,&APPLENV'
   //STEPLIB  DD  DISP=SHR,DSN=<HLQDb2SSN>.SDSNEXIT
   //         DD  DISP=SHR,DSN=<HLQBASE>.SDSNLOAD
   //         DD  DISP=SHR,DSN=<HLQBASE>.SDSNLOD2
   //         DD  DISP=SHR,DSN=<HLQACTIVE>.SAQTMOD
   //SYSTSPRT DD    SYSOUT=A
   //CEEDUMP  DD    SYSOUT=H
   //OUT1     DD    SYSOUT=A
   //UTPRINT  DD    SYSOUT=A
   //DSSPRINT DD    SYSOUT=A
   //SYSPRINT DD    SYSOUT=A
   //AQTENV   DD    DSN=<HLQACTIVE>.SAQTSAMP(AQTENV),DISP=SHR
   //AQTDEF6  DD    DSN=<HLQACTIVE>.SAQTSAMP(AQTDEF6),DISP=SHR
   

   Important:

   • To avoid conflicts with environment variables that are set for stored procedures of other applications, create a WLM application environment that is exclusively used by the Db2 Data Gate stored procedures.

     The stored procedures occasionally use the SYSPRINT output for diagnostic messages. For example, restart attempts for DSNUTILU, which might indicate inappropriately configured workload classes, are recorded here. Make sure to define a valid destination for SYSPRINT that grants write access to all users of the stored procedures. Otherwise, authorization failures will be recorded even if SYSPRINT was not used at all.

   • The Db2 Data Gate stored procedures call the following Db2 for z/OS stored procedures:
     • SYSPROC.ADMIN_INFO_SYSPARM
     • SYSPROC.DSNUTILU

     In addition, the Db2 stored procedure SYSPROC.ADMIN_COMMAND_DB2 is called by the AQTTIJSP installation job and by the web interface on IBM Cloud Pak® for Data.

     Run these Db2-supplied stored procedures in a separate WLM application environments that is not shared with the Db2 Data Gate stored procedures.

   • If your system has more than one IP stack, you must unequivocally identify the stack that the Db2 Data Gate stored procedures are supposed to use. To do so, add the following statement to the procedure that starts the address space:

     //SYSTCPD DD    DISP=SHR,DSN=<TCPIP.DATA file>

     Make sure that the z/OS UNIX System Services are configured to use the same IP stack. Connectivity from UNIX System Services to the Db2 Data Gate is required for diagnostic and service purposes.

   • You might want to change the default settings for Db2 Data Gate stored procedures, especially if you want to use parallel processing for loading tables. To do so, you must set the environment variables in the AQTENV data set accordingly.
     Notes:

     • If you must set environment variables, use the sample AQTENV data set member that came with this version of the product. Do not re-customize an older version of AQTENV because fundamental settings might have changed and using an old configuration might lead to problems.
     • The value of NUMTCB must be in the range between 15 and 30 (inclusively), so as not to exceed the 31-bit memory limits of the stored procedures.

     For more information, in particular about the relationship between NUMTCB and AQT_MAX_UNLOAD_IN_PARALLEL, see Environment variables.