Classifying z/OS workload

You can use a common workload classification document to classify inbound HTTP, IIOP, Session Initiation Protocol (SIP), optimized local adapter, and message-driven bean (MDB) work requests for the z/OS® workload manager.

1. Develop the workload classification document.
   Use the information in the Workload classification file topic to create the document. The topic contains examples of the workload classification document, with and without RAS attributes. Use one workload classification document whether you are using it to classify z/OS workload or to implement Reliability Availability and Serviceability (RAS) granularity.
2. If you create the document on a z/OS system in code page IBM®-1047, the normal code page for files that exist in the HFS, convert the file to ASCII before you use the file.
   Use one of the following options to convert a working document into a document that can be used by the server:

   • native2ascii
     This is a utility in the Java™ SDK that can convert a file from the native code page to the ASCII code page. For example, if you are working on an XML document called x5sr02.classification.ebcdic.xml and you want to create a document called x5sr02.classification.xml, use the following command:

     /u/userid -> native2ascii \
     x5sr02.classification.ebcdic.xml > x5sr02.classification.xml

     The command line is split with the backslash (\) character to the next line for publication purposes.
   • iconv
     This is a z/OS utility that can convert files from one designated code page to a different designated code page. For example, if you are working on an XML document called x5sr02.classification.ebcdic.xml and you want to create a document called x5sr02.classification.xml, use the following command:

     /u/userid -> iconv -f IBM-1047 -t UTF-8 \
     x5sr02.classification.ebcdic.xml >x5sr02.classification.xml

     The command line is split with the backslash (\) character to the next line for publication purposes.
   • Create the document on your workstation and then FTP the file to the correct location on the z/OS system in binary format. By using this option, you can also create the Classification.dtd file in the same directory as the workload classification document. Then, you can perform an XML validity check on the document before installing it on a server. Use any type of validating parser, for example, you can use WebSphere Application Developer workbench to construct and validate the workload classification document.
3. Specify the location of the workload classification document in the administrative console.
   Use the wlm_classification_file variable to specify the XML file that contains the classification information. In the administrative console, click Environment > WebSphere variables > New. You can set the variable at cell, node, or server instance level. If you specify the variable at the cell or node level, the information must be accessible and applicable to all the servers that inherit the specification from the node or cell.
4. Perform z/OS Workload Manager actions that are required to use the TCLASS values.
   Each TCLASS must be assigned a service class, report service class, or both to the enclave under which the work runs. The CB classification rules must be updated.

   If you want to classify work for message-driven beans deployed against JCA 1.5 resources with the default messaging provider, or you want to classify mediation work for use with service integration buses, you need to perform z/OS Workload Manager actions that are required to use the TCLASS value SIBUS.

   Transaction classes are used as sub-rules in establishing service classes and transaction. The TCLASS values are not used as level one rules. If you decide to use TCLASS as a level one rule rather than a sub-rule, you must be careful in ordering the rules. The first level one rule that applies to the work is used, so more specific rules should be first, followed by the broad rules.

   For example, consider the following two examples of CB classification rules:

   Subsystem-Type Xref Notes Options Help
   --------------------------------------------------------------------------
   Modify Rules for the Subsystem Type Row 1 to 17 of 17
   Command ===> ____________________________________________ SCROLL ===> CSR
   Subsystem Type . : CB Fold qualifier names? Y (Y or N)
   Description . . . CB Class'n w/WLM Trans. CLASSes
   Action codes: A=After C=Copy M=Move I=Insert rule
   B=Before D=Delete row R=Repeat IS=Insert Sub-rule
   More ===>
          --------Qualifier--------               -------Class--------
   Action   Type   Name   Start                       Service Report
   																		DEFAULTS:  CBCLASS RWASDEF
   ____ 1 	CN  P5SR01* 	1                         CBCLASS RTP5CLUS
   ____ 1 	TC      A0     ___                        CBHUTCH RP5A0
   ____ 1 	TC      A1     ___                        CBHUTCH RP5A1
   ____ 1 	TC      A1B    ___                        CBHUTCH RP5A1B
   ____ 1 	CN    WSIVP2*  ___                        CBSLOW  RWSIVP
   ____ 1 	CN    T%SERV*  1                          CBFAST  RTSMIGT
   ____ 1 	CN      B4*    ___                        CBFAST ________

   In the preceding example, the TCLASS assignments that are made for enclaves running in the server P5SR01x are never used by the workload manager. When the following rule is run, no further searching of the classification table is done:

   ____ 1 	CN   	P5SR01* 	1 												CBCLASS 

   The TCLASS assignments are not used. All of the enclaves that run in the P5SR01x servers are assigned to the CBCLASS service class and the RTP5CLUS report service class.

   Subsystem-Type Xref Notes Options Help
   --------------------------------------------------------------------------
   Modify Rules for the Subsystem Type Row 1 to 17 of 17
   Command ===> ____________________________________________ SCROLL ===> CSR
   Subsystem Type . : CB Fold qualifier names? Y (Y or N)
   Description . . . CB Class'n w/WLM Trans. CLASSes
   Action codes: A=After C=Copy M=Move I=Insert rule
   B=Before D=Delete row R=Repeat IS=Insert Sub-rule
   More ===>
            --------Qualifier--------            -------Class--------
   Action   Type    Name    Start                Service       Report
                                       DEFAULTS: CBCLASS       RWASDEF
   ____ 1   TC      A0     ___                CBHUTCH      RP5A0
   ____ 1   TC       A1       ___                CBHUTCH      RP5A1
   ____ 1 	 TC      A1B      ___                CBHUTCH      RP5A1B
   ____ 1 	CN     P5SR01*     1                 CBCLASS      RTP5CLUS
   ____ 1   CN     WSIVP2*    ___                CBSLOW       RWSIVP
   ____ 1   CN     T%SERV*     1                 CBFAST       RTSMIGT
   ____ 1   CN       B4*      ___                CBFAST       ________

   In the preceding example, if a TCLASS value of A0, A1, or A1B are provided in the classification, they are used regardless of which server is running the work. In this case, the server name is used only if these three TCLASS values are not present.
5. Implement the changes to the file.
   You can restart the application server or reload the workload classification document without having to restart the server:

   • Restart the application server.
   • Reload the workload classification document by issuing the following command:

     MODIFY|F <servername>,	RECLASSIFY,FILE='/path/to/newfile.xml'

   If the workload classification document is not a well formed, valid XML document it is ignored by the application server and the following message is displayed:

   BBOJ0085E PROBLEMS ENCOUNTERED PARSING WLM CLASSIFICATION XML FILE (0)

6. Use the DISPLAY WORK operator command to display classification information. Use this command to determine if your classification scheme is classifying the work as you intended.
   Issue the following command to display the IIOP, HTTP, internal, SIP, MDB, and optimized local adapter classification information:

   MODIFY|F <servername>,	DISPLAY,WORK,CLINFO

   Issue this command against each application server.

   The following example shows a possible result of issuing the new operator command:

   00- SY1  f bbos001,display,work,clinfo                                      
         SY1  BBOJ0129I: The /tmp/wlm4.class.xml workload classification file was loaded at   
         2009/07/14 19:33:35.297 (GMT).                                           
         SY1  BBOO0281I CLASSIFICATION COUNTERS FOR IIOP WORK                    
         SY1  BBOO0282I CHECKED 0, MATCHED 0, USED 0, COST 2, DESC: IIOP root    
         SY1  BBOO0282I CHECKED 0, MATCHED 0, USED 0, COST 4, DESC: leotag       
         SY1  BBOO0282I CHECKED 0, MATCHED 0, USED 0, COST 3, DESC: byetag       
         SY1  BBOO0282I CHECKED 0, MATCHED 0, USED 0, COST 4, DESC: hellotag     
         SY1  BBOO0283I FOR IIOP WORK: TOTAL CLASSIFIED 0, WEIGHTED TOTAL COST 0 
         SY1  BBOO0281I CLASSIFICATION COUNTERS FOR HTTP WORK                    
         SY1  BBOO0282I CHECKED 2, MATCHED 2, USED 0, COST 2, DESC: HTTP root    
         SY1  BBOO0282I CHECKED 2, MATCHED 2, USED 0, COST 4, DESC: plantta4     
         SY1  BBOO0282I CHECKED 2, MATCHED 1, USED 1, COST 3, DESC: giftag4      
         SY1  BBOO0282I CHECKED 1, MATCHED 1, USED 1, COST 4, DESC: jpgtag4      
         SY1  BBOO0283I FOR HTTP WORK: TOTAL CLASSIFIED 2, WEIGHTED TOTAL COST 7 
         SY1  BBOO0188I END OF OUTPUT FOR COMMAND DISPLAY,WORK,CLINFO            

   An explanation of the command output follows:

   • BBOJ0129I: The file workload classification file was loaded at time. The message indicates the workload classification file currently active and the time that it was loaded.

   • BBOO0281I CLASSIFICATION COUNTERS FOR type WORK. The header message for messages that display the usage of the workload classification rules. The value of type can be HTTP, IIOP, INTERNAL, SIP, OLA, or MDB.
     Important: The display command does not include output for the classification type of SIBUS.

   • BBOO0282I CHECKED n1, MATCHED n2, USED n3, COST n4, DESC: text. This message displays information about a particular rule in the workload classification. This message displays the following information:
     • n1 - The number of times the rule has been examined.
     • n2 - The number of times that this rule has been matched by the request.
     • n3 - The number of times that this rule has been used.
     • n4 - The cost of using the rule, or the number of compares that are required to determine if this rule is the correct rule to use.
     • text - The descriptive text from the classification rule so that you can tell which classification rule is being displayed.
     The total cost n2 divided by the total number of requests classified n1 equals the cost of using the table. The closer that the value is to one, the lower the cost of using the defined rules. A value of 1 indicates that there is just the default classification, so no requests match it.
7. Repeat these steps until you achieve your optimal workload distribution and costs.