7. PARAMETERS › 7.3 Unit Level Parameters › 7.3.9 APPC/MVS Application Unit Definition (ATPAPU)

7.3.9 APPC/MVS Application Unit Definition (ATPAPU)

The APPC/MVS Transaction file (BATATP) provides a means to
characterize APPC/MVS ASCH-scheduled Transaction Programs
(TPs) as application units.  The Application Unit Identifier
(ATPAPU) is a user-defined data element used to classify
ASCH-scheduled TPs based on common workload characteristics.

Since ASCH-scheduled TPs are transaction-like programs and
response time measurements are provided with the BATATP
duration data elements, it is useful to be able to
characterize the ASCH TP workload into groups of related
resource requirements.  This is the purpose of the ATPAPU
data element.  It is used as a sort/sequence data element in
the various BATATP file timespans and is useful for
performance analysis studies of large numbers of TPs with
similar workload requirements.  Several approaches can be
used to define the ATPAPU value and are discussed below:

    o  Classification by TP Class

       This approach classifies TPs based on the initiator
       class where the TP executed.  This is probably the
       best classification approach available since each
       ASCH-scheduled TP must be defined to execute in an
       APPC initiator of a particular class.  Each TP Class
       is defined in the SYS1.PARMLIB(ASCHPMxx).  The class
       definition includes the class name, minimum and
       maximum numbers of initiators allowed for the class,
       and, most importantly, a response time goal.  The
       response time goal specifies, in seconds, the
       acceptable amount of time your installation expects
       the TP to complete execution.  Expected queue time
       delay is included in the response time goal.

     o  Classification by Transaction Name

       This approach classifies the APPC/MVS ASCH-scheduled
       TP workload by TP Name (ATPNAME).  Because the TP Name
       itself can be 64 characters in length, it is a poor
       candidate for inclusion in the higher timespans due to
       excessive space requirements.  By using standardized
       TP naming conventions, ASCH-scheduled TPs can be named
       so that the first 1 to 12 characters characterize the
       resource requirements of the TP.  A SAS substring
       function could be used with the TP Name as the
       argument to provide the value for the ATPAPU data
       element.  Another approach would be to use a table
       lookup to translate each TP Name to the corresponding
       ATPAPU value.

    o  Classification by TP Type

       This approach classifies TPs based on type of TP
       executed: standard or multi-trans.  The multi-trans
       scheduled TP is further defined as either the TP part
       or the shell part.  Classification by TP Type is not
       recommended because ATPTYPE is already included in all
       timespans of the BATATP file as a sort/sequence data
       element.

    o  Classification by User

       This approach classifies transaction data according to
       the user who requested the APPC/MVS ASCH-scheduled TP.
       This method can use various ways to extract the
       identity of the requesting partner TP from the data
       elements found in the BATATP file.


DEFINING THE APPLICATION UNIT

The CA MICS data element ATPAPU contains the application unit
identifier, which is used by the APPC/MVS Transaction File
(BATATP) as a part of the file key.  Any information from any
data element derived from the SMF type 33 APPC/MVS TP
Accounting record (such as TP Class or TP Name) can be stored
in this 12-byte field by the application unit derivation exit
APPCAURT (see Section 7.3.10, Application Unit Derivation
Routine (APPCAURT)).

Notes:

1.  Certain groups of transactions may be of more interest
    when considered as a group than when considered by
    individual TP Name.  Examples of such transactions are:

    o  Trivial, high-volume low-resource consumption routines
       identified by the TP Class.

    o  Resource-intensive, low-volume transactions.

    Grouping transaction data in the APPCAURT routine greatly
    decreases the amount of storage needed to represent
    application unit data in the CA MICS database.

2.  Any data element that could be useful in later reporting
    from the higher timespan APPC/MVS Transaction File
    (BATATP) that is not appropriate for the ACCTNOx user-
    defined accounting data elements MUST be coded into the
    application unit identifier if the data element is not
    contained in the rest of the record.  For example,
    ATPCLASS (TP Class) is not carried in the higher
    timespans of the BATATP file.  Because ASCH-managed TP
    classes are defined with specific response goals, it may
    be useful to use the class value for TP performance
    analysis at the higher timespans.