Using the CICS Feature › SMF Information for CICS Transactions › How the CICS SMF Feature Works

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How the CICS SMF Feature Works

The CICS SMF Feature needs SMF Type 110 records with subtype 1 (CICS Monitoring). From these records, Class of Data = 1 (Dictionary) is used for verifying the existence and locating the offset of the relevant data. Class of Data = 3 (Performance) records contain one or more transaction-specific data according to the layout found in the dictionary record. These types of records must be activated and written to SMF data sets.

A dictionary record is created during CICS startup and it is relevant for that specific run. Every single CICS system on every single startup can contain a different layout of transaction performance information; however, this should not be the normal situation

A change in layout normally occurs when the CICS version is changed. The layout depends on the definition of the Monitoring Control Table (MCT).

Starting with the CICS SMF Feature for a specific CICS system is only possible after the startup of the region. Performance Management Assistant stores a dictionary information record containing the timestamp and processes only those transaction performance records after the stored timestamp

Every time Performance Management Assistant recognizes a new dictionary record for a specific CICS system, the information about the relevant fields is compared to the stored information. If there are no changes, the new dictionary record is ignored. When there are changes in the dictionary, Performance Management Assistant stores a new dictionary information record containing the new timestamp. All records after the timestamp are processed with the new layout, where older ones are processed with the layout for this specific time period. This assures the correct functionality even when SMF datas ets are not processed in the correct time sequence.

The CICS SMF Features uses the following fields from the Monitor Control Table:

Performance Group

Informal Name

Description

DFHTASK

TRAN

Name of the transaction

DFHTASK

TTYPE

Start type of the transaction

DFHCICS

START

Time that the user task was attached

DFHCICS

STOP

Time that the user task was detached

DFHDATA

IMSREQCT

Number of IMS (DBCTL) requests that were issued by the user task

DFHDATA

DB2REQCT

Number of DB2 (EXEC SQL and IFI) requests that were issued by the user task

DFHTASK

USRDISPT

Total elapsed time that the user task was dispatched

DFHTASK

USRCPUT

Processor time that the user task was dispatched

DFHTASK

SUSPTIME

Total elapsed time that the user task was suspended by the dispatcher

All of these fields must be included on every CICS system that is used for the CICS SMF Feature.

Use the following steps to create the data contents for the CICS SMF Feature:

  1. Extract the necessary information from SMF data sets to a temporary file
    (Module APCCASDI). CICS compressed data is handled with the installation of PTF PA460003.
  2. Sort the temporary files by CICS system, transaction, and start time.
  3. Process the sorted file and aggregate the detail information (module APCCASSA - at this time with 96 fixed intervals of 15 minutes (00:00 to 00:15, 00:15 to 00:30 and so on).
  4. Sort aggregated detail information file.
  5. Process the sorted file to create final record structures and store all records onto the data cluster (module APCCASSB).