Chapter 3: Characterize Workloads › Create Transaction Workload Definitions

Create Transaction Workload Definitions

Transaction workload definitions contain groups of images with similar resource use. When creating a transaction workload definition, verify that the images included in the workload definition have similar service demands. Specifying images with similar service demands ensures that the reported system-wide image response times for transaction workload definitions are meaningful. For example, you might group all images that perform editing into a transaction workload definition. Similarly, all images that perform inquiries or database updates might be grouped into their respective transaction workload definition.

At installation, Performance Agent provides the transaction workload definitions SYSMAN, COMPILES, UTILITIES, EDITORS, and NETWORK. These workload definitions are used as the default if you do not define and use your own. Performance Agent requires that every transaction workload definition have at least one image name.

The following Parameter Editor examples create new transaction workload definitions:

1. To add the database update workload definition named DB_UPDATES with images CST_UPD, INV_UPD, and ORD_UPD, enter:

   PSDC-EDIT> ADD/WORKLOAD DB_UPDATES/IMAGENAMES=-
   _PSDC-EDIT> (CST_UPD,INV_UPD,ORD_UPD)
   

   To narrow the focus of a workload definition to specific images used by certain users, specify combinations of user criteria and image names. Specify that both must match before the resource use is allocated for the workload.

2. To add the writers editing workload definition (assuming all writers are in UIC group 200), enter

   PSDC-EDIT> ADD/WORKLOAD WRITER_EDITS/UIC=[200,*]-
   _PSDC-EDIT> /IMAGENAMES=(TPU,EDT,LSEDIT) /MATCH=BOTH
   

When you define a transaction workload, you have a choice of two types of transactions. You can specify image terminations or terminal responses. This choice determines how the software counts the number of transactions for a particular workload.

These options are as follows:

• Image terminations—The software counts the number of image terminations to measure the transactions.
• Terminal responses—The software counts the number of terminal QIO read completions for terminal devices to measure the transactions.

When you choose the terminal response option, the Performance Manager component provides information on terminal response time. This CA component breaks down workloads into smaller workloads based on differing levels of resource demands. This feature is called clustering.

To select transactions based on terminal response, use the /TRANSACTION_UNITS qualifier in the Parameter Editor. The format for this is

/TRANSACTION_UNITS=TERMINAL_RESPONSES

To select transactions based on image terminations, use the /TRANSACTION_UNITS qualifier in the Parameter Editor. The format for this is

/TRANSACTION_UNITS=IMAGE_TERMINATIONS