Using policy overrides

Once you have defined your service classes, you can determine whether any of your service class goals change at different times. If they do, you can define a policy override. With an override, you can change one or more of the following for a service policy:

A goal for a service class period
Number and duration of periods
A service class - resource group assignment
Resource group attributes
CPU protection.

Example 1: Policy overrides

In this example, the service class BATPIG is in the BATCH workload. It is associated with the resource group LIMIT. Suppose the LIMIT resource group is assigned some maximum capacity. BATPIG is assigned a discretionary goal. Since it is a discretionary goal, it does not have an assigned importance. In the Weekend policy, however, both the goal and the resource group association is overridden. The resource group association is overridden, so that in the Weekend policy, BATPIG is not assigned to a resource group. It is instead assigned a response time goal of 1 hour, with an importance of 5.

------------------ Base --------------------------------
    Policy: Standard                      Policy: Weekend
                                            (overrides)
  Service Class..... BATPIG
  Decription........ All batch CPU hogs
     Workload....... BATCH
     Resource Group. LIMIT                _________

  Period    Goal.... discretionary        1 hour AVG
    1       Import.. n/a                  5

Example 2: Policy overrides

In this example, the CICSHIGH service class is in the CICS® workload. In the Standard policy, it is assigned a response time goal of 1 second average, with an importance of 1. It is not assigned a resource group, because there is no business need to limit or guarantee capacity. For the weekend policy, however, it has an overridden goal. Because of a contract with CICS users, the agreed response time for weekends is 2 seconds average, with an importance of 2.

------------------ Base --------------------------------
    Policy: Standard                      Policy: Weekend
                                            (overrides)
  Service Class..... CICSHIGH
  Description....... All short CICS transactions
     Workload....... CICS
     Resource Group. ________             _________

  Period    Goal.... 1 sec avg            2 sec avg
    1       Import.. 1                    2

Example 3: Policy overrides

In this example, the resource group DEPT58 is associated with 3 service classes: 58CICS, 58TSO, and 58BATCH. Since the department is willing to pay for more capacity on the weekends, the minimum is overridden for the weekend policy. It is 1500 CPU service units per second. So in the weekend policy, the service classes 58CICS, 58TSO, and 58 BATCH have a minimum of 1500 CPU service units guaranteed.

------------------ Base --------------------------------
    Policy: Standard                      Policy: Weekend
                                            (overrides)

Resource Group...... DEPT58
Description......... Contracted capacity for dept. 58

  Minimum    1000                              1500
  Maximum    ________

  Service Class 58CICS__
                58TSO___
                58BATCH_