Using WLMTUNING=YES

For this scenario, assume that the following conditions exist in your environment:

  • The workloads are governed by different WLM policies.
  • The WLM policies managing the workloads are sufficiently different. That is, an importance value of n on one sysplex is not comparable to an importance value of n on another sysplex.

Related topic

Entitlement-scenarios

Also, assume that you want to set the order in which LPARs and groups receive MSUs based on:

  • Adjusted Low-Importance Workload Percentage
  • Priority
  • Ratio (4HRA ÷ entitlement)

Rules

If WLMTUNING=YES, the following rules apply when LPARs or groups have 4HRAs above entitlement:

  • If LPARs or groups belong to the same sysplex, the LPAR or group with the lowest Adjusted Low-Importance Workload Percentage is favored.

    If the LPARs or groups have equal Adjusted Low-Importance Workload Percentage, the LPAR or group with the lowest ratio 4HRA/entitlement is favored.

  • If LPARs or groups belong to separate sysplexes, the LPAR or group with the highest priority is favored.

    If the LPARs or groups have equal priority, the LPAR or group with the lowest ratio of 4HRA/entitlement is favored.

Important

LPARs or groups that have 4HRAs below entitlement receive the MSUs to which they are entitled and additional MSUs to ensure that they are not accidentally capped. For more information, see Overview-of-entitlement.


Scenario

As the following view shows, GROUPGGG has a 4HRA below entitlement. Therefore, it receives the MSUs to which it is entitled, and the GCL is set slightly above the 4HRA.

GUID-B762B831-2F74-4BCC-91FC-47C8EE7FF38A-low.png

In contrast, LPARAAA, LPARBBB, LPARCCC and GROUPHHH have 4HRAs above their entitlement and must compete for the remaining 23 gray-space MSUs from GROUPGGG. (For an explanation of how to calculate gray-space MSUs, see Using-WLMTUNING-NO.)

  • From each sysplex, a sysplex winner is selected.
  • Among the sysplex winners, a winner is selected.

For more information about how sysplexes are favored, see Rules.

The sysplex-winners are determined as follows:


Sysplex

LPAR/group

Adjusted Low-Importance Workload Percentage

Sysplex winner

SYSPLXII

LPARAAA

8

LPARAAA

LPARBBB

10

SYSPLXOO

GROUPHHH

10

GROUPHHH

LPARCCC

12

Among the sysplex-winners, LPARAAA wins over GROUPHHH because it has the higher priority value of 2.

The gray-space MSUs are distributed as follows:

  • LPARAAA has the highest priority of the sysplex-winners. iCap determines that LPARAAA requires 10 of the gray-space MSUs:

    110 (4HRA) - 100 (entitlement) = 10

    This distribution leaves 13 remaining gray-space MSUs:

    23 (gray-space MSUs) - 10 (MSUs required by LPARAAA) = 13

  • LPARBBB (the remaining LPAR on SYSPLXII) and GROUPHHH (the sysplex winner on SYSPLXOO) compete for gray-space MSUs.

    LPARBBB and GROUPHHH have an equal priority value of 3 and an equal Adjusted Low-importance Workload Percentage of 10, so iCap will distribute the remaining gray-space MSUs based on entitlement (or proportion). Because GROUPHHH has the lowest ratio of 4HRA/entitlement (as shown in the following table), GROUPHHH will receive the next distribution:

    LPAR or group

    4HRA

    Entitlement

    Ratio 4HRA/entitlement

    LPARBBB

    100

    75

    1.33

    GROUPHHH

    150

    125

    1.2

  • iCap calculates that GROUPHHH is allowed to take the remaining 13 gray-space MSUs. However, GROUPHHH does not receive enough MSUs to meet the 4HRA (150). Consequently GROUPHHH is soft-capped.
  • As there are no remaining gray-space MSUs, iCap sets the DC of LPARBBB to 75 and the DC of LPARCCC to 25 (equal to entitlement). That is, LPARBBB and LPARCCC are soft-capped.

 

Tip: For faster searching, add an asterisk to the end of your partial query. Example: cert*