gtpo1mgvOperations

ZVFAC DEFINE-Define VFA Resources

Use this command to change buffer ratios, reserve chain sizes, and define the buffer reuse threshold value for virtual file access (VFA).

Requirements and Restrictions

You can enter this command only for the basic subsystem (BSS).

Format




Notes:

  1. You can also separate the parameters with the , character.

RAT381
defines the 381 VFA buffer ratio.

RAT1055
defines the 1055 VFA buffer ratio.

RAT4095
defines the 4095 VFA buffer ratio.

buffer
is a buffer ratio from 1-999.

RES381
defines the reserve chain size for the 381 VFA buffer.

RES1055
defines the reserve chain size for the 1055 VFA buffer.

RES4095
defines the reserve chain size for the 4095 VFA buffer.

chain
is a reserve chain size percentage from 1-99. The reserve chain destages the VFA buffers that are delay file pending before the buffers are needed by VFA for new records.

The recommended values are:

Count-threshold
defines the buffer reuse threshold value, where threshold is a value from 1-999.

Additional Information

Examples

The buffer ratios, reserve chain sizes, and the reuse threshold value are changed in the following example.

+--------------------------------------------------------------------------------+
|User:   ZVFAC DEF RAT1-10 RAT3-5 RAT4-3 RES1-5 RES3-10 RES4-15 C-36             |
|                                                                                |
|System: VFAC0006I 13.12.15  VFA KEYPOINT VALUES ARE:                            |
|             RAT1055- 10, RAT381-  5, RAT4095-  3                               |
|             RES1055-  5, RES381- 10, RES4095- 15                               |
|             COUNT- 36                                                          |
|                         CURRENT VFA VALUES ARE:                                |
|             RAT1055-  1, RAT381-  1, RAT4096-  1                               |
|             RES1055- 20, RES381- 20, RES4096- 20                               |
|             COUNT- 36                                                          |
+--------------------------------------------------------------------------------+

Related Information

See TPF Database Reference for more information about VFA, buffer ratios, reserve chain sizes, and the reuse threshold value.