ZPAGEOPT parameter
1 mb page areas
Summary
- Default value
- 0
- Parameter type
- System
- Where set
- On User 0's parameter line.
- Related products
- All
- Introduced
- Model 204 V7.4
Description
ZPAGEOPT is a User 0 parameter applicable to z/OS systems only.
ZPAGEOPT specifies the areas that should be allocated using 1MB pages.
The following settings are valid:
Note: Any non-zero setting of ZPAGEOPT fails if the containing load library is not APF authorized.
| Setting | Meaning |
|---|---|
| X'0001' | Use 1MB pages for servers above the bar.
Any server areas allocated above the bar (swappable (SERVGA) or non-swappable (SERVNSA)) will be allocated using 1MB pages. This improves LTB (look-aside translation buffer) hits by reducing the number and size of segment and page translation tables, resulting in a performance improvement for the Online. |
| X'0002' | Use 1MB pages for buffers above the bar. |
| X'0004' | Use 1MB pages for buffer hash cells above the bar. |
| X'0008' | Use 1MB pages for buffer control blocks above the bar. |
| X'0010' | Use 1MB pages for CCATEMP pages in storage above the bar. |
| X'0020' | Use 1MB pages for CCATEMP in storage control blocks. |
| X'0040' | Use 1MB pages for the record locking table when it resides above the bar. |
| X'0080' | Use 1MB pages for CCAAPSY (APSY saved compilations in storage above the bar). From V7.6 onwards, this allocation will not include Resident Requests (RESREQST). |