ZPAGEOPT parameter: Difference between revisions
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<var>ZPAGEOPT</var> is a User 0 parameter applicable to z/OS systems only. </p> | <var>ZPAGEOPT</var> is a User 0 parameter applicable to z/OS systems only. </p> | ||
<p> | <p> | ||
<var>ZPAGEOPT</var> specifies the areas that should be allocated using 1MB pages.</p> | <var>ZPAGEOPT</var> specifies the areas that should be allocated using [[Performance_monitoring_and_tuning#1MB_virtual_pages|1MB pages]].</p> | ||
<p> | <p> | ||
The following settings are valid:</p> | The following settings are valid:</p> | ||
<p class="note"><b>Note:</b> Any non-zero setting of <var>ZPAGEOPT</var> fails if the containing load library is not APF authorized. </p> | |||
<table> | <table> | ||
<tr class="head"><th>Setting</th><th>Meaning</th></tr> | <tr class="head"><th>Setting</th><th>Meaning</th></tr> | ||
<tr><th | <tr><th><var>X'0001'</var></th><td>Use 1MB pages for servers above the bar. | ||
<p> | |||
Any server areas allocated above the bar (swappable (<var>[[SERVGA parameter|SERVGA]]</var>) or non-swappable (<var>[[SERVNSA parameter|SERVNSA]]</var>)) 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. | |||
</p></td></tr> | |||
<tr><th align="right"><var>X'0002'</var></th><td>Use 1MB pages for buffers above the bar.</td></tr> | <tr><th align="right"><var>X'0002'</var></th><td>Use 1MB pages for buffers above the bar.</td></tr> | ||
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<tr><th align="right"><var>X'0008'</var></th><td>Use 1MB pages for buffer control blocks above the bar.</td></tr> | <tr><th align="right"><var>X'0008'</var></th><td>Use 1MB pages for buffer control blocks above the bar.</td></tr> | ||
<tr><th align="right"><var>X'0010'</var></th><td>Use 1MB pages for CCATEMP pages in storage above the bar.</td></tr> | <tr><th align="right"><var>X'0010'</var></th><td>Use 1MB pages for [[Using_the_system_scratch_file_(CCATEMP)|CCATEMP]] pages in storage above the bar.</td></tr> | ||
<tr><th align="right"><var>X'0020'</var></th><td>Use 1MB pages for CCATEMP in storage control blocks.</td></tr> | <tr><th align="right"><var>X'0020'</var></th><td>Use 1MB pages for CCATEMP in storage control blocks.</td></tr> | ||
Latest revision as of 11:33, 14 December 2017
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). |