MPSYS parameter: Difference between revisions
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<dd>All | <dd>All | ||
<dt>Introduced | <dt>Introduced | ||
<dd><var class="product">Model 204 | <dd><var class="product">Model 204 V5.1</var> | ||
</dl> | </dl> | ||
==Description== | ==Description== | ||
<p>This parameter indicates a system-wide MP/204 processing option and applies only to z/OS.</p> | <p> | ||
This parameter indicates a system-wide <var>[[Performance_monitoring_and_tuning#Multiprocessing_.28MP.2F204.29|MP/204]]</var> processing option and applies only to z/OS.</p> | |||
<p>This parameter is ignored when Model 204 is not running with MP/204 enabled.</p> | |||
<table> | <table> | ||
<tr><th>Setting </th><th>Meaning </th><th | <tr class="head"><th>Setting </th><th>Meaning </th><th>Purpose</th></tr> | ||
</th></tr> | <tr><th><var>X'01' </var></th> | ||
<tr><th | <td>A thread should continue spinning on an MP lock even if it appears that the task holding the lock cannot be dispatched.</td> | ||
<td>In many situations, continuing to spin provides better performance than doing an operating system wait for the lock to free up.</td></tr> | |||
</td></tr> | |||
<tr><th | <tr><th><var>X'02'</var></th> | ||
<td>A thread should stay on the maintask after getting a critical file resource.</td> | |||
</td></tr> | <td>To improve performance at an MP/204 site that is encountering a lot of task switching (a high STDEQ system statistic) and a lot of critical file resource conflicts. </td></tr> | ||
</table> | </table> | ||
[[Category:System parameters]] | [[Category:System parameters]] | ||
[[Category:Parameters]] | [[Category:Parameters]] | ||
Latest revision as of 16:36, 30 March 2017
MP/204 system flags
Summary
- Default value
- 0
- Parameter type
- System
- Where set
- On User 0's parameter line or reset by system manager
- Related products
- All
- Introduced
- Model 204 V5.1
Description
This parameter indicates a system-wide MP/204 processing option and applies only to z/OS.
This parameter is ignored when Model 204 is not running with MP/204 enabled.
| Setting | Meaning | Purpose |
|---|---|---|
| X'01' | A thread should continue spinning on an MP lock even if it appears that the task holding the lock cannot be dispatched. | In many situations, continuing to spin provides better performance than doing an operating system wait for the lock to free up. |
| X'02' | A thread should stay on the maintask after getting a critical file resource. | To improve performance at an MP/204 site that is encountering a lot of task switching (a high STDEQ system statistic) and a lot of critical file resource conflicts. |