AMPSUBZ parameter: Difference between revisions
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==Description== | ==Description== | ||
<p> | <p> | ||
This parameter applies to z/OS only.</p> | |||
<p> | <p> | ||
On a z/OS system, <var class="product">Model 204</var> zIIP support enables you to offload <var class="product">Model 204</var> work from regular processors to zIIP processors.</p> | On a z/OS system, <var class="product">Model 204</var> zIIP support enables you to offload <var class="product">Model 204</var> work from regular processors to zIIP processors. <var>AMPSUBZ</var> specifies the number of active zIIP subtasks.</p> | ||
<p> | <p> | ||
<var>AMPSUBZ</var> | The value of <var>AMPSUBZ</var> must be less than or equal to the value of the <var>[[NMPSUBZ parameter|NMPSUBZ]]</var> parameter, which determines the number of zIIP subtasks attached during initialization. </p> | ||
< | <blockquote class="note"> | ||
<p><b>Note:</b> MP subtasks and zIIP subtasks may be used together. Therefore, <var>[[AMPSUBS parameter|AMPSUBS]]</var>, <var>[[NMPSUBS_parameter|NMPSUBS]]</var>, <var>AMPSUBZ</var> and <var>[[NMPSUBZ_parameter|NMPSUBZ]]</var> can all be greater than zero. However, to avoid unnecessary overhead: </p> | |||
<ul> | <ul> | ||
<li> | <li>Do not set <var>AMPSUBS</var> greater than the number of central processors actually available.</li> | ||
Do not set <var>AMPSUBS</var> greater than the number of central processors actually available.</li> | |||
<li> | <li>Do not set <var>AMPSUBZ</var> greater than the number of zIIP processors actually available.</li> | ||
Do not set <var>AMPSUBZ</var> greater than the number of zIIP processors actually available.</li> | |||
</ul> | </ul> | ||
<p>For more information about zIIP processing, refer to [[Performance monitoring and tuning#Offloading Model 204 work to zIIP processors|Offloading Model 204 work to zIIP processors]]. </p> | </blockquote> | ||
<p> | |||
If you set <var>AMPSUBZ</var> greater than 0, the X'02' bit of the <var>[[XMEMOPT parameter|XMEMOPT]]</var> parameter (the default), must also be set. </p> | |||
<p> | |||
For more information about zIIP processing, refer to [[Performance monitoring and tuning#Offloading Model 204 work to zIIP processors|Offloading Model 204 work to zIIP processors]]. </p> | |||
[[Category:System parameters]] | [[Category:System parameters]] | ||
[[Category:Parameters]] | [[Category:Parameters]] | ||
Latest revision as of 17:48, 27 February 2017
Number of active zIIP eligible subtasks
Summary
- Default value
- None
- Parameter type
- System
- Where set
- On User 0's parameter line or reset by system manager
- Related products
- All
- Introduced
- Model 204 V7.4
Description
This parameter applies to z/OS only.
On a z/OS system, Model 204 zIIP support enables you to offload Model 204 work from regular processors to zIIP processors. AMPSUBZ specifies the number of active zIIP subtasks.
The value of AMPSUBZ must be less than or equal to the value of the NMPSUBZ parameter, which determines the number of zIIP subtasks attached during initialization.
Note: MP subtasks and zIIP subtasks may be used together. Therefore, AMPSUBS, NMPSUBS, AMPSUBZ and NMPSUBZ can all be greater than zero. However, to avoid unnecessary overhead:
- Do not set AMPSUBS greater than the number of central processors actually available.
- Do not set AMPSUBZ greater than the number of zIIP processors actually available.
If you set AMPSUBZ greater than 0, the X'02' bit of the XMEMOPT parameter (the default), must also be set.
For more information about zIIP processing, refer to Offloading Model 204 work to zIIP processors.