AGESCAN parameter: Difference between revisions
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==Summary== | ==Summary== | ||
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==Description== | ==Description== | ||
<p>The allowable real-time interval in milliseconds between scans of wait queues performed by the aging logic</p> | <p>The allowable real-time interval in milliseconds between scans of wait queues performed by the aging logic</p> | ||
<p>AGESCAN controls how fast the scheduler notices that a particular user should be aged. Setting this parameter to 0 deactivates queue aging, in which case AGEINCR, AGEINTVL, AGESLICE, PRIOMAX, and SLICEMAX are ignored. </p> | <p>AGESCAN controls how fast the scheduler notices that a particular user should be aged. Setting this parameter to 0 deactivates queue aging, in which case <var>[[AGEINCR_parameter|AGEINCR]]</var>, <var>[[AGEINTVL_parameter|AGEINTVL]]</var>, <var>[[AGESLICE_parameter|AGESLICE]]</var>, <var>[[PRIOMAX_parameter|PRIOMAX]]</var>, and <var>[[SLICEMAX_parameter|SLICEMAX]]</var> are ignored. </p> | ||
<p>Increasing AGESCAN increases the time it takes the scheduler to notice that a user has waited long enough to be aged. However, it also reduces scheduler overhead. </p> | <p>Increasing AGESCAN increases the time it takes the scheduler to notice that a user has waited long enough to be aged. However, it also reduces scheduler overhead. </p> | ||
<p>Avoid small nonzero values, because the smaller values require more frequent checking, causing an increase in scheduler overhead. Do not set AGESCAN to a nonzero value less than AGEINTVL. </p> | <p>Avoid small nonzero values, because the smaller values require more frequent checking, causing an increase in scheduler overhead. Do not set AGESCAN to a nonzero value less than AGEINTVL. </p> | ||
<p class="note"><b>Note:</b> The <var class="product">Model 204</var> aging facility increases scheduler overhead and is of limited use in XA environments with many servers and more than four megabytes of virtual storage for <var class="product">Model 204</var>.</p> | <p class="note"><b>Note:</b> The <var class="product">Model 204</var> aging facility increases scheduler overhead and is of limited use in XA environments with many servers and more than four megabytes of virtual storage for <var class="product">Model 204</var>.</p> | ||
[[Category:Scheduler parameters]] | [[Category:Scheduler parameters]] | ||
[[Category: System | [[Category:System parameters]] | ||
[[Category:Parameters]] | [[Category:Parameters]] | ||
Latest revision as of 12:49, 9 October 2014
Age scan interval
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 V6.1 or earlier
Description
The allowable real-time interval in milliseconds between scans of wait queues performed by the aging logic
AGESCAN controls how fast the scheduler notices that a particular user should be aged. Setting this parameter to 0 deactivates queue aging, in which case AGEINCR, AGEINTVL, AGESLICE, PRIOMAX, and SLICEMAX are ignored.
Increasing AGESCAN increases the time it takes the scheduler to notice that a user has waited long enough to be aged. However, it also reduces scheduler overhead.
Avoid small nonzero values, because the smaller values require more frequent checking, causing an increase in scheduler overhead. Do not set AGESCAN to a nonzero value less than AGEINTVL.
Note: The Model 204 aging facility increases scheduler overhead and is of limited use in XA environments with many servers and more than four megabytes of virtual storage for Model 204.