APSYPAGE parameter: Difference between revisions

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<p>
<p>
<var>APSYPAGE</var> was implemented to take advantage of the <code>MVPG</code> machine language instruction which moved an entire hardware page (4K) with a single instruction and which, at the time, had significantly better performance than the stream-oriented moves used by standard APSY load. However, recent hardware models actually seem to have better performance for the stream-oriented moves.</p>
<var>APSYPAGE</var> was implemented to take advantage of the <code>MVPG</code> machine language instruction which moved an entire hardware page (4K) with a single instruction and which, at the time, had significantly better performance than the stream-oriented moves used by standard APSY load. However, recent hardware models actually seem to have better performance for the stream-oriented moves.</p>
<p>Therefore, it is now recommended that customers who have been using the <var>APSYPAGE</var> parameter <var class="term">disable the APSYPAGE feature</var> by setting <var>APSYPAGE</var> to 0. Then set the <var>[[RESPAGE parameter|RESPAGE]]</var> parameter to the former value of APSYPAGE.</p>
<p>Therefore, it is now recommended that customers who have been using the <var>APSYPAGE</var> parameter <var class="term">disable the APSYPAGE feature</var> by setting <var>APSYPAGE</var> to 0.</p>  


The units for both <var>RESPAGE</var> and <var>APSYPAGE</var> are 4096 (hardware page size) bytes.
<p>Instead of APSYPAGE, you can use either of the following:</p>
 
<ul>
Alternatively, you can use <var>[[TEMPPAGE parameter|TEMPPAGE]]</var> instead of APSYPAGE. TEMPPAGE units are 6184 bytes, so you would use the APSYPAGE value, divided by 1.5.
<li>The <var>[[RESPAGE parameter|RESPAGE]]</var> parameter (recommended for performance). Set <var>RESPAGE</var> to the former value of APSYPAGE. Both <var>RESPAGE</var> and <var>APSYPAGE</var> are 4096 (hardware page size) bytes.</li>
<li>
The <var>[[TEMPPAGE parameter|TEMPPAGE]]</var> parameter. TEMPPAGE pages are bigger so fewer are needed; divide the former APSYPAGE value by 1.5 before adding to TEMPPAGE. TEMPPAGE pages are 6184 bytes, with 6144 used to hold data and 40 bytes as page trailers.</li>
</ul>


[[Category:System parameters]]
[[Category:System parameters]]
[[Category:Parameters]]
[[Category:Parameters]]

Revision as of 17:27, 14 January 2016

APSYPAGE is obsolete as of 7.6

Summary

Default value
0
Parameter type
System
Where set
On User 0's parameter line
Related products
All
Introduced
Model 204 V5.1

Description

Activates the APSY Precompiled Procedures in Storage feature by specifying a number of 4K operating system pages.

For IBM z/OS systems only.

APSYPAGE was implemented to take advantage of the MVPG machine language instruction which moved an entire hardware page (4K) with a single instruction and which, at the time, had significantly better performance than the stream-oriented moves used by standard APSY load. However, recent hardware models actually seem to have better performance for the stream-oriented moves.

Therefore, it is now recommended that customers who have been using the APSYPAGE parameter disable the APSYPAGE feature by setting APSYPAGE to 0.

Instead of APSYPAGE, you can use either of the following:

  • The RESPAGE parameter (recommended for performance). Set RESPAGE to the former value of APSYPAGE. Both RESPAGE and APSYPAGE are 4096 (hardware page size) bytes.
  • The TEMPPAGE parameter. TEMPPAGE pages are bigger so fewer are needed; divide the former APSYPAGE value by 1.5 before adding to TEMPPAGE. TEMPPAGE pages are 6184 bytes, with 6144 used to hold data and 40 bytes as page trailers.