MAXSIMIO parameter: Difference between revisions

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<dt>Default value
<dt>Default value
<dd>
<dd>
<p>32 * (<var>[[NSUBTKS_parameter|NSUBTKS]]</var>+<var>[[NSERVS_parameter|NSERVS</var>), if using IOS Branch Entry ([[XMEMOPT parameter|XMEMOPT]]=2)</p>
<p>
<p>(32*(NSUBTKS+NSERVS))+LDKBMWND, if not using IOS Branch Entry</p>
<code>32 * (<var>[[NSUBTKS parameter|NSUBTKS]]</var>+<var>[[NSERVS parameter|NSERVS]]</var>)</code>, if using IOS Branch Entry (<code>[[XMEMOPT parameter|XMEMOPT]]=2</code>)</p>
<p>
<code>(32*(NSUBTKS+NSERVS))+<var>[[LDKBMWND_parameter|LDKBMWND]]</var></code>, if not using IOS Branch Entry</p>
<dt>Parameter type
<dt>Parameter type
<dd>System
<dd>System
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==Description==
==Description==
Limits DBIDs when using IOS Branch Entry.  
Limits DBIDs when using [[IOS Branch Entry]].  
 
==Usage==
During initialization, Model&nbsp;204 calculates a default number of Disk Buffer I/O control blocks (DBIDs). If you are using IOS Branch Entry, this default number may be unnecessarily high. Use the <var>MAXSIMIO</var> parameter to allocate a smaller number of DBIDs.
<p>
Using a lower <var>MAXSIMIO</var> value when you are also using IOS Branch Entry limits the number of DBIDs allocated and results in storage savings. If you are not using IOS Branch Entry, an explicit <var>MAXSIMIO</var> setting is ignored and the value calculated by Model&nbsp;204 is used instead.</p>
 
[[Category:System parameters]]
[[Category:System parameters]]
[[Category:Parameters]]
[[Category:Parameters]]

Latest revision as of 20:49, 6 April 2017

Max simultaneous disk I/Os

Summary

Default value

32 * (NSUBTKS+NSERVS), if using IOS Branch Entry (XMEMOPT=2)

(32*(NSUBTKS+NSERVS))+LDKBMWND, if not using IOS Branch Entry

Parameter type
System
Where set
By system manager or on User 0's line
Related products
All
Introduced
Model 204 V7.4

Description

Limits DBIDs when using IOS Branch Entry.

Usage

During initialization, Model 204 calculates a default number of Disk Buffer I/O control blocks (DBIDs). If you are using IOS Branch Entry, this default number may be unnecessarily high. Use the MAXSIMIO parameter to allocate a smaller number of DBIDs.

Using a lower MAXSIMIO value when you are also using IOS Branch Entry limits the number of DBIDs allocated and results in storage savings. If you are not using IOS Branch Entry, an explicit MAXSIMIO setting is ignored and the value calculated by Model 204 is used instead.