NUMBUFG parameter: Difference between revisions
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<ul> | <ul> | ||
<li>Prior to version 7.7 of Model 204: | <li>Prior to version 7.7 of Model 204: | ||
<p><var>NUMBUFG</var> specifies the number of buffer pool buffers built ATB, and the number of buffer pool buffers built BTB is based on the setting of <var>MINBUF</var>, <var>MAXBUF</var>, and <var>SPCORE</var>.</p></li> | <p><var>NUMBUFG</var> specifies the number of buffer pool buffers built ATB, and the number of buffer pool buffers built BTB is based on the setting of <var>[[MINBUF parameter|MINBUF]]</var>, <var>[[MAXBUF parameter|MAXBUF]]</var>, and <var>[[SPCORE parameter|SPCORE]]</var>.</p></li> | ||
<li>As of version 7.7: | <li>As of version 7.7: | ||
<p>If <var>NUMBUFG</var> is specified, no buffer pool buffers are built BTB; all buffers are ATB. The <var>MINBUF</var> parameter is automatically reset to 0, and <var>MAXBUF</var> and <var>SPCORE</var> are ignored. </p></li> | <p>If <var>NUMBUFG</var> is specified, no buffer pool buffers are built BTB; all buffers are ATB. The <var>MINBUF</var> parameter is automatically reset to 0, and <var>MAXBUF</var> and <var>SPCORE</var> are ignored. </p> | ||
</li> | |||
</ul> | </ul> | ||
<p> | <p> | ||
The maximum number of buffers is <code>2**31/3</code>, or <code>715,827,882</code>, which limits buffer pools to 4.2 terabytes or less.</p> | The maximum number of buffers is <code>2**31/3</code>, or <code>715,827,882</code>, which limits buffer pools to 4.2 terabytes or less.</p> | ||
<p> | <p> | ||
For | The minimum number of ATB buffers is: </p> | ||
<p class="code">[[NLRUQG parameter|NLRUQG]] * (([[NSERVS parameter|NSERVS]] + [[NSUBTKS parameter|NSUBTKS]]) * [[MAXOBUF parameter|MAXOBUF]] + 15) | |||
</p> | |||
<p> | |||
If you set <var>NUMBUFG</var> to a lower value, it is reset to the calculated value.</p> | |||
<p> | |||
For more information about setting <var>NUMBUFG</var>, see [[Defining the runtime environment (CCAIN)#Managing ATB storage with NUMBUFG|Managing ATB storage with NUMBUFG]]. </p> | |||
[[Category:System parameters]] | [[Category:System parameters]] | ||
[[Category:Parameters]] | [[Category:Parameters]] | ||
Revision as of 22:54, 18 August 2016
Number of above-the-bar buffers
Summary
- Default value
- 0
- Parameter type
- System
- Where set
- Not resettable
- Related products
- All
- Introduced
- Model 204 V7.1
Description
Allocate this number of buffer pool buffers above the bar (ATB).
- Prior to version 7.7 of Model 204:
NUMBUFG specifies the number of buffer pool buffers built ATB, and the number of buffer pool buffers built BTB is based on the setting of MINBUF, MAXBUF, and SPCORE.
- As of version 7.7:
If NUMBUFG is specified, no buffer pool buffers are built BTB; all buffers are ATB. The MINBUF parameter is automatically reset to 0, and MAXBUF and SPCORE are ignored.
The maximum number of buffers is 2**31/3, or 715,827,882, which limits buffer pools to 4.2 terabytes or less.
The minimum number of ATB buffers is:
NLRUQG * ((NSERVS + NSUBTKS) * MAXOBUF + 15)
If you set NUMBUFG to a lower value, it is reset to the calculated value.
For more information about setting NUMBUFG, see Managing ATB storage with NUMBUFG.