RCVOPT parameter - Revision history

JAL: misc formatting

2017-05-22T16:20:30Z

misc formatting

← Older revision		Revision as of 16:20, 22 May 2017
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	<tr><th><var>X'01'</var></th>		<tr><th><var>X'01'</var></th>
	<td~~><var~~>[[Checkpoints:~~_Storing_before~~-~~images_of_changed_pages~~\|Checkpoints]]~~</var>~~ are taken.</td></tr>		<td>[[Checkpoints: Storing before-images of changed pages\|Checkpoints]] are taken.</td></tr>

	<tr><th><var>X'08'</var></th>		<tr><th><var>X'08'</var></th>
	<td~~><var~~>[[~~RESTART_command~~#~~Rolling_back_and_rolling_forward~~\|Roll forward]]~~</var>~~ information is logged into the journal stream.</td></tr>		<td>[[RESTART command#Rolling back and rolling forward\|Roll forward]] information is logged into the journal stream.</td></tr>

	<tr><th><var>X'20'</var></th>		<tr><th><var>X'20'</var></th>
	<td>Do not flush the dirty pages in a file that does not do pre-imaging (<var>[[FRCVOPT parameter\|FRCVOPT]]</var> X'20' set) during a ~~<var>~~[[Checkpoints:~~_Storing_before~~-~~images_of_changed_pages~~#~~Overview_of_sub~~-~~transaction_checkpoints~~\|subtransaction checkpoint]]~~</var>~~. This bit has an effect in Model 204 7.6 and later; for V7.5, it requires an appropriate maintenance zap.		<td>Do not flush the dirty pages in a file that does not do pre-imaging (<var>[[FRCVOPT parameter\|FRCVOPT]]</var> X'20' set) during a [[Checkpoints: Storing before-images of changed pages#Overview of sub-transaction checkpoints\|subtransaction checkpoint]]. This bit has an effect in Model 204 7.6 and later; for V7.5, it requires an appropriate maintenance zap.
	<p>		<p>
	One use of this setting is to set <var>FRCVOPT</var> X'20' for a file that holds <var class="product">[[SirFact]]</var> dumps, which can get quite large. This bit prevents a large <var class="product">SirFact</var> dump from causing a subtransaction checkpoint to take a very long time. While this might result in a <var class="product">SirFact</var> dump being lost if the system crashes, such a loss is probably not that critical, so its risk is probably well worth the benefit of faster subtransaction checkpoints.</p></td></tr>		One use of this setting is to set <var>FRCVOPT</var> X'20' for a file that holds <var class="product">[[SirFact]]</var> dumps, which can get quite large. This bit prevents a large <var class="product">SirFact</var> dump from causing a subtransaction checkpoint to take a very long time. While this might result in a <var class="product">SirFact</var> dump being lost if the system crashes, such a loss is probably not that critical, so its risk is probably well worth the benefit of faster subtransaction checkpoints.</p></td></tr>

DCameron: /* Description */

2017-05-18T14:10:30Z

Description

← Older revision		Revision as of 14:10, 18 May 2017
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	<tr><th><var>X'20'</var></th>		<tr><th><var>X'20'</var></th>
	<td>Do not flush the dirty pages in a file that does not do pre-imaging (<var>[[FRCVOPT parameter\|FRCVOPT]]</var> X'20' set) during a subtransaction checkpoint. This bit has an effect in Model 204 7.6 and later; for V7.5, it requires an appropriate maintenance zap.		<td>Do not flush the dirty pages in a file that does not do pre-imaging (<var>[[FRCVOPT parameter\|FRCVOPT]]</var> X'20' set) during a <var>[[Checkpoints:_Storing_before-images_of_changed_pages#Overview_of_sub-transaction_checkpoints\|subtransaction checkpoint]]</var>. This bit has an effect in Model 204 7.6 and later; for V7.5, it requires an appropriate maintenance zap.
	<p>		<p>
	One use of this setting is to set <var>FRCVOPT</var> X'20' for a file that holds <var class="product">[[SirFact]]</var> dumps, which can get quite large. This bit prevents a large <var class="product">SirFact</var> dump from causing a subtransaction checkpoint to take a very long time. While this might result in a <var class="product">SirFact</var> dump being lost if the system crashes, such a loss is probably not that critical, so its risk is probably well worth the benefit of faster subtransaction checkpoints.</p></td></tr>		One use of this setting is to set <var>FRCVOPT</var> X'20' for a file that holds <var class="product">[[SirFact]]</var> dumps, which can get quite large. This bit prevents a large <var class="product">SirFact</var> dump from causing a subtransaction checkpoint to take a very long time. While this might result in a <var class="product">SirFact</var> dump being lost if the system crashes, such a loss is probably not that critical, so its risk is probably well worth the benefit of faster subtransaction checkpoints.</p></td></tr>

DCameron: /* Description */

2017-05-18T14:04:31Z

Description

← Older revision		Revision as of 14:04, 18 May 2017
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	<tr><th><var>X'01'</var></th>		<tr><th><var>X'01'</var></th>
	<td>Checkpoints are taken.</td></tr>		<td><var>[[Checkpoints:_Storing_before-images_of_changed_pages\|Checkpoints]]</var> are taken.</td></tr>

	<tr><th><var>X'08'</var></th>		<tr><th><var>X'08'</var></th>

DCameron: Undo revision 102998 by DCameron (talk)

2017-05-18T14:02:11Z

Undo revision 102998 by DCameron (talk)

← Older revision		Revision as of 14:02, 18 May 2017
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	<tr><th><var>X'01'</var></th>		<tr><th><var>X'01'</var></th>
	<td>~~<var>[[~~Checkpoints~~:_Storing_before-images_of_changed_pages\|Checkpoints]]<var>~~ are taken.</td></tr>		<td>Checkpoints are taken.</td></tr>

	<tr><th><var>X'08'</var></th>		<tr><th><var>X'08'</var></th>

DCameron: /* Description */

2017-05-18T13:22:52Z

Description

← Older revision		Revision as of 13:22, 18 May 2017
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	<tr><th><var>X'08'</var></th>		<tr><th><var>X'08'</var></th>
	<td>Roll forward information is logged into the journal stream.</td></tr>		<td><var>[[RESTART_command#Rolling_back_and_rolling_forward\|Roll forward]]</var> information is logged into the journal stream.</td></tr>

	<tr><th><var>X'20'</var></th>		<tr><th><var>X'20'</var></th>

DCameron: /* Description */

2017-05-18T13:20:38Z

Description

← Older revision		Revision as of 13:20, 18 May 2017
Line 22:		Line 22:

	<tr><th><var>X'01'</var></th>		<tr><th><var>X'01'</var></th>
	<td>Checkpoints are taken.</td></tr>		<td><var>[[Checkpoints:_Storing_before-images_of_changed_pages\|Checkpoints]]<var> are taken.</td></tr>

	<tr><th><var>X'08'</var></th>		<tr><th><var>X'08'</var></th>

DCameron: /* Summary */

2017-05-18T12:56:32Z

Summary

← Older revision		Revision as of 12:56, 18 May 2017
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	<dd>All		<dd>All
	<dt>Introduced		<dt>Introduced
	<dd><var class="product">Model 204 V6.1</var> or earlier		<dd><var class="product">Model 204 V2.1</var> or earlier
	</dl>		</dl>

JAL: mention 7.5 zap

2015-04-23T19:52:35Z

mention 7.5 zap

← Older revision		Revision as of 19:52, 23 April 2015
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	<tr><th><var>X'20'</var></th>		<tr><th><var>X'20'</var></th>
	<td>Do not flush the dirty pages in a file that does not do pre-imaging (<var>[[FRCVOPT parameter\|FRCVOPT]]</var> X'20' set) during a subtransaction checkpoint. This bit ~~only~~ has an effect in Model 204 7.6 and later.		<td>Do not flush the dirty pages in a file that does not do pre-imaging (<var>[[FRCVOPT parameter\|FRCVOPT]]</var> X'20' set) during a subtransaction checkpoint. This bit has an effect in Model 204 7.6 and later; for V7.5, it requires an appropriate maintenance zap.
	<p>		<p>
	One use of this setting is to set <var>FRCVOPT</var> X'20' for a file that holds <var class="product">[[SirFact]]</var> dumps, which can get quite large. This ~~will prevent~~ a large <var class="product">SirFact</var> dump from causing a subtransaction checkpoint to take a very long time. While this might result in a <var class="product">SirFact</var> dump being lost if the system crashes, such a loss is probably not that critical, so its risk is probably well worth the benefit of faster subtransaction checkpoints.</p></td></tr>		One use of this setting is to set <var>FRCVOPT</var> X'20' for a file that holds <var class="product">[[SirFact]]</var> dumps, which can get quite large. This bit prevents a large <var class="product">SirFact</var> dump from causing a subtransaction checkpoint to take a very long time. While this might result in a <var class="product">SirFact</var> dump being lost if the system crashes, such a loss is probably not that critical, so its risk is probably well worth the benefit of faster subtransaction checkpoints.</p></td></tr>
	</table>		</table>

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

JAL: misc cleanup

2015-04-08T15:03:33Z

misc cleanup

← Older revision		Revision as of 15:03, 8 April 2015
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	<dd><var class="product">Model 204 V6.1</var> or earlier		<dd><var class="product">Model 204 V6.1</var> or earlier
	</dl>		</dl>

	==Description==		==Description==
	<~~p>The recovery options</~~p>		<p>
	~~<p>~~Valid settings of RCVOPT are (options can be summed):</p>		Valid settings of <var>RCVOPT</var> are (options can be summed):</p>
	<table>		<table>
	<tr><th>Setting</th><th>Meaning</th></tr>		<tr class="head"><th>Setting</th>
	<tr><th ~~align="right"~~><var>X'01'</var></th><td>Checkpoints are taken.</td></tr>		<th>Meaning</th></tr>
	<tr><th ~~align="right"~~><var>X'08'</var></th><td>Roll forward information is logged into the journal stream.</td></tr>
	<tr><th ~~align="right"~~><var>X'20'</var></th><td>Do not flush the dirty pages in a file that does not do pre-imaging ([[FRCVOPT parameter\|FRCVOPT]] X'20' set) during a ~~subtransation~~ checkpoint. This bit only has an effect in Model 204 7.6 and later. One use of this setting ~~would be~~ to set FRCVOPT X'20' in a file ~~used to hold~~ SirFact dumps which can get quite large. This ~~would~~ prevent a large SirFact dump from causing a subtransaction checkpoint to take a very long time. While this ~~could~~ result in a SirFact dump being lost if the system crashes, ~~this~~ is probably not that ~~big a deal~~ so ~~the~~ risk is probably well worth the benefit of faster subtransaction checkpoints.</td></tr>		<tr><th><var>X'01'</var></th>
			<td>Checkpoints are taken.</td></tr>

			<tr><th><var>X'08'</var></th>
			<td>Roll forward information is logged into the journal stream.</td></tr>

			<tr><th><var>X'20'</var></th>
			<td>Do not flush the dirty pages in a file that does not do pre-imaging (<var>[[FRCVOPT parameter\|FRCVOPT]]</var> X'20' set) during a subtransaction checkpoint. This bit only has an effect in Model 204 7.6 and later.
			<p>
			One use of this setting is to set <var>FRCVOPT</var> X'20' for a file that holds <var class="product">[[SirFact]]</var> dumps, which can get quite large. This will prevent a large <var class="product">SirFact</var> dump from causing a subtransaction checkpoint to take a very long time. While this might result in a <var class="product">SirFact</var> dump being lost if the system crashes, such a loss is probably not that critical, so its risk is probably well worth the benefit of faster subtransaction checkpoints.</p></td></tr>
	</table>		</table>

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

Alex: /* Description */

2015-04-07T21:21:19Z

Description

← Older revision		Revision as of 21:21, 7 April 2015
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	<table>		<table>
	<tr><th>Setting</th><th>Meaning</th></tr>		<tr><th>Setting</th><th>Meaning</th></tr>
	<tr><th align="right"><var>1</var></th><td>Checkpoints are taken.</td></tr>		<tr><th align="right"><var>X'01'</var></th><td>Checkpoints are taken.</td></tr>
	<tr><th align="right"><var>8</var></th><td>Roll forward information is logged into the journal stream.</td></tr>		<tr><th align="right"><var>X'08'</var></th><td>Roll forward information is logged into the journal stream.</td></tr>
			<tr><th align="right"><var>X'20'</var></th><td>Do not flush the dirty pages in a file that does not do pre-imaging ([[FRCVOPT parameter\|FRCVOPT]] X'20' set) during a subtransation checkpoint. This bit only has an effect in Model 204 7.6 and later. One use of this setting would be to set FRCVOPT X'20' in a file used to hold SirFact dumps which can get quite large. This would prevent a large SirFact dump from causing a subtransaction checkpoint to take a very long time. While this could result in a SirFact dump being lost if the system crashes, this is probably not that big a deal so the risk is probably well worth the benefit of faster subtransaction checkpoints.</td></tr>
	</table>		</table>
	[[Category:System parameters]]		[[Category:System parameters]]
	[[Category:Parameters]]		[[Category:Parameters]]