CHECKPOINT command - Revision history

DCameron: /* Usage notes */

2019-02-07T15:40:37Z

Usage notes

← Older revision		Revision as of 15:40, 7 February 2019
Line 59:		Line 59:
	==Usage notes==		==Usage notes==
	<ul>		<ul>
	<li>The <var>CHECKPOINT</var> command requests that a checkpoint be performed. The <var class="product">Model 204</var> checkpoint facility provides a means of recovering a valid copy of a database in case of a system failure. The checkpoint facility operates by logging images of any changed file pages to a checkpoint data set.		<li>The <var>CHECKPOINT</var> command requests that a checkpoint be performed. The <var class="product">Model 204</var> [[Checkpoints:_Storing_before-images_of_changed_pages\|checkpoint facility]] provides a means of recovering a valid copy of a database in case of a system failure. The checkpoint facility operates by logging images of any changed file pages to a checkpoint data set.
	<p>		<p>
	When a checkpoint is performed, updating is temporarily suspended, the database is brought to a valid state, and marker records are written on the data set. If a subsequent system crash occurs, the database can be rolled back in time to its status at the time of a previous checkpoint. For a detailed explanation of checkpointing and system recovery, refer to [[Checkpoints: Storing before-images of changed pages]] and [[System and media recovery]].</p>		When a checkpoint is performed, updating is temporarily suspended, the database is brought to a valid state, and marker records are written on the data set. If a subsequent system crash occurs, the database can be rolled back in time to its status at the time of a previous checkpoint. For a detailed explanation of checkpointing and system recovery, refer to [[Checkpoints: Storing before-images of changed pages]] and [[System and media recovery]].</p>

DCameron: /* Syntax */

2019-02-07T15:29:55Z

Syntax

← Older revision		Revision as of 15:29, 7 February 2019
Line 54:		Line 54:
	</li>		</li>

	<li><var>END EXTENDED QUIESCE</var> keywords terminate an extended quiesce. This command also restarts the checkpoint pseudo subtask and file updating can resume in the Online. If the parameter <code>CPQZSECS=<i>nnnn</i></code> is specified, and neither a <code>CHECKPOINT SET EXTENDED QUIESCE</code> nor <code>CHECKPOINT UNSET EXTENDED QUIESCE</code> command is issued within <var class="term"> nnnn</var> seconds of the start of an extended quiesce, the action specified on the parameter <var>[[CPQZACTN parameter\|CPQZACTN]]</var> is initiated.</li>		<li><var>END EXTENDED QUIESCE</var> keywords terminate an extended quiesce. This command also restarts the checkpoint pseudo subtask and file updating can resume in the Online. If the parameter <code><var>[[CPQZSECS_parameter\|CPQZSECS]]</var>=<i>nnnn</i></code> is specified, and neither a <code>CHECKPOINT SET EXTENDED QUIESCE</code> nor <code>CHECKPOINT UNSET EXTENDED QUIESCE</code> command is issued within <var class="term"> nnnn</var> seconds of the start of an extended quiesce, the action specified on the parameter <var>[[CPQZACTN parameter\|CPQZACTN]]</var> is initiated.</li>
	</ul>		</ul>

DCameron: /* Syntax */

2019-02-07T15:28:26Z

Syntax

← Older revision		Revision as of 15:28, 7 February 2019
Line 40:		Line 40:
	The command is ignored if the Online is already in an extended quiesce. Issuing the command multiple times is the same as issuing it once.</p>		The command is ignored if the Online is already in an extended quiesce. Issuing the command multiple times is the same as issuing it once.</p>
	<p>		<p>
	If you define a ring stream journal that has an <code>OFFLOAD</code> data set defined, then when the extended quiesce begins, Model 204 issues internally an <~~code~~>OFFLOAD STREAM</~~code~~> command for the ring stream journal.</p></li>		If you define a ring stream journal that has an <code>OFFLOAD</code> data set defined, then when the extended quiesce begins, Model 204 issues internally an <var>[[OFFLOAD_command\|OFFLOAD STREAM]]</var> command for the ring stream journal.</p></li>

	<li><var>UNSET EXTENDED QUIESCE</var> keywords reverse the effect of the <var>SET EXTENDED QUIESCE</var> option. The command is ineffective if the:		<li><var>UNSET EXTENDED QUIESCE</var> keywords reverse the effect of the <var>SET EXTENDED QUIESCE</var> option. The command is ineffective if the:

DCameron: /* Syntax */

2019-02-07T15:23:56Z

Syntax

← Older revision		Revision as of 15:23, 7 February 2019
Line 18:		Line 18:
	<p>The setting <var>[[CPTYPE_parameter\|CPTYPE]]</var> is not used by this command.</p>		<p>The setting <var>[[CPTYPE_parameter\|CPTYPE]]</var> is not used by this command.</p>
	<p>		<p>
	Any system administrator can issue one or more forms of the command, if allowed by the setting of <var>[[CHKPRIV parameter\|CHKPRIV]]</var>, a non-resettable CCAIN parameter.</p>		Any system administrator can issue one or more forms of the command, if allowed by the setting of <var>[[CHKPRIV parameter\|CHKPRIV]]</var>, a non-resettable [[Controlling_system_operations_(CCAIN)\|CCAIN]] parameter.</p>
	<table>		<table>
	<tr class="head"><th>Setting</th> <th>System administrator can do...</th></tr>		<tr class="head"><th>Setting</th> <th>System administrator can do...</th></tr>

DCameron: /* Syntax */

2019-02-07T15:22:26Z

Syntax

← Older revision		Revision as of 15:22, 7 February 2019
Line 16:		Line 16:
	<p>A system manager can issue any form of the command.</p>		<p>A system manager can issue any form of the command.</p>

	<p>The setting <~~code~~>CPTYPE</~~code~~> is not used by this command.</p>		<p>The setting <var>[[CPTYPE_parameter\|CPTYPE]]</var> is not used by this command.</p>
	<p>		<p>
	Any system administrator can issue one or more forms of the command, if allowed by the setting of <var>[[CHKPRIV parameter\|CHKPRIV]]</var>, a non-resettable CCAIN parameter.</p>		Any system administrator can issue one or more forms of the command, if allowed by the setting of <var>[[CHKPRIV parameter\|CHKPRIV]]</var>, a non-resettable CCAIN parameter.</p>

DCameron: /* Summary */

2019-02-07T15:17:38Z

Summary

← Older revision		Revision as of 15:17, 7 February 2019
Line 2:		Line 2:
	<dl>		<dl>
	<dt>Privileges		<dt>Privileges
	<dd>Any user can issue a <var>CHECKPOINT</var> command without arguments; a system manager or the operator at the console can issue a <var>CHECKPOINT</var> command with arguments. A system administrator might be able to issue a <var>CHECKPOINT</var> command with certain arguments, dependent upon the setting of the <var>CHKPRIV</var> parameter.		<dd>Any user can issue a <var>CHECKPOINT</var> command without arguments; a system manager or the operator at the console can issue a <var>CHECKPOINT</var> command with arguments. A system administrator might be able to issue a <var>CHECKPOINT</var> command with certain arguments, dependent upon the setting of the <var>[[CHKPRIV_parameter\|CHKPRIV]]</var> parameter.
	<dt>Function		<dt>Function
	<dd>Requests that <var class="product">Model 204</var> perform a checkpoint		<dd>Requests that <var class="product">Model 204</var> perform a checkpoint

ELowell at 16:09, 22 March 2017

2017-03-22T16:09:51Z

← Older revision		Revision as of 16:09, 22 March 2017
Line 80:		Line 80:
	[[Category: System administrator commands]]		[[Category: System administrator commands]]
	[[Category: System manager commands]]		[[Category: System manager commands]]
	[[Category: ~~General user~~ commands]]		[[Category: User commands]]
	[[Category:Commands]]		[[Category:Commands]]

JAL: /* Usage notes */

2014-11-14T18:46:15Z

Usage notes

← Older revision		Revision as of 18:46, 14 November 2014
Line 58:		Line 58:

	==Usage notes==		==Usage notes==
	<p>		<ul>
	The <var>CHECKPOINT</var> command requests that a checkpoint be performed. The <var class="product">Model 204</var> checkpoint facility provides a means of recovering a valid copy of a database in case of a system failure. The checkpoint facility operates by logging images of any changed file pages to a checkpoint data set. ~~</p>~~		<li>The <var>CHECKPOINT</var> command requests that a checkpoint be performed. The <var class="product">Model 204</var> checkpoint facility provides a means of recovering a valid copy of a database in case of a system failure. The checkpoint facility operates by logging images of any changed file pages to a checkpoint data set.
	<p>		<p>
	When a checkpoint is performed, updating is temporarily suspended, the database is brought to a valid state, and marker records are written on the data set. If a subsequent system crash occurs, the database can be rolled back in time to its status at the time of a previous checkpoint. For a detailed explanation of checkpointing and system recovery, refer to [[Checkpoints: Storing before-images of changed pages]] and [[System and media recovery]].</p>		When a checkpoint is performed, updating is temporarily suspended, the database is brought to a valid state, and marker records are written on the data set. If a subsequent system crash occurs, the database can be rolled back in time to its status at the time of a previous checkpoint. For a detailed explanation of checkpointing and system recovery, refer to [[Checkpoints: Storing before-images of changed pages]] and [[System and media recovery]].</p>
Line 65:		Line 65:
	When a <var>CHECKPOINT</var> command is run, <var class="product">Model 204</var> does not close any currently open files or groups. <var class="product">Model 204</var> automatically generates a unique identifier to be associated with the checkpoint.</p>		When a <var>CHECKPOINT</var> command is run, <var class="product">Model 204</var> does not close any currently open files or groups. <var class="product">Model 204</var> automatically generates a unique identifier to be associated with the checkpoint.</p>
	<p>		<p>
	After the checkpoint has been performed successfully, <var class="product">Model 204</var> informs the operator and the audit trail of the date and time that the checkpoint was completed.</p>		After the checkpoint has been performed successfully, <var class="product">Model 204</var> informs the operator and the audit trail of the date and time that the checkpoint was completed.</p></li>
	<p>
	The security required for the <var>ABORT</var> and <var>MESSAGE</var> keywords is the same as for the <var>CHKABORT</var> and the <var>CHKMSG</var> commands.</p>		<li>The security required for the <var>ABORT</var> and <var>MESSAGE</var> keywords is the same as for the <var>CHKABORT</var> and the <var>CHKMSG</var> commands.</li>
	<p>
	When a <var>CHECKPOINT</var> command with an <var>END</var>, <var>SET</var>, or <var>UNSET</var> keyword is issued in a valid context, the following message is displayed: ~~</p>~~		<li>When a <var>CHECKPOINT</var> command with an <var>END</var>, <var>SET</var>, or <var>UNSET</var> keyword is issued in a valid context, the following message is displayed:
	<p class="code">M204.2611: CHECKPOINT SET/UNSET/END COMMAND SUCCESSFUL		<p class="code">M204.2611: CHECKPOINT SET/UNSET/END COMMAND SUCCESSFUL
	</p>		</p>
Line 75:		Line 75:
	When a <var>CHECKPOINT</var> command with a <var>SET</var>, <var>UNSET</var>, or <var>END</var> keyword is issued in an invalid context, the following message is displayed: </p>		When a <var>CHECKPOINT</var> command with a <var>SET</var>, <var>UNSET</var>, or <var>END</var> keyword is issued in an invalid context, the following message is displayed: </p>
	<p class="code">M204.2612: CHECKPOINT SET/UNSET/END COMMAND UNSUCCESSFUL - <var class="term">reason</var>		<p class="code">M204.2612: CHECKPOINT SET/UNSET/END COMMAND UNSUCCESSFUL - <var class="term">reason</var>
	</p>		</p></li>
			</ul>

	[[Category: System administrator commands]]		[[Category: System administrator commands]]

JAL at 17:22, 14 November 2014

2014-11-14T17:22:40Z

Show changes

JAL: remove Sys Man guide

2014-11-14T02:02:51Z

remove Sys Man guide

← Older revision		Revision as of 02:02, 14 November 2014
Line 12:		Line 12:
	Where:		Where:
	<ul>		<ul>
	<li>		<li>CHECKPOINT command with no arguments, CHECKPOINT TRAN, and CHECKPOINT SUBTRAN specify by default or explicitly, the type of checkpoint request. Any logged in user can issue a CHECKPOINT command with no arguments to attempt a transaction checkpoint.
	CHECKPOINT command with no arguments, CHECKPOINT TRAN, and CHECKPOINT SUBTRAN specify by default or explicitly, the type of checkpoint request. Any logged in user can issue a CHECKPOINT command with no arguments to attempt a transaction checkpoint.

	<p>A system manager can issue any form of the command.</p>		<p>A system manager can issue any form of the command.</p>

	<p>The setting CPTYPE is not used by this command.</p>		<p>The setting CPTYPE is not used by this command.</p>
			<p>
	Any system administrator can issue one or more forms of the command, if allowed by the setting of CHKPRIV, a non-resettable CCAIN parameter.		Any system administrator can issue one or more forms of the command, if allowed by the setting of CHKPRIV, a non-resettable CCAIN parameter.</p>
	<table>		<table>
	<tr><th>Setting</th> <th>System administrator can do...</th></tr>		<tr class="head"><th>Setting</th> <th>System administrator can do...</th></tr>
	<tr><td>X’01’</td> <td>TRAN and/or SUBTRAN</td></tr>		<tr><td>X’01’</td> <td>TRAN and/or SUBTRAN</td></tr>
	<tr><td>X’02’</td> <td>MESSAGE</td></tr>		<tr><td>X’02’</td> <td>MESSAGE</td></tr>
	<tr><td>X’04’</td> <td>ABORT</td></tr>		<tr><td>X’04’</td> <td>ABORT</td></tr>
	<tr><td>X’08’</td> <td>EXTENDED ~~QUIESE~~</td></tr>		<tr><td>X’08’</td> <td>EXTENDED QUIESCE</td></tr>
	</table>		</table></li>
	</li>
	<li>TRAN, the default, specifies to take only transaction checkpoints, as they were in Version 5.1 and earlier.</li>		<li>TRAN, the default, specifies to take only transaction checkpoints, as they were in Version 5.1 and earlier.</li>
	<li>SUBTRAN specifies to take transaction and sub-transaction checkpoints. See ~~the Model 204 System Manager’s Guide~~ to determine whether you should consider this option and what else is required of your set up.</li>
			<li>SUBTRAN specifies to take transaction and sub-transaction checkpoints. See [[Checkpoints: Storing before-images of changed pages#Overview of sub-transaction checkpoints\|Overview of sub-transaction checkpoints]] to determine whether you should consider this option and what else is required of your set up.</li>

	<li>ABORT keyword aborts a pending request for a checkpoint.</li>		<li>ABORT keyword aborts a pending request for a checkpoint.</li>

	<li>MESSAGE keyword displays the status of the most recent checkpoint.</li>		<li>MESSAGE keyword displays the status of the most recent checkpoint.</li>

	<li>SET EXTENDED QUIESCE keywords place the Online into an extended quiesce immediately after the next successful checkpoint. Once placed into an extended quiesce, no file updating can take place until the extended quiesce ends. The checkpoint that is taken at the end of Model 204 initialization or recovery is not available for extended quiesce processing.		<li>SET EXTENDED QUIESCE keywords place the Online into an extended quiesce immediately after the next successful checkpoint. Once placed into an extended quiesce, no file updating can take place until the extended quiesce ends. The checkpoint that is taken at the end of Model 204 initialization or recovery is not available for extended quiesce processing.

	<p>The command is ignored if the Online is already in an extended quiesce. Issuing the command multiple times is the same as issuing it once.</p>		<p>
			The command is ignored if the Online is already in an extended quiesce. Issuing the command multiple times is the same as issuing it once.</p>
			<p>
			If you define a ring stream journal that has an OFFLOAD data set defined, then when the extended quiesce begins, Model 204 issues internally an OFFLOAD STREAM command for the ring stream journal.</p></li>

	~~If you define a ring stream journal that has an OFFLOAD data set defined, then when the extended quiesce begins, Model 204 issues internally an OFFLOAD STREAM command for the ring stream journal.</li>~~
	<li>UNSET EXTENDED QUIESCE keywords reverse the effect of the SET EXTENDED QUIESCE option. The command is ineffective if the:		<li>UNSET EXTENDED QUIESCE keywords reverse the effect of the SET EXTENDED QUIESCE option. The command is ineffective if the:
	<ul>		<ul>
Line 42:		Line 47:
	<li>CHECKPOINT SET EXTENDED QUIESCE command has not been issued</li>		<li>CHECKPOINT SET EXTENDED QUIESCE command has not been issued</li>
	</ul>		</ul>
	Issuing this command multiple times is the same as issuing it once.		<p>
			Issuing this command multiple times is the same as issuing it once.</p>
	Issuing a CHECKPOINT UNSET EXTENDED QUIESCE command when the Online is not yet available for extended quiesce processing, results in the following error:		<p>
			Issuing a CHECKPOINT UNSET EXTENDED QUIESCE command when the Online is not yet available for extended quiesce processing, results in the following error: </p>
	<p class="code">M204.2612: CHECKPOINT COMMAND UNSUCCESSFUL - <var class="term">reasons</var></p>		<p class="code">M204.2612: CHECKPOINT COMMAND UNSUCCESSFUL - <var class="term">reasons</var></p>
	</li>		</li>