markdown/admin/maintain.html.md.erb - hawq-docs - Git at Google

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 title: Routine System Maintenance Tasks
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 ## <a id="overview-topic"></a>Overview

 To keep a HAWQ system running efficiently, the database must be regularly cleared of expired data and the table statistics must be updated so that the query optimizer has accurate information.

 HAWQ requires that certain tasks be performed regularly to achieve optimal performance. The tasks discussed here are required, but database administrators can automate them using standard UNIX tools such as `cron` scripts. An administrator sets up the appropriate scripts and checks that they execute successfully. See [Recommended Monitoring and Maintenance Tasks](RecommendedMonitoringTasks.html) for additional suggested maintenance activities you can implement to keep your HAWQ system running optimally.

 ## <a id="topic10"></a>Log File Maintenance

 Every database instance in HAWQ \(master and segments\) runs a PostgreSQL database server with its own server log file. For information about managing these log files, refer to [HAWQ Database Server Log Files](logfiles.html#topic28).

 Log files are also generated when you invoke HAWQ management utilities such as `hawq start` and `gpfdist`. [Management Utility Log Files](logfiles.html#mgmtutil_log) provides information and maintenance strategies for these log files.
	---
	title: Routine System Maintenance Tasks
	---

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	## <a id="overview-topic"></a>Overview

	To keep a HAWQ system running efficiently, the database must be regularly cleared of expired data and the table statistics must be updated so that the query optimizer has accurate information.

	HAWQ requires that certain tasks be performed regularly to achieve optimal performance. The tasks discussed here are required, but database administrators can automate them using standard UNIX tools such as `cron` scripts. An administrator sets up the appropriate scripts and checks that they execute successfully. See [Recommended Monitoring and Maintenance Tasks](RecommendedMonitoringTasks.html) for additional suggested maintenance activities you can implement to keep your HAWQ system running optimally.

	## <a id="topic10"></a>Log File Maintenance

	Every database instance in HAWQ \(master and segments\) runs a PostgreSQL database server with its own server log file. For information about managing these log files, refer to [HAWQ Database Server Log Files](logfiles.html#topic28).

	Log files are also generated when you invoke HAWQ management utilities such as `hawq start` and `gpfdist`. [Management Utility Log Files](logfiles.html#mgmtutil_log) provides information and maintenance strategies for these log files.