Wikimedia\Rdbms\ILoadMonitor Interface Reference

An interface for database load monitoring. More...

Inheritance diagram for Wikimedia\Rdbms\ILoadMonitor:

Collaboration diagram for Wikimedia\Rdbms\ILoadMonitor:

Public Member Functions
	__construct (ILoadBalancer $lb, BagOStuff $sCache, WANObjectCache $wCache, array $options=[])
	Construct a new LoadMonitor with a given LoadBalancer parent. More...
	getLagTimes (array $serverIndexes, $domain)
	Get an estimate of replication lag (in seconds) for each server. More...
	scaleLoads (array &$weightByServer, $domain)
	Perform load ratio adjustment before deciding which server to use. More...

Detailed Description

An interface for database load monitoring.

Definition at line 35 of file ILoadMonitor.php.

Constructor & Destructor Documentation

__construct()

Wikimedia\Rdbms\ILoadMonitor::__construct	(	ILoadBalancer	$lb,
		BagOStuff	$sCache,
		WANObjectCache	$wCache,
		array	$options = []
	)

Construct a new LoadMonitor with a given LoadBalancer parent.

Parameters

ILoadBalancer	$lb	LoadBalancer this instance serves
BagOStuff	$sCache	Local server memory cache
WANObjectCache	$wCache	Local cluster memory cache
array	$options	Options map

Implemented in Wikimedia\Rdbms\LoadMonitor, Wikimedia\Rdbms\LoadMonitorMySQL, and Wikimedia\Rdbms\LoadMonitorNull.

Member Function Documentation

getLagTimes()

Wikimedia\Rdbms\ILoadMonitor::getLagTimes	(	array	$serverIndexes,
			$domain
	)

Get an estimate of replication lag (in seconds) for each server.

Values may be "false" if replication is too broken to estimate

Parameters

int[]	$serverIndexes
string	$domain

Returns

array Map of (server index => float|int|bool)

Implemented in Wikimedia\Rdbms\LoadMonitor, and Wikimedia\Rdbms\LoadMonitorNull.

scaleLoads()

Wikimedia\Rdbms\ILoadMonitor::scaleLoads	(	array &	$weightByServer,
			$domain
	)

Perform load ratio adjustment before deciding which server to use.

Parameters

int[]	&$weightByServer	Map of (server index => float weight)
string | bool	$domain

Implemented in Wikimedia\Rdbms\LoadMonitor, and Wikimedia\Rdbms\LoadMonitorNull.

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The documentation for this interface was generated from the following file:

• includes/libs/rdbms/loadmonitor/ILoadMonitor.php