Wikimedia\Rdbms\LoadMonitor Class Reference

Basic DB load monitor with no external dependencies. More...

Inherits Wikimedia\Rdbms\ILoadMonitor.

Inherited by Wikimedia\Rdbms\LoadMonitorNull.

Collaboration diagram for Wikimedia\Rdbms\LoadMonitor:

Public Member Functions
	__construct (ILoadBalancer $lb, BagOStuff $srvCache, WANObjectCache $wCache, $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 $options Additional parameters include: maxConnCount: maximum number of connections before circuit breaking to kick in [default: infinity]
	scaleLoads (array &$weightByServer)
	Perform load ratio adjustment before deciding which server to use.
	setLogger (LoggerInterface $logger)
	setMockTime (&$time)
	setStatsdDataFactory (StatsdDataFactoryInterface $statsFactory)
	Sets a StatsdDataFactory instance on the object.

Protected Member Functions
	computeServerState (int $i, ?array $previousState)
	getCurrentTime ()
	getServerStates (array $serverIndexes)
	getStateFromWanCache ( $i, ?array $srvPrevState)
	makeStateKey (IStoreKeyEncoder $cache, int $i)
	newInitialServerState ()

Protected Attributes
ILoadBalancer	$lb
LoggerInterface	$logger
BagOStuff	$srvCache
StatsdDataFactoryInterface	$statsd
WANObjectCache	$wanCache

Additional Inherited Members
Public Attributes inherited from Wikimedia\Rdbms\ILoadMonitor
const	STATE_AS_OF = 'time'
const	STATE_CONN_COUNT = 'conn_count'
const	STATE_UP = 'up'

Detailed Description

Basic DB load monitor with no external dependencies.

This uses both local server and local datacenter caches for DB server state information.

Definition at line 41 of file LoadMonitor.php.

Constructor & Destructor Documentation

__construct()

Wikimedia\Rdbms\LoadMonitor::__construct	(	ILoadBalancer	$lb,
		BagOStuff	$srvCache,
		WANObjectCache	$wCache,
			$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	Additional parameters include: maxConnCount: maximum number of connections before circuit breaking to kick in [default: infinity]

Implements Wikimedia\Rdbms\ILoadMonitor.

Definition at line 73 of file LoadMonitor.php.

References Wikimedia\Rdbms\LoadMonitor\$lb, and Wikimedia\Rdbms\LoadMonitor\$srvCache.

Member Function Documentation

computeServerState()

Wikimedia\Rdbms\LoadMonitor::computeServerState ( int $i, ?array $previousState )

protected

Parameters

int	$i
array | null	$previousState

Returns

array<string,mixed>

Exceptions

DBAccessError

Definition at line 221 of file LoadMonitor.php.

References Wikimedia\Rdbms\ILoadBalancer\CONN_SILENCE_ERRORS, Wikimedia\Rdbms\ILoadBalancer\CONN_UNTRACKED_GAUGE, and Wikimedia\Rdbms\ILoadBalancer\DOMAIN_ANY.

getCurrentTime()

Wikimedia\Rdbms\LoadMonitor::getCurrentTime ( )

protected

Returns

float UNIX timestamp

Definition at line 338 of file LoadMonitor.php.

getServerStates()

Wikimedia\Rdbms\LoadMonitor::getServerStates ( array $serverIndexes )

protected

Definition at line 150 of file LoadMonitor.php.

Referenced by Wikimedia\Rdbms\LoadMonitor\scaleLoads().

getStateFromWanCache()

Wikimedia\Rdbms\LoadMonitor::getStateFromWanCache ( $i, ?array $srvPrevState )

protected

Definition at line 177 of file LoadMonitor.php.

makeStateKey()

Wikimedia\Rdbms\LoadMonitor::makeStateKey ( IStoreKeyEncoder $cache, int $i )

protected

Definition at line 204 of file LoadMonitor.php.

References Wikimedia\ObjectCache\IStoreKeyEncoder\makeGlobalKey(), and Wikimedia\Rdbms\ServerInfo\WRITER_INDEX.

newInitialServerState()

Wikimedia\Rdbms\LoadMonitor::newInitialServerState ( )

protected

Returns

array<string,mixed>

Definition at line 294 of file LoadMonitor.php.

scaleLoads()

Wikimedia\Rdbms\LoadMonitor::scaleLoads

(

array &

$weightByServer

)

Perform load ratio adjustment before deciding which server to use.

Parameters

array<int,int|float>

&$weightByServer Map of (server index => weight)

Implements Wikimedia\Rdbms\ILoadMonitor.

Reimplemented in Wikimedia\Rdbms\LoadMonitorNull.

Definition at line 96 of file LoadMonitor.php.

References Wikimedia\Rdbms\LoadMonitor\getServerStates(), and Wikimedia\Rdbms\ILoadMonitor\STATE_CONN_COUNT.

setLogger()

Wikimedia\Rdbms\LoadMonitor::setLogger

(

LoggerInterface

$logger

)

Definition at line 88 of file LoadMonitor.php.

References Wikimedia\Rdbms\LoadMonitor\$logger.

setMockTime()

Wikimedia\Rdbms\LoadMonitor::setMockTime

(

&

$time

)

Parameters

float | null

&$time

Mock UNIX timestamp for testing

Definition at line 346 of file LoadMonitor.php.

setStatsdDataFactory()

Wikimedia\Rdbms\LoadMonitor::setStatsdDataFactory

(

StatsdDataFactoryInterface

$statsFactory

)

Sets a StatsdDataFactory instance on the object.

Parameters

StatsdDataFactoryInterface

$statsFactory

Returns

null

Implements Wikimedia\Stats\StatsdAwareInterface.

Definition at line 92 of file LoadMonitor.php.

Member Data Documentation

$lb

ILoadBalancer Wikimedia\Rdbms\LoadMonitor::$lb

protected

Definition at line 43 of file LoadMonitor.php.

Referenced by Wikimedia\Rdbms\LoadMonitor\__construct().

$logger

LoggerInterface Wikimedia\Rdbms\LoadMonitor::$logger

protected

Definition at line 49 of file LoadMonitor.php.

Referenced by Wikimedia\Rdbms\LoadMonitor\setLogger().

$srvCache

BagOStuff Wikimedia\Rdbms\LoadMonitor::$srvCache

protected

Definition at line 45 of file LoadMonitor.php.

Referenced by Wikimedia\Rdbms\LoadMonitor\__construct().

$statsd

StatsdDataFactoryInterface Wikimedia\Rdbms\LoadMonitor::$statsd

protected

Definition at line 51 of file LoadMonitor.php.

$wanCache

WANObjectCache Wikimedia\Rdbms\LoadMonitor::$wanCache

protected

Definition at line 47 of file LoadMonitor.php.

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

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