A multi-database, multi-master factory for Wikimedia and similar installations. More...

Inheritance diagram for LBFactoryMulti:

Collaboration diagram for LBFactoryMulti:

Public Member Functions
	__construct (array $conf)

	forEachLB ($callback, array $params=[])
	Execute a function for each tracked load balancer The callback is called with the load balancer as the first parameter, and $params passed as the subsequent parameters. More...

	getExternalLB ($cluster)
	Get a cached (tracked) load balancer for external storage. More...

	getMainLB ($domain=false)

	newExternalLB ($cluster)
	Create a new load balancer for external storage. More...

	newMainLB ($domain=false)

Public Member Functions inherited from LBFactory
	__construct (array $conf)
	Construct a manager of ILoadBalancer objects. More...

	__destruct ()

	appendPreShutdownTimeAsQuery ($url, $time)
	Append ?cpPosTime parameter to a URL for ChronologyProtector purposes if needed. More...

	beginMasterChanges ($fname=__METHOD__)
	Flush any master transaction snapshots and set DBO_TRX (if DBO_DEFAULT is set) More...

	closeAll ()
	Close all open database connections on all open load balancers. More...

	commitAll ($fname=__METHOD__, array $options=[])
	Commit open transactions on all connections. More...

	commitAndWaitForReplication ($fname, $ticket, array $opts=[])
	Convenience method for safely running commitMasterChanges()/waitForReplication() More...

	commitMasterChanges ($fname=__METHOD__, array $options=[])
	Commit changes on all master connections. More...

	destroy ()
	Disables all load balancers. More...

	disableChronologyProtection ()
	Disable the ChronologyProtector for all load balancers. More...

	flushReplicaSnapshots ($fname=__METHOD__)
	Commit all replica DB transactions so as to flush any REPEATABLE-READ or SSI snapshot. More...

	getChronologyProtectorTouched ($dbName)

	getEmptyTransactionTicket ($fname)
	Get a token asserting that no transaction writes are active. More...

	getExternalLB ($cluster)

	getMainLB ($domain=false)

	hasMasterChanges ()
	Determine if any master connection has pending changes. More...

	hasOrMadeRecentMasterChanges ($age=null)
	Determine if any master connection has pending/written changes from this request. More...

	laggedReplicaUsed ()
	Detemine if any lagged replica DB connection was used. More...

	newExternalLB ($cluster)

	newMainLB ($domain=false)

	rollbackMasterChanges ($fname=__METHOD__)
	Rollback changes on all master connections. More...

	setAgentName ($agent)

	setDomainPrefix ($prefix)
	Set a new table prefix for the existing local domain ID for testing. More...

	setRequestInfo (array $info)

	setWaitForReplicationListener ($name, callable $callback=null)
	Add a callback to be run in every call to waitForReplication() before waiting. More...

	shutdown ($mode=self::SHUTDOWN_CHRONPROT_SYNC, callable $workCallback=null)
	Prepare all tracked load balancers for shutdown. More...

	waitForReplication (array $opts=[])
	Waits for the replica DBs to catch up to the current master position. More...

Private Member Functions
	getDBNameAndPrefix ($domain=false)

	getSectionForDomain ($domain=false)

	makeServerArray ($template, $loads, $groupLoads)
	Make a server array as expected by LoadBalancer::__construct, using a template and load array. More...

	newLoadBalancer ($template, $loads, $groupLoads, $readOnlyReason)
	Make a new load balancer object based on template and load array. More...

	reindexGroupLoads ($groupLoads)
	Take a group load array indexed by group then server, and reindex it by server then group. More...

Private Attributes
array	$conf
	Load balancer factory configuration. More...

array	$externalLoads = []
	A map of external storage cluster name to server load map. More...

array	$externalTemplateOverrides
	A set of server info keys overriding serverTemplate for external storage. More...

LoadBalancer[]	$extLBs = []

array	$groupLoadsByDB = []
	A 3-d map giving server load ratios by DB name. More...

array	$groupLoadsBySection = []
	A 3-d map giving server load ratios for each section and group. More...

array	$hostsByName = []
	A map of hostname to IP address. More...

string	$lastDomain

string	$lastSection

string	$loadMonitorClass = 'LoadMonitor'

LoadBalancer[]	$mainLBs = []

array	$masterTemplateOverrides
	An override array for all master servers. More...

array bool	$readOnlyBySection = []
	A map of section name to read-only message. More...

array	$sectionLoads
	A 2-d map. More...

array	$sectionsByDB
	A map of database names to section names. More...

array[]	$serverTemplate
	Server info associative array. More...

array	$templateOverridesByCluster
	A 2-d map overriding the server info by external storage cluster. More...

array	$templateOverridesBySection
	A 2-d map overriding the server info by section. More...

array	$templateOverridesByServer
	A 2-d map overriding serverTemplate and externalTemplateOverrides on a server-by-server basis. More...

Additional Inherited Members
Public Attributes inherited from ILBFactory
const	SHUTDOWN_CHRONPROT_ASYNC = 1

const	SHUTDOWN_CHRONPROT_SYNC = 2

const	SHUTDOWN_NO_CHRONPROT = 0

Protected Member Functions inherited from LBFactory
	baseLoadBalancerParams ()
	Base parameters to LoadBalancer::__construct() More...

	forEachLBCallMethod ($methodName, array $args=[])
	Call a method of each tracked load balancer. More...

	getChronologyProtector ()

	getScopedPHPBehaviorForCommit ()
	Make PHP ignore user aborts/disconnects until the returned value leaves scope. More...

	initLoadBalancer (ILoadBalancer $lb)

	shutdownChronologyProtector (ChronologyProtector $cp, $workCallback, $mode)
	Get and record all of the staged DB positions into persistent memory storage. More...

Protected Attributes inherited from LBFactory
string	$agent
	Agent name for query profiling. More...

ChronologyProtector	$chronProt

bool	$cliMode
	Whether this PHP instance is for a CLI script. More...

LoggerInterface	$connLogger

callable	$errorLogger
	Error logger. More...

string	$hostname
	Local hostname of the app server. More...

DatabaseDomain	$localDomain
	Local domain. More...

BagOStuff	$memCache

LoggerInterface	$perfLogger

object string	$profiler
	Class name or object With profileIn/profileOut methods. More...

LoggerInterface	$queryLogger

string bool	$readOnlyReason = false
	Reason all LBs are read-only or false if not. More...

callable[]	$replicationWaitCallbacks = []

LoggerInterface	$replLogger

array	$requestInfo
	Web request information about the client. More...

BagOStuff	$srvCache

mixed	$ticket

TransactionProfiler	$trxProfiler

string bool	$trxRoundId = false
	String if a requested DBO_TRX transaction round is active. More...

WANObjectCache	$wanCache

Detailed Description

A multi-database, multi-master factory for Wikimedia and similar installations.

Ignores the old configuration globals.

Definition at line 30 of file LBFactoryMulti.php.

Constructor & Destructor Documentation

LBFactoryMulti::__construct ( array $conf )

See also: LBFactory::__construct()

Template override precedence (highest => lowest):

templateOverridesByServer
masterTemplateOverrides
templateOverridesBySection/templateOverridesByCluster
externalTemplateOverrides
serverTemplate Overrides only work on top level keys (so nested values will not be merged).

Server configuration maps should be of the format Database::factory() requires. Additionally, a 'max lag' key should also be set on server maps, indicating how stale the data can be before the load balancer tries to avoid using it. The map can have 'is static' set to disable blocking replication sync checks (intended for archive servers with unchanging data).

Parameters

array

$conf

Parameters of LBFactory::__construct() as well as:

sectionsByDB Map of database names to section names.
sectionLoads 2-d map. For each section, gives a map of server names to load ratios. For example: [ 'section1' => [ 'db1' => 100, 'db2' => 100 ] ]
serverTemplate Server configuration map intended for Database::factory(). Note that "host", "hostName" and "load" entries will be overridden by "sectionLoads" and "hostsByName".
groupLoadsBySection 3-d map giving server load ratios for each section/group. For example: [ 'section1' => [ 'group1' => [ 'db1' => 100, 'db2' => 100 ] ] ]
groupLoadsByDB 3-d map giving server load ratios by DB name.
hostsByName Map of hostname to IP address.
externalLoads Map of external storage cluster name to server load map.
externalTemplateOverrides Set of server configuration maps overriding "serverTemplate" for external storage.
templateOverridesByServer 2-d map overriding "serverTemplate" and "externalTemplateOverrides" on a server-by-server basis. Applies to both core and external storage.
templateOverridesBySection 2-d map overriding the server configuration maps by section.
templateOverridesByCluster 2-d map overriding the server configuration maps by external storage cluster.
masterTemplateOverrides Server configuration map overrides for all master servers.
loadMonitorClass Name of the LoadMonitor class to always use.
readOnlyBySection A map of section name to read-only message. Missing or false for read/write.

Implements ILBFactory.

Definition at line 162 of file LBFactoryMulti.php.

References $conf, and as.

Member Function Documentation

LBFactoryMulti::forEachLB	(		$callback,
		array	$params = `[]`
	)

Execute a function for each tracked load balancer The callback is called with the load balancer as the first parameter, and $params passed as the subsequent parameters.

Parameters

callable	$callback
array	$params

Implements ILBFactory.

Definition at line 394 of file LBFactoryMulti.php.

References $params, and as.

LBFactoryMulti::getDBNameAndPrefix ( $domain = false )

private

Parameters

DatabaseDomain | string | bool $domain Domain ID, or false for the current domain

Returns: array [database name, table prefix]

Definition at line 379 of file LBFactoryMulti.php.

References false, and DatabaseDomain\newFromId().

Referenced by getSectionForDomain(), and newMainLB().

LBFactoryMulti::getExternalLB ( $cluster )

Get a cached (tracked) load balancer for external storage.

Parameters

string $cluster External storage cluster name

Returns: ILoadBalancer

Implements ILBFactory.

Definition at line 278 of file LBFactoryMulti.php.

References LBFactory\getChronologyProtector(), and newExternalLB().

LBFactoryMulti::getMainLB ( $domain = false )

Parameters

DatabaseDomain | string | bool $domain Domain ID, or false for the current domain

Returns: LoadBalancer

Implements ILBFactory.

Definition at line 247 of file LBFactoryMulti.php.

References $section, LBFactory\getChronologyProtector(), getSectionForDomain(), and newMainLB().

LBFactoryMulti::getSectionForDomain ( $domain = false )

private

Parameters

bool | string $domain

Returns: string

Definition at line 190 of file LBFactoryMulti.php.

References $lastSection, $section, getDBNameAndPrefix(), and list.

Referenced by getMainLB(), and newMainLB().

LBFactoryMulti::makeServerArray	(	$template,
		$loads,
		$groupLoads
	)

private

Make a server array as expected by LoadBalancer::__construct, using a template and load array.

Parameters

array	$template
array	$loads
array	$groupLoads

Returns: array

Definition at line 318 of file LBFactoryMulti.php.

References $template, as, DBO_DEFAULT, and reindexGroupLoads().

Referenced by newLoadBalancer().

LBFactoryMulti::newExternalLB ( $cluster )

Create a new load balancer for external storage.

The resulting object will be untracked, not chronology-protected, and the caller is responsible for cleaning it up.

This method is for only advanced usage and callers should almost always use getExternalLB() instead. This method can be useful when a table is used as a key/value store. In that cases, one might want to query it in autocommit mode (DBO_TRX off) but still use DBO_TRX transaction rounds on other tables.

Parameters

string $cluster External storage cluster name

Returns: ILoadBalancer

Implements ILBFactory.

Definition at line 258 of file LBFactoryMulti.php.

References $serverTemplate, $template, and newLoadBalancer().

Referenced by getExternalLB().

LBFactoryMulti::newLoadBalancer	(	$template,
		$loads,
		$groupLoads,
		$readOnlyReason
	)

private

Make a new load balancer object based on template and load array.

Parameters

array	$template
array	$loads
array	$groupLoads
string \| bool	$readOnlyReason

Returns: LoadBalancer

Definition at line 296 of file LBFactoryMulti.php.

References LBFactory\$readOnlyReason, $template, LBFactory\baseLoadBalancerParams(), LBFactory\initLoadBalancer(), and makeServerArray().

Referenced by newExternalLB(), and newMainLB().

LBFactoryMulti::newMainLB ( $domain = false )

Parameters

bool | string $domain

Returns: LoadBalancer

Implements ILBFactory.

Definition at line 210 of file LBFactoryMulti.php.

References LBFactory\$readOnlyReason, $section, $serverTemplate, $template, getDBNameAndPrefix(), getSectionForDomain(), list, and newLoadBalancer().

Referenced by getMainLB().

LBFactoryMulti::reindexGroupLoads ( $groupLoads )

private

Take a group load array indexed by group then server, and reindex it by server then group.

Parameters

array $groupLoads

Returns: array

Definition at line 364 of file LBFactoryMulti.php.

References as.

Referenced by makeServerArray().

Member Data Documentation

array LBFactoryMulti::$conf

private

Load balancer factory configuration.

Definition at line 89 of file LBFactoryMulti.php.

Referenced by __construct().

array LBFactoryMulti::$externalLoads = []

private

A map of external storage cluster name to server load map.

Definition at line 58 of file LBFactoryMulti.php.

array LBFactoryMulti::$externalTemplateOverrides

private

A set of server info keys overriding serverTemplate for external storage.

Definition at line 64 of file LBFactoryMulti.php.

LoadBalancer [] LBFactoryMulti::$extLBs = []

private

Definition at line 95 of file LBFactoryMulti.php.

array LBFactoryMulti::$groupLoadsByDB = []

private

A 3-d map giving server load ratios by DB name.

Definition at line 52 of file LBFactoryMulti.php.

array LBFactoryMulti::$groupLoadsBySection = []

private

A 3-d map giving server load ratios for each section and group.

Definition at line 49 of file LBFactoryMulti.php.

array LBFactoryMulti::$hostsByName = []

private

A map of hostname to IP address.

Definition at line 55 of file LBFactoryMulti.php.

string LBFactoryMulti::$lastDomain

private

Definition at line 101 of file LBFactoryMulti.php.

string LBFactoryMulti::$lastSection

private

Definition at line 104 of file LBFactoryMulti.php.

Referenced by getSectionForDomain().

string LBFactoryMulti::$loadMonitorClass = 'LoadMonitor'

private

Definition at line 98 of file LBFactoryMulti.php.

LoadBalancer [] LBFactoryMulti::$mainLBs = []

private

Definition at line 92 of file LBFactoryMulti.php.

array LBFactoryMulti::$masterTemplateOverrides

private

An override array for all master servers.

Definition at line 80 of file LBFactoryMulti.php.

array bool LBFactoryMulti::$readOnlyBySection = []

private

A map of section name to read-only message.

Missing or false for read/write

Definition at line 86 of file LBFactoryMulti.php.

array LBFactoryMulti::$sectionLoads

private

A 2-d map.

For each section, gives a map of server names to load ratios

Definition at line 38 of file LBFactoryMulti.php.

array LBFactoryMulti::$sectionsByDB

private

A map of database names to section names.

Definition at line 32 of file LBFactoryMulti.php.

array [] LBFactoryMulti::$serverTemplate

private

Server info associative array.

Note: The host, hostName and load entries will be overridden

Definition at line 44 of file LBFactoryMulti.php.

Referenced by newExternalLB(), and newMainLB().

array LBFactoryMulti::$templateOverridesByCluster

private

A 2-d map overriding the server info by external storage cluster.

Definition at line 77 of file LBFactoryMulti.php.

array LBFactoryMulti::$templateOverridesBySection

private

A 2-d map overriding the server info by section.

Definition at line 74 of file LBFactoryMulti.php.

array LBFactoryMulti::$templateOverridesByServer

private

A 2-d map overriding serverTemplate and externalTemplateOverrides on a server-by-server basis.

Applies to both core and external storage

Definition at line 71 of file LBFactoryMulti.php.

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

includes/libs/rdbms/lbfactory/LBFactoryMulti.php

Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation