MediaWiki master
Wikimedia\Rdbms\LBFactory Class Reference

Inherits Wikimedia\Rdbms\ILBFactory.

Inherited by Wikimedia\Rdbms\LBFactoryMulti, Wikimedia\Rdbms\LBFactorySimple, and Wikimedia\Rdbms\LBFactorySingle.

Collaboration diagram for Wikimedia\Rdbms\LBFactory:

Public Member Functions

 __construct (array $conf)
 Sub-classes may extend the required keys in $conf with additional parameters.
 
 autoReconfigure ()
 Reload config using the callback passed defined $config['configCallback'].
 
 beginPrimaryChanges ( $fname=__METHOD__)
 Wrap subsequent queries for all transaction round aware primary connections in a transaction.
 
 closeAll ( $fname=__METHOD__)
 Close all connections on instantiated tracked load balancer instances.
 
 commitAndWaitForReplication ( $fname, $ticket, array $opts=[])
 Commit primary DB transactions and wait for replication (if $ticket indicates it is safe).
 
 commitPrimaryChanges ( $fname=__METHOD__, int $maxWriteDuration=0)
 Commit all primary connection transactions and flush all replica connection transactions.
 
 destroy ()
 Close all connections and make further attempts to open connections result in DBAccessError.
 
 disableChronologyProtection ()
 Disable the ChronologyProtector on all instantiated tracked load balancer instances.
 
 flushPrimarySessions ( $fname=__METHOD__)
 Release important session-level state (named lock, table locks) as post-rollback cleanup.
 
 flushReplicaSnapshots ( $fname=__METHOD__)
 Commit all replica database server transactions, clearing any point-in-time view snapshots.
 
 getAllLBs ()
 Get all tracked load balancer instances (generator)
 
 getEmptyTransactionTicket ( $fname)
 Get a token asserting that no write transactions are active on tracked connections.
 
 getLoadBalancer ( $domain=false)
 Get the tracked load balancer instance for a given domain.
 
 getLocalDomainID ()
 Get the local (and default) database domain ID of connection handles.
 
 getPrimaryDatabase ( $domain=false)
 Get connection to the primary database.
 
 getReplicaDatabase ( $domain=false, $group=null)
 Get connection to a replica database.
 
 getTransactionProfiler ()
 Get the TransactionProfiler used by this instance.
 
 hasOrMadeRecentPrimaryChanges ( $age=null)
 Determine if any primary connection has pending/written changes from this request.
 
 hasPrimaryChanges ()
 Determine if any primary connection has pending changes.
 
 hasStreamingReplicaServers ()
 Whether it has streaming replica servers.
 
 hasTransactionRound ()
 Check if an explicit transaction round is active.
 
 isReadyForRoundOperations ()
 Check if transaction rounds can be started, committed, or rolled back right now.
 
 laggedReplicaUsed ()
 Determine if any lagged replica database server connection was used.
 
 reconfigure (array $conf)
 Reconfigure using the given config array.
 
 redefineLocalDomain ( $domain)
 Close all connections and redefine the local database domain.
 
 rollbackPrimaryChanges ( $fname=__METHOD__)
 Rollback all primary connection transactions and flush all replica connection transactions.
 
 setAgentName ( $agent)
 
 setDefaultReplicationWaitTimeout ( $seconds)
 Set the default timeout for replication wait checks.
 
 setDomainAliases (array $aliases)
 Convert certain database domains to alternative ones.
 
 setIndexAliases (array $aliases)
 Convert certain index names to alternative names before querying the DB.
 
 setLocalDomainPrefix ( $prefix)
 Set a new table prefix for the existing local domain ID for testing.
 
 setTableAliases (array $aliases)
 Make certain table names use their own database, schema, and table prefix when passed into SQL queries pre-escaped and without a qualified database name.
 
 setWaitForReplicationListener ( $name, ?callable $callback=null)
 Add a callback to be run in every call to waitForReplication() prior to any waiting.
 
 shutdown ( $flags=self::SHUTDOWN_NORMAL, ?callable $workCallback=null, &$cpIndex=null, &$cpClientId=null)
 Prepare all instantiated tracked load balancer instances for shutdown.
 
 waitForReplication (array $opts=[])
 Waits for the replica database server to catch up to the current primary position.
 
- Public Member Functions inherited from Wikimedia\Rdbms\ILBFactory
 getAllExternalLBs ()
 Get the tracked load balancer instances for all external clusters.
 
 getAllMainLBs ()
 Get the tracked load balancer instances for all main clusters.
 
 getExternalLB ( $cluster)
 Get the tracked load balancer instance for an external cluster.
 
 getMainLB ( $domain=false)
 Get the tracked load balancer instance for the main cluster that handles the given domain.
 
 newExternalLB ( $cluster)
 Create a new load balancer instance for an external cluster.
 
 newMainLB ( $domain=false)
 Create a new load balancer instance for the main cluster that handles the given domain.
 

Protected Member Functions

 baseLoadBalancerParams ()
 Get parameters to ILoadBalancer::__construct()
 
 configure (array $conf)
 
 getLBsForOwner ()
 Get all tracked load balancers with the internal "for owner" interface.
 
 initLoadBalancer (ILoadBalancerForOwner $lb)
 

Protected Attributes

ChronologyProtector $chronologyProtector
 
DatabaseDomain[] string[] $domainAliases = []
 Map of (domain alias => DB domain)
 
DatabaseDomain $localDomain
 Local domain.
 
string false $readOnlyReason = false
 Reason all LBs are read-only or false if not.
 
BagOStuff $srvCache
 
array string[] $virtualDomains = []
 List of registered virtual domains.
 
array array[] $virtualDomainsMapping = []
 Map of virtual domain to array of cluster and domain.
 
WANObjectCache $wanCache
 

Additional Inherited Members

- Public Attributes inherited from Wikimedia\Rdbms\ILBFactory
const SHUTDOWN_NO_CHRONPROT = 1
 Do not save "session consistency" DB replication positions.
 
const SHUTDOWN_NORMAL = 0
 Idiom for "no special shutdown flags".
 

Detailed Description

See also
ILBFactory

Definition at line 40 of file LBFactory.php.

Constructor & Destructor Documentation

◆ __construct()

Wikimedia\Rdbms\LBFactory::__construct ( array $conf)

Sub-classes may extend the required keys in $conf with additional parameters.

Parameters
array$confArray with keys:
  • localDomain: A DatabaseDomain or database domain ID string
  • virtualDomains: List of virtual database domain ID strings [optional]. These can be passed to {
See also
ILBFactory::getPrimaryDatabase()} and {
ILBFactory::getReplicaDatabase()}, with the actual cluster and database domain being automatically resolved via "virtualDomainsMapping". Virtual database domains not defined there will resolve to the local database domain.
  • virtualDomainsMapping: Map of (virtual database domain ID => config map) [optional]. Each config map has a "db" key and an optional "cluster" key. The "db" key specifies the actual database domain configured for use, with false indicating that the local database domain is configured for use. The "cluster" key, if provided, specifies the name of the external cluster configured for use, otherwise, the main cluster for the actual database domain will be used.
  • chronologyProtector: ChronologyProtector instance [optional]
  • readOnlyReason: Reason the primary server is read-only (false if not)
  • srvCache: BagOStuff instance for server cache [optional]
  • cpStash: BagOStuff instance for ChronologyProtector store [optional]. See ChronologyProtector requirements.
  • wanCache: WANObjectCache instance [optional]
  • cliMode: Whether the execution context is a CLI script [optional]
  • profiler: Callback that takes a profile section name and returns a ScopedCallback that ends the profile section in its destructor [optional]
  • trxProfiler: TransactionProfiler instance [optional]
  • logger: PSR-3 logger instance [optional]
  • errorLogger: Callback that takes an Exception and logs it [optional]
  • deprecationLogger: Callback to log a deprecation warning [optional]
  • secret: Secret string to use for HMAC hashing [optional]
  • criticalSectionProvider: CriticalSectionProvider instance [optional]

Implements Wikimedia\Rdbms\ILBFactory.

Reimplemented in Wikimedia\Rdbms\LBFactoryMulti, Wikimedia\Rdbms\LBFactorySimple, and Wikimedia\Rdbms\LBFactorySingle.

Definition at line 114 of file LBFactory.php.

References Wikimedia\Rdbms\LBFactory\configure().

Member Function Documentation

◆ autoReconfigure()

Wikimedia\Rdbms\LBFactory::autoReconfigure ( )

Reload config using the callback passed defined $config['configCallback'].

If the config returned by the callback is different from the existing config, this calls reconfigure() on all load balancers, which causes them to invalidate any existing connections and re-connect using the new configuration.

Long-running processes should call this from time to time (but not too often, because it is somewhat expensive), preferably after each batch. Maintenance scripts can do that by calling $this->waitForReplication(), which calls this method.

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 186 of file LBFactory.php.

◆ baseLoadBalancerParams()

Wikimedia\Rdbms\LBFactory::baseLoadBalancerParams ( )
finalprotected

Get parameters to ILoadBalancer::__construct()

Returns
array

Definition at line 620 of file LBFactory.php.

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

◆ beginPrimaryChanges()

Wikimedia\Rdbms\LBFactory::beginPrimaryChanges ( $fname = __METHOD__)
final

Wrap subsequent queries for all transaction round aware primary connections in a transaction.

Each of these transactions will be owned by this ILBFactory instance such that direct calls to IDatabase::commit() or IDatabase::rollback() will be disabled. These transactions get resolved by a single call to either commitPrimaryChanges() or rollbackPrimaryChanges(), after which, the transaction wrapping and ownership behavior revert back to the default. When there are multiple connections involved, these methods perform best-effort distributed transactions. When using distributed transactions, the RDBMS should be configured to used pessimistic concurrency control such that the commit step of each transaction is unlikely to fail.

Transactions on replication connections are flushed so that future reads will not keep using the same point-in-time view snapshots (e.g. from MySQL REPEATABLE-READ). However, this does not wait for replication to catch up, so subsequent reads from replicas might not reflect recently committed changes.

This only applies to the tracked load balancer instances.

This allows for custom transaction rounds from any outer transaction scope.

Parameters
string$fname
Exceptions
DBTransactionError
Since
1.37

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 281 of file LBFactory.php.

◆ closeAll()

Wikimedia\Rdbms\LBFactory::closeAll ( $fname = __METHOD__)

Close all connections on instantiated tracked load balancer instances.

Parameters
string$fnameCaller name (e.g. METHOD)

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 700 of file LBFactory.php.

◆ commitAndWaitForReplication()

Wikimedia\Rdbms\LBFactory::commitAndWaitForReplication ( $fname,
$ticket,
array $opts = [] )
final

Commit primary DB transactions and wait for replication (if $ticket indicates it is safe).

This is mostly used in jobs or deferred updates dealing with batching.

The ticket is used to check that the caller owns the transaction round or can act on behalf of the caller that owns the transaction round.

See also
ILBFactory::commitPrimaryChanges()
ILBFactory::waitForReplication()
Since
1.28
Parameters
string$fnameCaller name (e.g. METHOD)
mixed$ticketResult of getEmptyTransactionTicket()
array$optsOptions to waitForReplication()
Returns
bool True if the wait was successful, false on timeout

Implements Wikimedia\Rdbms\IConnectionProvider.

Definition at line 581 of file LBFactory.php.

Referenced by CategoryMembershipChangeJob\notifyUpdatesForRevision().

◆ commitPrimaryChanges()

Wikimedia\Rdbms\LBFactory::commitPrimaryChanges ( $fname = __METHOD__,
int $maxWriteDuration = 0 )
final

Commit all primary connection transactions and flush all replica connection transactions.

Transactions on replication connections are flushed so that future reads will not keep using the same point-in-time view snapshots (e.g. from MySQL REPEATABLE-READ). However, this does not wait for replication to catch up, so subsequent reads from replicas might not reflect the committed changes.

This only applies to the instantiated tracked load balancer instances.

Parameters
string$fnameCaller name
int$maxWriteDurationabort if more than this much time was spent in write queries
Exceptions
DBTransactionError
Since
1.37

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 305 of file LBFactory.php.

◆ configure()

Wikimedia\Rdbms\LBFactory::configure ( array $conf)
protected
Parameters
array$conf
Returns
void

Definition at line 126 of file LBFactory.php.

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

◆ destroy()

Wikimedia\Rdbms\LBFactory::destroy ( )

Close all connections and make further attempts to open connections result in DBAccessError.

This only applies to the tracked load balancer instances.

See also
ILoadBalancer::disable()

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 164 of file LBFactory.php.

◆ disableChronologyProtection()

Wikimedia\Rdbms\LBFactory::disableChronologyProtection ( )

Disable the ChronologyProtector on all instantiated tracked load balancer instances.

This can be called at the start of special API entry points.

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 611 of file LBFactory.php.

◆ flushPrimarySessions()

Wikimedia\Rdbms\LBFactory::flushPrimarySessions ( $fname = __METHOD__)
final

Release important session-level state (named lock, table locks) as post-rollback cleanup.

This only applies to the instantiated tracked load balancer instances.

This should only be called by application entry point functions, since there must be no chance that a future caller will still be expecting some of the lost session state.

Parameters
string$fnameCaller name
Since
1.38

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 369 of file LBFactory.php.

◆ flushReplicaSnapshots()

Wikimedia\Rdbms\LBFactory::flushReplicaSnapshots ( $fname = __METHOD__)

Commit all replica database server transactions, clearing any point-in-time view snapshots.

This only applies to the instantiated tracked load balancer instances.

This is useful for getting rid of stale data from an implicit transaction round

Parameters
string$fnameCaller name
Deprecated
Since 1.43

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 269 of file LBFactory.php.

◆ getAllLBs()

Wikimedia\Rdbms\LBFactory::getAllLBs ( )

Get all tracked load balancer instances (generator)

Returns
Generator|ILoadBalancer[]
Since
1.39

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 256 of file LBFactory.php.

◆ getEmptyTransactionTicket()

Wikimedia\Rdbms\LBFactory::getEmptyTransactionTicket ( $fname)

Get a token asserting that no write transactions are active on tracked connections.

This is mostly used in jobs or deferred updates dealing with batching.

Since
1.28
Parameters
string$fnameCaller name (e.g. METHOD)
Returns
mixed A value to pass to commitAndWaitForReplication()

Implements Wikimedia\Rdbms\IConnectionProvider.

Definition at line 521 of file LBFactory.php.

◆ getLBsForOwner()

Wikimedia\Rdbms\LBFactory::getLBsForOwner ( )
abstractprotected

Get all tracked load balancers with the internal "for owner" interface.

Returns
Generator|ILoadBalancerForOwner[]

Reimplemented in Wikimedia\Rdbms\LBFactoryMulti, Wikimedia\Rdbms\LBFactorySimple, and Wikimedia\Rdbms\LBFactorySingle.

◆ getLoadBalancer()

Wikimedia\Rdbms\LBFactory::getLoadBalancer ( $domain = false)

Get the tracked load balancer instance for a given domain.

If no tracked instances exists, then one will be instantiated.

This method accepts virtual domains ({

See also
\MediaWiki\MainConfigSchema::VirtualDomainsMapping}).
Since
1.43
Parameters
string | false$domainDomain ID, or false for the current domain
Returns
ILoadBalancer

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 547 of file LBFactory.php.

◆ getLocalDomainID()

Wikimedia\Rdbms\LBFactory::getLocalDomainID ( )

Get the local (and default) database domain ID of connection handles.

See also
DatabaseDomain
Returns
string Database domain ID; this specifies DB name, schema, and table prefix
Since
1.32

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 225 of file LBFactory.php.

◆ getPrimaryDatabase()

Wikimedia\Rdbms\LBFactory::getPrimaryDatabase ( $domain = false)

Get connection to the primary database.

This should be used when there the code needs to write to the database.

This method accepts virtual domains ({

See also
\MediaWiki\MainConfigSchema::VirtualDomainsMapping}).
Since
1.40
Parameters
string | false$domainDomain ID, or false for the current domain
Returns
IDatabase

Implements Wikimedia\Rdbms\IConnectionProvider.

Definition at line 534 of file LBFactory.php.

Referenced by MediaWiki\Deferred\LinksUpdate\LinksTable\injectBaseDependencies().

◆ getReplicaDatabase()

Wikimedia\Rdbms\LBFactory::getReplicaDatabase ( $domain = false,
$group = null )

Get connection to a replica database.

Note that a read can have replication lag.

This method accepts virtual domains ({

See also
\MediaWiki\MainConfigSchema::VirtualDomainsMapping}).
Since
1.40
Parameters
string | false$domainDomain ID, or false for the current domain
string | null$groupQuery group; null for the default group
Returns
IReadableDatabase

Implements Wikimedia\Rdbms\IConnectionProvider.

Definition at line 538 of file LBFactory.php.

◆ getTransactionProfiler()

Wikimedia\Rdbms\LBFactory::getTransactionProfiler ( )

Get the TransactionProfiler used by this instance.

Returns
TransactionProfiler
Since
1.35

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 674 of file LBFactory.php.

◆ hasOrMadeRecentPrimaryChanges()

Wikimedia\Rdbms\LBFactory::hasOrMadeRecentPrimaryChanges ( $age = null)

Determine if any primary connection has pending/written changes from this request.

This only applies to the instantiated tracked load balancer instances.

Parameters
float | null$ageHow many seconds ago is "recent" [defaults to LB lag wait timeout]
Returns
bool

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 452 of file LBFactory.php.

◆ hasPrimaryChanges()

Wikimedia\Rdbms\LBFactory::hasPrimaryChanges ( )

Determine if any primary connection has pending changes.

This only applies to the instantiated tracked load balancer instances.

Returns
bool
Since
1.37

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 434 of file LBFactory.php.

◆ hasStreamingReplicaServers()

Wikimedia\Rdbms\LBFactory::hasStreamingReplicaServers ( )

Whether it has streaming replica servers.

Since
1.41
Returns
bool

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 713 of file LBFactory.php.

◆ hasTransactionRound()

Wikimedia\Rdbms\LBFactory::hasTransactionRound ( )

Check if an explicit transaction round is active.

Returns
bool
Since
1.29

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 403 of file LBFactory.php.

◆ initLoadBalancer()

◆ isReadyForRoundOperations()

Wikimedia\Rdbms\LBFactory::isReadyForRoundOperations ( )

Check if transaction rounds can be started, committed, or rolled back right now.

This can be used as a recursion guard to avoid exceptions in transaction callbacks.

Returns
bool
Since
1.32

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 407 of file LBFactory.php.

◆ laggedReplicaUsed()

Wikimedia\Rdbms\LBFactory::laggedReplicaUsed ( )

Determine if any lagged replica database server connection was used.

This only applies to the instantiated tracked load balancer instances.

Returns
bool

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 443 of file LBFactory.php.

◆ reconfigure()

Wikimedia\Rdbms\LBFactory::reconfigure ( array $conf)

Reconfigure using the given config array.

Any fields omitted from $conf will be taken from the current config.

If the config changed, this calls reconfigure() on all load balancers, which causes them to close all existing connections.

Note
This invalidates the current transaction ticket.
Warning
This must only be called in top level code such as the execute() method of a maintenance script. Any database connection in use when this method is called will become defunct.
Since
1.39
Parameters
array$confA configuration array, using the same structure as the one passed to the constructor (see also $wgLBFactoryConf).

Reimplemented in Wikimedia\Rdbms\LBFactoryMulti.

Definition at line 215 of file LBFactory.php.

◆ redefineLocalDomain()

Wikimedia\Rdbms\LBFactory::redefineLocalDomain ( $domain)

Close all connections and redefine the local database domain.

This only applies to the tracked load balancer instances.

This method is only intended for use with schema creation or integration testing

Parameters
DatabaseDomain | string$domain
Since
1.33

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 690 of file LBFactory.php.

◆ rollbackPrimaryChanges()

Wikimedia\Rdbms\LBFactory::rollbackPrimaryChanges ( $fname = __METHOD__)
final

Rollback all primary connection transactions and flush all replica connection transactions.

This only applies to the instantiated tracked load balancer instances.

Parameters
string$fnameCaller name
Since
1.37

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 349 of file LBFactory.php.

◆ setAgentName()

Wikimedia\Rdbms\LBFactory::setAgentName ( $agent)
Parameters
string$agentAgent name for query profiling

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 709 of file LBFactory.php.

◆ setDefaultReplicationWaitTimeout()

Wikimedia\Rdbms\LBFactory::setDefaultReplicationWaitTimeout ( $seconds)

Set the default timeout for replication wait checks.

Parameters
int$secondsTimeout, in seconds
Returns
int The previous default timeout
Since
1.35

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 722 of file LBFactory.php.

◆ setDomainAliases()

Wikimedia\Rdbms\LBFactory::setDomainAliases ( array $aliases)

Convert certain database domains to alternative ones.

This can be used for backwards compatibility logic.

Parameters
DatabaseDomain[] | string[]$aliasesMap of (domain alias => domain)
Since
1.35

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 670 of file LBFactory.php.

◆ setIndexAliases()

Wikimedia\Rdbms\LBFactory::setIndexAliases ( array $aliases)

Convert certain index names to alternative names before querying the DB.

Note that this applies to indexes regardless of the table they belong to.

This can be employed when an index was renamed X => Y in code, but the new Y-named indexes were not yet built on all DBs. After all the Y-named ones are added by the DBA, the aliases can be removed, and then the old X-named indexes dropped.

Parameters
string[]$aliasesMap of (index alias => index name)
Since
1.31

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 666 of file LBFactory.php.

◆ setLocalDomainPrefix()

Wikimedia\Rdbms\LBFactory::setLocalDomainPrefix ( $prefix)

Set a new table prefix for the existing local domain ID for testing.

Parameters
string$prefix
Since
1.33

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 678 of file LBFactory.php.

◆ setTableAliases()

Wikimedia\Rdbms\LBFactory::setTableAliases ( array $aliases)

Make certain table names use their own database, schema, and table prefix when passed into SQL queries pre-escaped and without a qualified database name.

For example, "user" can be converted to "myschema.mydbname.user" for convenience. Appearances like user, somedb.user, somedb.someschema.user will used literally.

Calling this twice will completely clear any old table aliases. Also, note that callers are responsible for making sure the schemas and databases actually exist.

Parameters
array[]$aliasesMap of (table => (dbname, schema, prefix) map)
Since
1.31

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 662 of file LBFactory.php.

◆ setWaitForReplicationListener()

Wikimedia\Rdbms\LBFactory::setWaitForReplicationListener ( $name,
?callable $callback = null )

Add a callback to be run in every call to waitForReplication() prior to any waiting.

Callbacks must clear any transactions that they start.

Parameters
string$nameCallback name
callable | null$callbackUse null to unset a callback

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 513 of file LBFactory.php.

◆ shutdown()

Wikimedia\Rdbms\LBFactory::shutdown ( $flags = self::SHUTDOWN_NORMAL,
?callable $workCallback = null,
& $cpIndex = null,
& $cpClientId = null )

Prepare all instantiated tracked load balancer instances for shutdown.

Parameters
int$flagsBit field of ILBFactory::SHUTDOWN_* constants
callable | null$workCallbackWork to mask ChronologyProtector writes
int | null&$cpIndexPosition key write counter for ChronologyProtector [returned]
string | null&$cpClientIdClient ID hash for ChronologyProtector [returned]

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 229 of file LBFactory.php.

◆ waitForReplication()

Wikimedia\Rdbms\LBFactory::waitForReplication ( array $opts = [])

Waits for the replica database server to catch up to the current primary position.

Use this when updating very large numbers of rows, as in maintenance scripts, to avoid causing too much lag. This is a no-op if there are no replica database servers.

By default this waits on all DB clusters actually used in this request. This makes sense when lag being waiting on is caused by the code that does this check. In that case, setting "ifWritesSince" can avoid the overhead of waiting for clusters that were not changed since the last wait check.

Never call this function after a large DB write that is still in a transaction. It only makes sense to call this after the possible lag inducing changes were committed.

This only applies to the instantiated tracked load balancer instances.

Parameters
array$optsOptional fields that include:
  • timeout: Max wait time. Default: 60 seconds for CLI, 1 second for web.
  • ifWritesSince: Only wait if writes were done since this UNIX timestamp.
Returns
bool True on success, false if a timeout or error occurred while waiting

Implements Wikimedia\Rdbms\ILBFactory.

Definition at line 461 of file LBFactory.php.

Member Data Documentation

◆ $chronologyProtector

ChronologyProtector Wikimedia\Rdbms\LBFactory::$chronologyProtector
protected

Definition at line 60 of file LBFactory.php.

◆ $domainAliases

DatabaseDomain [] string [] Wikimedia\Rdbms\LBFactory::$domainAliases = []
protected

Map of (domain alias => DB domain)

Definition at line 78 of file LBFactory.php.

◆ $localDomain

DatabaseDomain Wikimedia\Rdbms\LBFactory::$localDomain
protected

Local domain.

Definition at line 66 of file LBFactory.php.

◆ $readOnlyReason

string false Wikimedia\Rdbms\LBFactory::$readOnlyReason = false
protected

Reason all LBs are read-only or false if not.

Definition at line 96 of file LBFactory.php.

◆ $srvCache

BagOStuff Wikimedia\Rdbms\LBFactory::$srvCache
protected

Definition at line 62 of file LBFactory.php.

◆ $virtualDomains

array string [] Wikimedia\Rdbms\LBFactory::$virtualDomains = []
protected

List of registered virtual domains.

Definition at line 82 of file LBFactory.php.

◆ $virtualDomainsMapping

array array [] Wikimedia\Rdbms\LBFactory::$virtualDomainsMapping = []
protected

Map of virtual domain to array of cluster and domain.

Definition at line 80 of file LBFactory.php.

◆ $wanCache

WANObjectCache Wikimedia\Rdbms\LBFactory::$wanCache
protected

Definition at line 64 of file LBFactory.php.


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