Manage locks using memcached servers. More...

Inheritance diagram for MemcLockManager:

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Collaboration diagram for MemcLockManager:

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Public Member Functions
	__construct (array $config)
	Construct a new instance from configuration.

	__destruct ()
	Make sure remaining locks get cleared for sanity.

Public Member Functions inherited from LockManager
	lock (array $paths, $type=self::LOCK_EX, $timeout=0)
	Lock the resources at the given abstract paths.

	lockByType (array $pathsByType, $timeout=0)
	Lock the resources at the given abstract paths.

	unlock (array $paths, $type=self::LOCK_EX)
	Unlock the resources at the given abstract paths.

	unlockByType (array $pathsByType)
	Unlock the resources at the given abstract paths.

Protected Member Functions
	acquireMutexes (MemcachedBagOStuff $memc, array $keys)

	doFreeLocksOnServer ( $lockSrv, array $paths, $type)

	doGetLocksOnServer ( $lockSrv, array $paths, $type)

	freeLocksOnServer ( $lockSrv, array $pathsByType)
	Get a connection to a lock server and release locks on $paths.

	getCache ( $lockSrv)
	Get the MemcachedBagOStuff object for a $lockSrv.

	getLocksOnServer ( $lockSrv, array $pathsByType)
	Get a connection to a lock server and acquire locks.

	isServerUp ( $lockSrv)

	recordKeyForPath ( $path)

	releaseAllLocks ()

	releaseMutexes (MemcachedBagOStuff $memc, array $keys)

Protected Member Functions inherited from QuorumLockManager
	doLock (array $paths, $type)
	Lock resources with the given keys and lock type.

	doLockByType (array $pathsByType)

	doLockingRequestBucket ( $bucket, array $pathsByType)
	Attempt to acquire locks with the peers for a bucket.

	doUnlock (array $paths, $type)
	Unlock resources with the given keys and lock type.

	doUnlockByType (array $pathsByType)

	doUnlockingRequestBucket ( $bucket, array $pathsByType)
	Attempt to release locks with the peers for a bucket.

	getBucketFromPath ( $path)
	Get the bucket for resource path.

Protected Member Functions inherited from LockManager
	normalizePathsByType (array $pathsByType)
	Normalize the $paths array by converting LOCK_UW locks into the appropriate type and removing any duplicated paths for each lock type.

	sha1Base16Absolute ( $path)
	Get the base 16 SHA-1 of a string, padded to 31 digits.

	sha1Base36Absolute ( $path)
	Get the base 36 SHA-1 of a string, padded to 31 digits.

Static Protected Member Functions
static	newLockArray ()

static	sanitizeLockArray ( $a)

Protected Attributes
array	$bagOStuffs = []
	Map server names to MemcachedBagOStuff objects.

array	$lockTypeMap
	Mapping of lock types to the type actually used.

array	$serversUp = []
	(server name => bool)

string	$session = ''
	Random UUID.

Protected Attributes inherited from QuorumLockManager
array	$degradedBuckets = []
	Map of degraded buckets.

array	$srvsByBucket = []
	Map of bucket indexes to peer server lists.

Protected Attributes inherited from LockManager
	$domain

array	$locksHeld = []
	Map of (resource path => lock type => count)

	$lockTTL

array	$lockTypeMap
	Mapping of lock types to the type actually used.

Additional Inherited Members
Public Attributes inherited from LockManager
const	LOCK_EX = 3

const	LOCK_SH = 1
	Lock types; stronger locks have higher values.

const	LOCK_UW = 2

Detailed Description

Manage locks using memcached servers.

Version of LockManager based on using memcached servers. This is meant for multi-wiki systems that may share files. All locks are non-blocking, which avoids deadlocks.

All lock requests for a resource, identified by a hash string, will map to one bucket. Each bucket maps to one or several peer servers, each running memcached. A majority of peers must agree for a lock to be acquired.

Since: 1.20

Definition at line 38 of file MemcLockManager.php.

Constructor & Destructor Documentation

◆ __construct()

MemcLockManager::__construct ( array $config )

Construct a new instance from configuration.

Parameters

array

$config

Parameters include:

lockServers : Associative array of server names to "<IP>:<port>" strings.
srvsByBucket : Array of 1-16 consecutive integer keys, starting from 0, each having an odd-numbered list of server names (peers) as values.
memcConfig : Configuration array for ObjectCache::newFromParams. [optional] If set, this must use one of the memcached classes.

Exceptions

Exception

Reimplemented from LockManager.

Definition at line 66 of file MemcLockManager.php.

References $cache, $name, $params, as, ObjectCache\newFromParams(), and wfRandomString().

◆ __destruct()

MemcLockManager::__destruct ( )

Make sure remaining locks get cleared for sanity.

Definition at line 376 of file MemcLockManager.php.

References $path, as, and QuorumLockManager\doUnlock().

Member Function Documentation

◆ acquireMutexes()

MemcLockManager::acquireMutexes	(	MemcachedBagOStuff	$memc,
		array	$keys
	)

protected

Parameters

MemcachedBagOStuff	$memc
array	$keys	List of keys to acquire

Returns: bool

Definition at line 330 of file MemcLockManager.php.

References $keys, MemcachedBagOStuff\add(), as, and releaseMutexes().

Referenced by doFreeLocksOnServer(), and doGetLocksOnServer().

◆ doFreeLocksOnServer()

MemcLockManager::doFreeLocksOnServer	(		$lockSrv,
		array	$paths,
			$type
	)

protected

See also: QuorumLockManager::freeLocksOnServer()

Parameters

string	$lockSrv
array	$paths
string	$type

Returns: Status

Definition at line 207 of file MemcLockManager.php.

References $keys, LockManager\$locksHeld, $path, $status, $type, acquireMutexes(), as, getCache(), recordKeyForPath(), releaseMutexes(), sanitizeLockArray(), and wfDebug().

Referenced by freeLocksOnServer(), and getLocksOnServer().

◆ doGetLocksOnServer()

MemcLockManager::doGetLocksOnServer	(		$lockSrv,
		array	$paths,
			$type
	)

protected

See also: QuorumLockManager::getLocksOnServer()

Parameters

string	$lockSrv
array	$paths
string	$type

Returns: Status

Definition at line 131 of file MemcLockManager.php.

References $keys, LockManager\$locksHeld, LockManager\$lockTTL, $path, $session, $status, $type, acquireMutexes(), as, getCache(), newLockArray(), recordKeyForPath(), releaseMutexes(), sanitizeLockArray(), and wfDebug().

Referenced by getLocksOnServer().

◆ freeLocksOnServer()

MemcLockManager::freeLocksOnServer	(		$lockSrv,
		array	$pathsByType
	)

protected

Get a connection to a lock server and release locks on $paths.

Subclasses must effectively implement this or releaseAllLocks().

Parameters

string	$lockSrv
array	$pathsByType	Map of LockManager::LOCK_* constants to lists of paths

Returns: Status

Reimplemented from QuorumLockManager.

Definition at line 114 of file MemcLockManager.php.

References $status, $type, as, and doFreeLocksOnServer().

◆ getCache()

MemcLockManager::getCache ( $lockSrv )

protected

Get the MemcachedBagOStuff object for a $lockSrv.

Parameters

string $lockSrv Server name

Returns: MemcachedBagOStuff|null

Definition at line 278 of file MemcLockManager.php.

Referenced by doFreeLocksOnServer(), doGetLocksOnServer(), and isServerUp().

◆ getLocksOnServer()

MemcLockManager::getLocksOnServer	(		$lockSrv,
		array	$pathsByType
	)

protected

Get a connection to a lock server and acquire locks.

Parameters

string	$lockSrv
array	$pathsByType	Map of LockManager::LOCK_* constants to lists of paths

Returns: Status

Reimplemented from QuorumLockManager.

Definition at line 92 of file MemcLockManager.php.

References $status, $type, as, doFreeLocksOnServer(), and doGetLocksOnServer().

◆ isServerUp()

MemcLockManager::isServerUp ( $lockSrv )

protected

See also: QuorumLockManager::isServerUp()

Parameters

string $lockSrv

Returns: bool

Reimplemented from QuorumLockManager.

Definition at line 268 of file MemcLockManager.php.

References getCache().

◆ newLockArray()

static MemcLockManager::newLockArray ( )

staticprotected

Returns: array An empty lock structure for a key

Definition at line 307 of file MemcLockManager.php.

Referenced by doGetLocksOnServer(), and sanitizeLockArray().

◆ recordKeyForPath()

MemcLockManager::recordKeyForPath ( $path )

protected

Parameters

string $path

Returns: string

Definition at line 300 of file MemcLockManager.php.

References $path, and LockManager\sha1Base36Absolute().

Referenced by doFreeLocksOnServer(), and doGetLocksOnServer().

◆ releaseAllLocks()

MemcLockManager::releaseAllLocks ( )

protected

See also: QuorumLockManager::releaseAllLocks()

Returns: Status

Reimplemented from QuorumLockManager.

Definition at line 259 of file MemcLockManager.php.

◆ releaseMutexes()

MemcLockManager::releaseMutexes	(	MemcachedBagOStuff	$memc,
		array	$keys
	)

protected

Parameters

MemcachedBagOStuff	$memc
array	$keys	List of acquired keys

Definition at line 367 of file MemcLockManager.php.

References $keys, as, and MemcachedBagOStuff\delete().

Referenced by acquireMutexes(), doFreeLocksOnServer(), and doGetLocksOnServer().

◆ sanitizeLockArray()

static MemcLockManager::sanitizeLockArray ( $a )

staticprotected

Parameters

array $a

Returns: array An empty lock structure for a key

Definition at line 315 of file MemcLockManager.php.

References newLockArray().

Referenced by doFreeLocksOnServer(), and doGetLocksOnServer().

Member Data Documentation

◆ $bagOStuffs

array MemcLockManager::$bagOStuffs = []

protected

Map server names to MemcachedBagOStuff objects.

Definition at line 47 of file MemcLockManager.php.

◆ $lockTypeMap

array MemcLockManager::$lockTypeMap

protected

Initial value:

= [
        self::LOCK_SH => self::LOCK_SH,
        self::LOCK_UW => self::LOCK_SH,
        self::LOCK_EX => self::LOCK_EX
    ]

Mapping of lock types to the type actually used.

Definition at line 40 of file MemcLockManager.php.

◆ $serversUp

array MemcLockManager::$serversUp = []

protected

(server name => bool)

Definition at line 50 of file MemcLockManager.php.

◆ $session

string MemcLockManager::$session = ''

protected

Random UUID.

Definition at line 53 of file MemcLockManager.php.

Referenced by doGetLocksOnServer().

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

includes/filebackend/lockmanager/MemcLockManager.php

Public Member Functions

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ __construct()

◆ __destruct()

Member Function Documentation

◆ acquireMutexes()

◆ doFreeLocksOnServer()

◆ doGetLocksOnServer()

◆ freeLocksOnServer()

◆ getCache()

◆ getLocksOnServer()

◆ isServerUp()

◆ newLockArray()

◆ recordKeyForPath()

◆ releaseAllLocks()

◆ releaseMutexes()

◆ sanitizeLockArray()

Member Data Documentation

◆ $bagOStuffs

◆ $lockTypeMap

◆ $serversUp

◆ $session