Version of PoolCounter that uses Redis. More...

Inheritance diagram for PoolCounterRedis:

Collaboration diagram for PoolCounterRedis:

[legend]

Public Member Functions
	__construct ( $conf, $type, $key)

	acquireForAnyone ()
	I want to do this task, but if anyone else does it instead, it's also fine for me. More...

	acquireForMe ()
	I want to do this task and I need to do it myself. More...

	release ()
	I have successfully finished my task. More...

Public Member Functions inherited from PoolCounter
	getKey ()

Static Public Member Functions
static	releaseAll ()
	Try to make sure that locks get released (even with exceptions and fatals) More...

Static Public Member Functions inherited from PoolCounter
static	factory ( $type, $key)
	Create a Pool counter. More...

Public Attributes
const	AWAKE_ALL = 2

const	AWAKE_ONE = 1

Public Attributes inherited from PoolCounter
const	DONE = 3

const	ERROR = -1

const	LOCK_HELD = -5

const	LOCKED = 1

const	NOT_LOCKED = -2

const	QUEUE_FULL = -3

const	RELEASED = 2

const	TIMEOUT = -4

Protected Member Functions
	getConnection ()

	getSlotListKey ()

	getSlotRTimeSetKey ()

	getWaitSetKey ()

	getWakeupListKey ()

	initAndPopPoolSlotList (RedisConnRef $conn, $now)

	registerAcquisitionTime (RedisConnRef $conn, $slot, $now)

	waitForSlotOrNotif ( $doWakeup)

Protected Member Functions inherited from PoolCounter
	hashKeyIntoSlots ( $type, $key, $slots)
	Given a key (any string) and the number of lots, returns a slot key (a prefix with a suffix integer from the [0..($slots-1)] range). More...

	onAcquire ()
	Update any lock tracking information when the lock is acquired. More...

	onRelease ()
	Update any lock tracking information when the lock is released. More...

	precheckAcquire ()
	Checks that the lock request is sane. More...

Protected Attributes
RedisConnRef	$conn

string	$keySha1
	SHA-1 of the key. More...

int	$lockTTL
	TTL for locks to expire (work should finish in this time) More...

LoggerInterface	$logger

int	$onRelease
	AWAKE_* constant. More...

RedisConnectionPool	$pool

HashRing	$ring

array	$serversByLabel
	(server label => host) map More...

string	$session
	Unique string to identify this process. More...

string	$slot
	Pool slot value. More...

int	$slotTime
	UNIX timestamp. More...

Protected Attributes inherited from PoolCounter
string	$key
	All workers with the same key share the lock. More...

int	$maxqueue
	If this number of workers are already working/waiting, fail instead of wait. More...

int	$slots = 0
	Maximum number of workers working on this task type, regardless of key. More...

float	$timeout
	Maximum time in seconds to wait for the lock. More...

int	$workers
	Maximum number of workers working on tasks with the same key simultaneously. More...

Static Protected Attributes
static PoolCounterRedis[]	$active = null
	List of active PoolCounterRedis objects in this script. More...

Detailed Description

Version of PoolCounter that uses Redis.

There are four main redis keys used to track each pool counter key:

poolcounter:l-slots-* : A list of available slot IDs for a pool.
poolcounter:z-renewtime-* : A sorted set of (slot ID, UNIX timestamp as score) used for tracking the next time a slot should be released. This is -1 when a slot is created, and is set when released (expired), locked, and unlocked.
poolcounter:z-wait-* : A sorted set of (slot ID, UNIX timestamp as score) used for tracking waiting processes (and wait time).
poolcounter:l-wakeup-* : A list pushed to for the sake of waking up processes when a any process in the pool finishes (lasts for 1ms). For a given pool key, all the redis keys start off non-existing and are deleted if not used for a while to prevent garbage from building up on the server. They are atomically re-initialized as needed. The "z-renewtime" key is used for detecting sessions which got slots but then disappeared. Stale entries from there have their timestamp updated and the corresponding slots freed up. The "z-wait" key is used for detecting processes registered as waiting but that disappeared. Stale entries from there are deleted and the corresponding slots are freed up. The worker count is included in all the redis key names as it does not vary within each $wgPoolCounterConf type and doing so handles configuration changes.

This class requires Redis 2.6 as it makes use Lua scripts for fast atomic operations. Also this should be on a server plenty of RAM for the working set to avoid evictions. Evictions could temporarily allow wait queues to double in size or temporarily cause pools to appear as full when they are not. Using volatile-ttl and bumping memory-samples in redis.conf can be helpful otherwise.

Since: 1.23

Definition at line 53 of file PoolCounterRedis.php.

Constructor & Destructor Documentation

◆ __construct()

PoolCounterRedis::__construct	(	$conf,
		$type,
		$key
	)

Parameters

array	$conf
string	$type	The class of actions to limit concurrency for (task type)
string	$key

Reimplemented from PoolCounter.

Definition at line 84 of file PoolCounterRedis.php.

References PoolCounter\$key, $type, MediaWiki\Logger\LoggerFactory\getInstance(), key, and RedisConnectionPool\singleton().

Member Function Documentation

◆ acquireForAnyone()

PoolCounterRedis::acquireForAnyone ( )

I want to do this task, but if anyone else does it instead, it's also fine for me.

I will read its cached data.

Returns: Status Value is one of Locked/Done/Error

Reimplemented from PoolCounter.

Definition at line 135 of file PoolCounterRedis.php.

References PoolCounter\precheckAcquire(), and waitForSlotOrNotif().

◆ acquireForMe()

PoolCounterRedis::acquireForMe ( )

I want to do this task and I need to do it myself.

Returns: Status Value is one of Locked/Error

Reimplemented from PoolCounter.

Definition at line 126 of file PoolCounterRedis.php.

References PoolCounter\precheckAcquire(), and waitForSlotOrNotif().

◆ getConnection()

PoolCounterRedis::getConnection ( )

protected

Returns: Status Uses RediConnRef as value on success

Definition at line 107 of file PoolCounterRedis.php.

References $conn, as, ArrayUtils\consistentHashSort(), key, StatusValue\newFatal(), and StatusValue\newGood().

Referenced by release(), and waitForSlotOrNotif().

◆ getSlotListKey()

PoolCounterRedis::getSlotListKey ( )

protected

Returns: string

Definition at line 396 of file PoolCounterRedis.php.

Referenced by initAndPopPoolSlotList(), registerAcquisitionTime(), release(), and waitForSlotOrNotif().

◆ getSlotRTimeSetKey()

PoolCounterRedis::getSlotRTimeSetKey ( )

protected

Returns: string

Definition at line 403 of file PoolCounterRedis.php.

Referenced by initAndPopPoolSlotList(), registerAcquisitionTime(), and release().

◆ getWaitSetKey()

PoolCounterRedis::getWaitSetKey ( )

protected

Returns: string

Definition at line 410 of file PoolCounterRedis.php.

Referenced by initAndPopPoolSlotList(), registerAcquisitionTime(), release(), and waitForSlotOrNotif().

◆ getWakeupListKey()

PoolCounterRedis::getWakeupListKey ( )

protected

Returns: string

Definition at line 417 of file PoolCounterRedis.php.

Referenced by release(), and waitForSlotOrNotif().

◆ initAndPopPoolSlotList()

PoolCounterRedis::initAndPopPoolSlotList	(	RedisConnRef	$conn,
			$now
	)

protected

Parameters

RedisConnRef	$conn
float	$now	UNIX timestamp

Returns: string|bool False on failure

Definition at line 292 of file PoolCounterRedis.php.

References $conn, a, add, and(), are, as, free, getSlotListKey(), getSlotRTimeSetKey(), getWaitSetKey(), If, in, is(), key, list, RedisConnRef\luaEval(), network, not, of, on, or, that, them, then, up, and use.

Referenced by waitForSlotOrNotif().

◆ registerAcquisitionTime()

PoolCounterRedis::registerAcquisitionTime	(	RedisConnRef	$conn,
			$slot,
			$now
	)

protected

Parameters

RedisConnRef	$conn
string	$slot
float	$now

Returns: int|bool False on failure

Definition at line 361 of file PoolCounterRedis.php.

References $conn, are, as, getSlotListKey(), getSlotRTimeSetKey(), getWaitSetKey(), If, is(), RedisConnRef\luaEval(), of, on, that, then, up, and use.

Referenced by waitForSlotOrNotif().

◆ release()

PoolCounterRedis::release ( )

I have successfully finished my task.

Lets another one grab the lock, and returns the workers waiting on acquireForAnyone()

Returns: Status Value is one of Released/NotLocked/Error

Reimplemented from PoolCounter.

Definition at line 144 of file PoolCounterRedis.php.

References $conn, $e, a, and(), any, are, as, by, captcha-old\count, e, free, from, getConnection(), getSlotListKey(), getSlotRTimeSetKey(), getWaitSetKey(), getWakeupListKey(), is(), list, RedisConnRef\luaEval(), made, needed(), StatusValue\newFatal(), StatusValue\newGood(), not, PoolCounter\NOT_LOCKED, of, on, PoolCounter\onRelease(), other(), PoolCounter\RELEASED, save, that, then, up, use, will, and work.

◆ releaseAll()

static PoolCounterRedis::releaseAll ( )

static

Try to make sure that locks get released (even with exceptions and fatals)

Definition at line 424 of file PoolCounterRedis.php.

References $e, and as.

◆ waitForSlotOrNotif()

PoolCounterRedis::waitForSlotOrNotif ( $doWakeup )

protected

Parameters

int $doWakeup AWAKE_* constant

Returns: Status

Definition at line 230 of file PoolCounterRedis.php.

References $conn, $e, $keys, $res, $session, $slot, $slotTime, AWAKE_ALL, PoolCounter\DONE, getConnection(), getSlotListKey(), getWaitSetKey(), getWakeupListKey(), initAndPopPoolSlotList(), PoolCounter\LOCK_HELD, PoolCounter\LOCKED, StatusValue\newFatal(), StatusValue\newGood(), PoolCounter\onAcquire(), PoolCounter\onRelease(), PoolCounter\QUEUE_FULL, registerAcquisitionTime(), and PoolCounter\TIMEOUT.

Referenced by acquireForAnyone(), and acquireForMe().

Member Data Documentation

◆ $active

PoolCounterRedis [] PoolCounterRedis::$active = null

staticprotected

List of active PoolCounterRedis objects in this script.

Definition at line 82 of file PoolCounterRedis.php.

◆ $conn

RedisConnRef PoolCounterRedis::$conn

protected

Definition at line 68 of file PoolCounterRedis.php.

Referenced by getConnection(), initAndPopPoolSlotList(), registerAcquisitionTime(), release(), and waitForSlotOrNotif().

◆ $keySha1

string PoolCounterRedis::$keySha1

protected

SHA-1 of the key.

Definition at line 63 of file PoolCounterRedis.php.

◆ $lockTTL

int PoolCounterRedis::$lockTTL

protected

TTL for locks to expire (work should finish in this time)

Definition at line 65 of file PoolCounterRedis.php.

◆ $logger

LoggerInterface PoolCounterRedis::$logger

protected

Definition at line 59 of file PoolCounterRedis.php.

◆ $onRelease

int PoolCounterRedis::$onRelease

protected

AWAKE_* constant.

Definition at line 72 of file PoolCounterRedis.php.

◆ $pool

RedisConnectionPool PoolCounterRedis::$pool

protected

Definition at line 57 of file PoolCounterRedis.php.

◆ $ring

HashRing PoolCounterRedis::$ring

protected

Definition at line 55 of file PoolCounterRedis.php.

◆ $serversByLabel

array PoolCounterRedis::$serversByLabel

protected

(server label => host) map

Definition at line 61 of file PoolCounterRedis.php.

◆ $session

string PoolCounterRedis::$session

protected

Unique string to identify this process.

Definition at line 74 of file PoolCounterRedis.php.

Referenced by waitForSlotOrNotif().

◆ $slot

string PoolCounterRedis::$slot

protected

Pool slot value.

Definition at line 70 of file PoolCounterRedis.php.

Referenced by waitForSlotOrNotif().

◆ $slotTime

int PoolCounterRedis::$slotTime

protected

UNIX timestamp.

Definition at line 76 of file PoolCounterRedis.php.

Referenced by waitForSlotOrNotif().

◆ AWAKE_ALL

const PoolCounterRedis::AWAKE_ALL = 2

Definition at line 79 of file PoolCounterRedis.php.

Referenced by waitForSlotOrNotif().

◆ AWAKE_ONE

const PoolCounterRedis::AWAKE_ONE = 1

Definition at line 78 of file PoolCounterRedis.php.

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

includes/poolcounter/PoolCounterRedis.php

Public Member Functions

Static Public Member Functions

Public Attributes

Protected Member Functions

Protected Attributes

Static Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ __construct()

Member Function Documentation

◆ acquireForAnyone()

◆ acquireForMe()

◆ getConnection()

◆ getSlotListKey()

◆ getSlotRTimeSetKey()

◆ getWaitSetKey()

◆ getWakeupListKey()

◆ initAndPopPoolSlotList()

◆ registerAcquisitionTime()

◆ release()

◆ releaseAll()

◆ waitForSlotOrNotif()

Member Data Documentation

◆ $active

◆ $conn

◆ $keySha1

◆ $lockTTL

◆ $logger

◆ $onRelease

◆ $pool

◆ $ring

◆ $serversByLabel

◆ $session

◆ $slot

◆ $slotTime

◆ AWAKE_ALL

◆ AWAKE_ONE