Version of PoolCounter that uses Redis. More...

Inheritance diagram for PoolCounterRedis:

Collaboration diagram for PoolCounterRedis:

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

	acquireForAnyone ()

	acquireForMe ()

	release ()

Public Member Functions inherited from PoolCounter
	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...

	getKey ()

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

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
	__construct ($conf, $type, $key)

	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 54 of file PoolCounterRedis.php.

Constructor & Destructor Documentation

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

Definition at line 85 of file PoolCounterRedis.php.

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

Member Function Documentation

PoolCounterRedis::acquireForAnyone ( )

Definition at line 136 of file PoolCounterRedis.php.

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

PoolCounterRedis::acquireForMe ( )

Definition at line 127 of file PoolCounterRedis.php.

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

PoolCounterRedis::getConnection ( )

protected

Returns: Status Uses RediConnRef as value on success

Definition at line 108 of file PoolCounterRedis.php.

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

Referenced by release(), and waitForSlotOrNotif().

PoolCounterRedis::getSlotListKey ( )

protected

Returns: string

Definition at line 397 of file PoolCounterRedis.php.

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

PoolCounterRedis::getSlotRTimeSetKey ( )

protected

Returns: string

Definition at line 404 of file PoolCounterRedis.php.

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

PoolCounterRedis::getWaitSetKey ( )

protected

Returns: string

Definition at line 411 of file PoolCounterRedis.php.

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

PoolCounterRedis::getWakeupListKey ( )

protected

Returns: string

Definition at line 418 of file PoolCounterRedis.php.

Referenced by release(), and waitForSlotOrNotif().

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

protected

Parameters

RedisConnRef	$conn
float	$now	UNIX timestamp

Returns: string|bool False on failure

Definition at line 293 of file PoolCounterRedis.php.

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

Referenced by waitForSlotOrNotif().

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

protected

Parameters

RedisConnRef	$conn
string	$slot
float	$now

Returns: int|bool False on failure

Definition at line 362 of file PoolCounterRedis.php.

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

Referenced by waitForSlotOrNotif().

PoolCounterRedis::release ( )

Definition at line 145 of file PoolCounterRedis.php.

References $e, $status, and(), are, as, by, 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, set, that, the, then, up, use, will, and work().

static PoolCounterRedis::releaseAll ( )

static

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

Definition at line 425 of file PoolCounterRedis.php.

References $e, and as.

PoolCounterRedis::waitForSlotOrNotif ( $doWakeup )

protected

Parameters

int $doWakeup AWAKE_* constant

Returns: Status

Definition at line 231 of file PoolCounterRedis.php.

References $e, $keys, $res, $session, $slot, $slotTime, $status, 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

PoolCounterRedis [] PoolCounterRedis::$active = null

staticprotected

List of active PoolCounterRedis objects in this script.

Definition at line 83 of file PoolCounterRedis.php.

RedisConnRef PoolCounterRedis::$conn

protected

Definition at line 69 of file PoolCounterRedis.php.

Referenced by getConnection().

string PoolCounterRedis::$keySha1

protected

SHA-1 of the key.

Definition at line 64 of file PoolCounterRedis.php.

int PoolCounterRedis::$lockTTL

protected

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

Definition at line 66 of file PoolCounterRedis.php.

LoggerInterface PoolCounterRedis::$logger

protected

Definition at line 60 of file PoolCounterRedis.php.

int PoolCounterRedis::$onRelease

protected

AWAKE_* constant.

Definition at line 73 of file PoolCounterRedis.php.

RedisConnectionPool PoolCounterRedis::$pool

protected

Definition at line 58 of file PoolCounterRedis.php.

HashRing PoolCounterRedis::$ring

protected

Definition at line 56 of file PoolCounterRedis.php.

array PoolCounterRedis::$serversByLabel

protected

(server label => host) map

Definition at line 62 of file PoolCounterRedis.php.

string PoolCounterRedis::$session

protected

Unique string to identify this process.

Definition at line 75 of file PoolCounterRedis.php.

Referenced by waitForSlotOrNotif().

string PoolCounterRedis::$slot

protected

Pool slot value.

Definition at line 71 of file PoolCounterRedis.php.

Referenced by waitForSlotOrNotif().

int PoolCounterRedis::$slotTime

protected

UNIX timestamp.

Definition at line 77 of file PoolCounterRedis.php.

Referenced by waitForSlotOrNotif().

const PoolCounterRedis::AWAKE_ALL = 2

Definition at line 80 of file PoolCounterRedis.php.

const PoolCounterRedis::AWAKE_ONE = 1

Definition at line 79 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

Member Function Documentation

Member Data Documentation