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PoolCounterRedis Class Reference

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 53 of file PoolCounterRedis.php.

Constructor & Destructor Documentation

◆ __construct()

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

Member Function Documentation

◆ acquireForAnyone()

PoolCounterRedis::acquireForAnyone ( )

Definition at line 137 of file PoolCounterRedis.php.

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

◆ acquireForMe()

PoolCounterRedis::acquireForMe ( )

Definition at line 128 of file PoolCounterRedis.php.

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

◆ getConnection()

PoolCounterRedis::getConnection ( )
protected
Returns
Status Uses RediConnRef as value on success

Definition at line 109 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 398 of file PoolCounterRedis.php.

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

◆ getSlotRTimeSetKey()

PoolCounterRedis::getSlotRTimeSetKey ( )
protected
Returns
string

Definition at line 405 of file PoolCounterRedis.php.

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

◆ getWaitSetKey()

PoolCounterRedis::getWaitSetKey ( )
protected
Returns
string

Definition at line 412 of file PoolCounterRedis.php.

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

◆ getWakeupListKey()

PoolCounterRedis::getWakeupListKey ( )
protected
Returns
string

Definition at line 419 of file PoolCounterRedis.php.

Referenced by release(), and waitForSlotOrNotif().

◆ initAndPopPoolSlotList()

PoolCounterRedis::initAndPopPoolSlotList ( RedisConnRef  $conn,
  $now 
)
protected
Parameters
RedisConnRef$conn
float$nowUNIX timestamp
Returns
string|bool False on failure

Definition at line 294 of file PoolCounterRedis.php.

References add, and(), are, as, free, getSlotListKey(), getSlotRTimeSetKey(), getWaitSetKey(), in, is, key, list, RedisConnRef\luaEval(), network, 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 363 of file PoolCounterRedis.php.

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

Referenced by waitForSlotOrNotif().

◆ release()

◆ releaseAll()

static PoolCounterRedis::releaseAll ( )
static

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

Definition at line 426 of file PoolCounterRedis.php.

References $e, as, and null.

◆ waitForSlotOrNotif()

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().

◆ $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.

◆ 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: