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-rw-r--r--includes/PoolCounter.php60
1 files changed, 32 insertions, 28 deletions
diff --git a/includes/PoolCounter.php b/includes/PoolCounter.php
index 182520e1..83ae0abe 100644
--- a/includes/PoolCounter.php
+++ b/includes/PoolCounter.php
@@ -1,11 +1,11 @@
<?php
/**
- * When you have many workers (threads/servers) giving service, and a
+ * When you have many workers (threads/servers) giving service, and a
* cached item expensive to produce expires, you may get several workers
* doing the job at the same time.
*
- * Given enough requests and the item expiring fast (non-cacheable,
+ * Given enough requests and the item expiring fast (non-cacheable,
* lots of edits...) that single work can end up unfairly using most (all)
* of the cpu of the pool. This is also known as 'Michael Jackson effect'
* since this effect triggered on the english wikipedia on the day Michael
@@ -15,16 +15,16 @@
* The PoolCounter provides semaphore semantics for restricting the number
* of workers that may be concurrently performing such single task.
*
- * By default PoolCounter_Stub is used, which provides no locking. You
+ * By default PoolCounter_Stub is used, which provides no locking. You
* can get a useful one in the PoolCounter extension.
*/
abstract class PoolCounter {
-
+
/* Return codes */
const LOCKED = 1; /* Lock acquired */
const RELEASED = 2; /* Lock released */
const DONE = 3; /* Another worker did the work for you */
-
+
const ERROR = -1; /* Indeterminate error */
const NOT_LOCKED = -2; /* Called release() with no lock held */
const QUEUE_FULL = -3; /* There are already maxqueue workers on this lock */
@@ -33,38 +33,38 @@ abstract class PoolCounter {
/**
* I want to do this task and I need to do it myself.
- *
+ *
* @return Locked/Error
*/
abstract function acquireForMe();
/**
- * I want to do this task, but if anyone else does it
+ * 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.
- *
+ *
* @return Locked/Done/Error
*/
abstract function acquireForAnyone();
/**
* I have successfully finished my task.
- * Lets another one grab the lock, and returns the workers
+ * Lets another one grab the lock, and returns the workers
* waiting on acquireForAnyone()
- *
+ *
* @return Released/NotLocked/Error
*/
abstract function release();
-
+
/**
* $key: All workers with the same key share the lock.
- * $workers: It wouldn't be a good idea to have more than this number of
+ * $workers: It wouldn't be a good idea to have more than this number of
* workers doing the task simultaneously.
- * $maxqueue: If this number of workers are already working/waiting,
+ * $maxqueue: If this number of workers are already working/waiting,
* fail instead of wait.
* $timeout: Maximum time in seconds to wait for the lock.
*/
protected $key, $workers, $maxqueue, $timeout;
-
+
/**
* Create a Pool counter. This should only be called from the PoolWorks.
*
@@ -80,10 +80,10 @@ abstract class PoolCounter {
}
$conf = $wgPoolCounterConf[$type];
$class = $conf['class'];
-
+
return new $class( $conf, $type, $key );
}
-
+
protected function __construct( $conf, $type, $key ) {
$this->key = $key;
$this->workers = $conf['workers'];
@@ -125,7 +125,7 @@ class PoolCounter_Stub extends PoolCounter {
*/
abstract class PoolCounterWork {
protected $cacheable = false; //Does this override getCachedWork() ?
-
+
/**
* Actually perform the work, caching it if needed.
*/
@@ -140,30 +140,34 @@ abstract class PoolCounterWork {
}
/**
- * A work not so good (eg. expired one) but better than an error
+ * A work not so good (eg. expired one) but better than an error
* message.
* @return mixed work result or false
*/
function fallback() {
return false;
}
-
+
/**
* Do something with the error, like showing it to the user.
*/
- function error( $status ) {
+ function error( $status ) {
return false;
}
/**
* Log an error
+ *
+ * @param $status Status
*/
function logError( $status ) {
wfDebugLog( 'poolcounter', $status->getWikiText() );
}
-
+
/**
* Get the result of the work (whatever it is), or false.
+ * @param $skipcache bool
+ * @return bool|mixed
*/
function execute( $skipcache = false ) {
if ( $this->cacheable && !$skipcache ) {
@@ -183,7 +187,7 @@ abstract class PoolCounterWork {
$result = $this->doWork();
$this->poolCounter->release();
return $result;
-
+
case PoolCounter::DONE:
$result = $this->getCachedWork();
if ( $result === false ) {
@@ -193,27 +197,27 @@ abstract class PoolCounterWork {
return $this->execute( true );
}
return $result;
-
+
case PoolCounter::QUEUE_FULL:
case PoolCounter::TIMEOUT:
$result = $this->fallback();
-
+
if ( $result !== false ) {
return $result;
}
/* no break */
-
+
/* These two cases should never be hit... */
case PoolCounter::ERROR:
default:
$errors = array( PoolCounter::QUEUE_FULL => 'pool-queuefull', PoolCounter::TIMEOUT => 'pool-timeout' );
-
- $status = Status::newFatal( isset($errors[$status->value]) ? $errors[$status->value] : 'pool-errorunknown' );
+
+ $status = Status::newFatal( isset( $errors[$status->value] ) ? $errors[$status->value] : 'pool-errorunknown' );
$this->logError( $status );
return $this->error( $status );
}
}
-
+
function __construct( $type, $key ) {
$this->poolCounter = PoolCounter::factory( $type, $key );
}