This article mainly introduces how to use PHP’s memcache class (memcache queue). Friends in need can refer to it
memcacheQueue.class.php
The code is as follows:
add('1asdf');
* $obj->getQueueLength();
* $obj->read(10);
* $obj->get(8);
*/
class memcacheQueue{
public static $client; //memcache client connection
public $access; //Whether the queue can be updated
private $expire; //Expiration time, seconds, 1~2592000, that is, within 30 days
private $sleepTime; //Waiting time for unlocking, microseconds
private $queueName; //Queue name, unique value
private $retryNum; //Number of retries, = 10 * theoretical concurrency number
public $currentHead; //Current team head value
public $currentTail; //Current tail value
const MAXNUM = 20000; //Maximum number of queues, the recommended upper limit is 10K
const HEAD_KEY = '_lkkQueueHead_'; //The first key of the queue
const TAIL_KEY = '_lkkQueueTail_'; //queue tail key
const VALU_KEY = '_lkkQueueValu_'; //queue value key
const LOCK_KEY = '_lkkQueueLock_'; //Queue lock key
/*** Constructor
* @param string $queueName Queue name
* @param int $expire expiration time
* @param array $config memcache configuration
*
* @return
*/
public function __construct($queueName ='',$expire=0,$config =''){
if(empty($config)){
Self::$client = memcache_pconnect('127.0.0.1',11211);
}elseif(is_array($config)){//array('host'=>'127.0.0.1','port'=>'11211')
self::$client = memcache_pconnect($config['host'],$config['port']);
}elseif(is_string($config)){//"127.0.0.1:11211"
$tmp = explode(':',$config);
$conf['host'] = isset($tmp[0]) ? $tmp[0] : '127.0.0.1';
$conf['port'] = isset($tmp[1]) ? $tmp[1] : '11211';
Self::$client = memcache_pconnect($conf['host'],$conf['port']);
}
if(!self::$client) return false;
ignore_user_abort(true);//When the client disconnects, allow execution to continue
set_time_limit(0);//Cancel the upper limit of script execution delay
$this->access = false;
$this->sleepTime = 1000;
$expire = empty($expire) ? 3600 : intval($expire)+1;
$this->expire = $expire;
$this->queueName = $queueName;
$this->retryNum = 1000;
$this->head_key = $this->queueName . self::HEAD_KEY;
$this->tail_key = $this->queueName . self::TAIL_KEY;
$this->lock_key = $this->queueName . self::LOCK_KEY;
$this->_initSetHeadNTail();
}
/*** Initialize and set the head and tail values of the queue
*/
private function _initSetHeadNTail(){
//The value at the head of the current queue
$this->currentHead = memcache_get(self::$client, $this->head_key);
if($this->currentHead === false) $this->currentHead =0;
//The value at the end of the current queue
$this->currentTail = memcache_get(self::$client, $this->tail_key);
if($this->currentTail === false) $this->currentTail =0;
}
/*** When taking out an element, change the value at the head of the queue
* @param int $step step value
*/
private function _changeHead($step=1){
$this->currentHead += $step;
memcache_set(self::$client, $this->head_key,$this->currentHead,false,$this->expire);
}
/*** When adding an element, change the value at the end of the queue
* @param int $step step value
* @param bool $reverse Whether to reverse
* @return null
*/
private function _changeTail($step=1, $reverse =false){
if(!$reverse){
$this->currentTail += $step;
}else{
$this->currentTail -= $step;
}
memcache_set(self::$client, $this->tail_key,$this->currentTail,false,$this->expire);
}
/*** Whether the queue is empty
* @return bool
*/
private function _isEmpty(){
return (bool)($this->currentHead === $this->currentTail);
}
/*** Is the queue full?
* @return bool
*/
private function _isFull(){
$len = $this->currentTail - $this->currentHead;
return (bool)($len === self::MAXNUM);
}
/*** Queue locking
*/
private function _getLock(){
if($this->access === false){
while(!memcache_add(self::$client, $this->lock_key, 1, false, $this->expire) ){
usleep($this->sleepTime);
@$i++;
if($i > $this->retryNum){//尝试等待N次
return false;
break;
}
}
$this->_initSetHeadNTail();
return $this->access = true;
}
return $this->access;
}
/*** Queue unlocking
*/
private function _unLock(){
memcache_delete(self::$client, $this->lock_key, 0);
$this->access = false;
}
/*** Get the length of the current queue
* This length is the theoretical length, some elements are lost due to expiration, the real length
http://www.bkjia.com/PHPjc/746591.htmlwww.bkjia.comtruehttp://www.bkjia.com/PHPjc/746591.htmlTechArticle这篇文章主要介绍了php的memcache类的使用方法(memcache队列),需要的朋友可以参考下 memcacheQueue.class.php代码如下:?php/*** PHP memcache 队列类* @aut...
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