php Pthread 多线程 (六) Pool类 线程池
发布时间:2020-05-25 08:14:06 所属栏目:PHP 来源:互联网
导读:Pool对象是多个Worker对象的容器,同时也是它们的控制器,对Worker功能更高抽象。 比如Worker是河,而线程是运行在河里的船。Pool则是管理着多条河。 lt;?php //继承Col
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Pool对象是多个Worker对象的容器,同时也是它们的控制器,对Worker功能更高抽象。 比如Worker是河,而线程是运行在河里的船。Pool则是管理着多条河。 <?php
//继承Collectable垃圾收集类,好让Pool::collect进行收集
class Sql extends Collectable {
private $sql = '';
private $data = array();
public function __construct($sql) {
$this->sql = $sql;
}
public function run() {
$db = $this->worker->getDb();
$res = mysql_query($this->sql,$db);
$tmp = array();
while($row = mysql_fetch_assoc($res)) {
//这里不能使用$this->data[] = $row;这种方式。
$tmp[] = $row;
}
$this->data = $tmp;
//这里工作完后,设置为垃圾
//在Pool::collect中isGarbage()判断时则为真
$this->setGarbage();
}
public function getData() {
return $this->data;
}
}
class SqlWorker extends Worker {
protected static $db = null;
public function getDb() {
if(!self::$db) {
self::$db = mysql_connect('127.0.0.1','root','');
mysql_select_db('test',self::$db);
}
return self::$db;
}
}
//这里创建5个Worker对象的Pool线程池
$pool = new Pool(5,'SqlWorker');
//我们创建20个Sql线程对象,并提交到Pool的Worker中
$sqls = array();
for($ix = 0; $ix < 20; ++$ix) {
$sql = new Sql("select * from test order by id limit {$ix},1");
$sqls[] = $sql;
//$pool->submit($sql);不要在这里submit
}
//注意,这里循环提交$sql
//如果把$pool->submit放到前面的for循环内,会出现一个错误
//第一个Sql对象的sql语句会跟最后一个相同,导致结果出现问题
foreach($sqls as $sql) {
//这里的submit方法有问题,它会修改$sqls
//导致第一个Sql对象与最后一个相同
//不知是不是BUG
$pool->submit($sql);
}
//等待队列中执行完成
$pool->shutdown();
$ret = array();
foreach($sqls as $sql) {
$ret[] = $sql->getData();
}
file_put_contents('ret.txt',var_export($ret,true));
//回收已完成的对象
$pool->collect(function($sql){
return $sql->isGarbage();
});
array (
0 =>
array (
0 =>
array (
'id' => '20','name' => 'mmm',),1 =>
array (
0 =>
array (
'id' => '2','name' => '222',2 =>
array (
0 =>
array (
'id' => '3','name' => '333',3 =>
array (
0 =>
array (
'id' => '4','name' => '444',4 =>
array (
0 =>
array (
'id' => '5','name' => '555',5 =>
array (
0 =>
array (
'id' => '6','name' => '666',6 =>
array (
0 =>
array (
'id' => '7','name' => '777',7 =>
array (
0 =>
array (
'id' => '8','name' => '888',8 =>
array (
0 =>
array (
'id' => '9','name' => '999',9 =>
array (
0 =>
array (
'id' => '10','name' => 'aaa',10 =>
array (
0 =>
array (
'id' => '11','name' => 'bbb',11 =>
array (
0 =>
array (
'id' => '12','name' => 'ccc',12 =>
array (
0 =>
array (
'id' => '13','name' => 'ddd',13 =>
array (
0 =>
array (
'id' => '14','name' => 'eee',14 =>
array (
0 =>
array (
'id' => '15','name' => 'fff',15 =>
array (
0 =>
array (
'id' => '16','name' => 'ggg',16 =>
array (
0 =>
array (
'id' => '17','name' => 'vvv',17 =>
array (
0 =>
array (
'id' => '18','name' => 'hhh',18 =>
array (
0 =>
array (
'id' => '19','name' => 'nnn',19 =>
array (
0 =>
array (
'id' => '20',)
从结果可以看出,第一条记录跟最后一条是相同的,再没有pool->submit之前$sqls数组中的对象都是正确的,submit之后第一个对象的数据就改变了,不知道是不是pthreads的BUG。
上述代码我们通过创建一个包含5个SqlWorker对象的pool,然后创建20个Sql对象加入到pool中。
当然我们的Sql类并不一定非要继承自Collectable类,我们也可自定义判断什么时候可回收。
<?php
//继承Threaded类,Threaded提供了隐式的线程安全机制
//这个对象中的所有操作都是线程安全的
class MyWork extends Threaded {
private $name = '';
private $do = false;
private $data = '';
public function __construct($name) {
$this->name = $name;
}
public function run() {
$this->data = "{$this->name} run... in thread [" . $this->worker->getName() . "] rn";
//通过do来判断是否完成
//如果为true,则让Pool::collect回收
$this->do = true;
}
public function isDo() {
return $this->do;
}
public function getData() {
return $this->data;
}
}
class MyWorker extends Worker {
public static $name = 0;
public function __construct() {
self::$name++;
}
public function run() {
}
public function getName() {
return self::$name;
}
}
$pool = new Pool(5,'MyWorker');
$works = array();
for($ix = 0; $ix < 20; ++$ix) {
$work = new MyWork($ix);
$works[] = $work;
}
foreach($works as $work) {
$pool->submit($work);
}
$pool->shutdown();
foreach($works as $work) {
echo $work->getData();
}
//回收已完成的对象
$pool->collect(function($work){
//我们通过自定义函数isDo来判断对象是否执行完毕
return $work->isDo();
});
执行结果如下:
19 run... in thread [5] 1 run... in thread [2] 2 run... in thread [3] 3 run... in thread [4] 4 run... in thread [5] 5 run... in thread [1] 6 run... in thread [2] 7 run... in thread [3] 8 run... in thread [4] 9 run... in thread [5] 10 run... in thread [1] 11 run... in thread [2] 12 run... in thread [3] 13 run... in thread [4] 14 run... in thread [5] 15 run... in thread [1] 16 run... in thread [2] 17 run... in thread [3] 18 run... in thread [4] 19 run... in thread [5]第一条记录为什么会有问题,前面我已经说过了。这里我们看20个MyWork对象,它们顺序的加入到5个MyWorker对象中,如果第一条记录没有问题的话,它们分别加入到1,2,3,4,5的MyWorker中,然后远行run方法。 (编辑:安卓应用网) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |
