分享PHP-pcntl 实现多进程代码

PHP使用PCNTL系列的函数也能做到多进程处理一个事务。比如我需要从数据库中获取80w条的数据，再做一系列后续的处理，这个时候，用单进程？你可以等到明年今天了。。。所以应该使用pcntl函数了。

下面我们来看个实例

代码

<?php
$arChildId = array();

for($i = 0; $i < 10; $i++)
{
$iPid = pcntl_fork();
if($iPid == -1)
{
  die('can\'t be forked.');
}

if($iPid)
{
  # 主进程逻辑
  $arChildId[] = $iPid;
}
else
  {
  # 子进程逻辑
  $iPid = posix_getpid(); # 获取子进程的ID
  $iSeconds = rand(5, 30);
  echo '* Process '. $iPid. ' was created, and Executed, and Sleep '. $iSeconds. PHP_EOL;
  excuteProcess($iPid, $iSeconds);
  exit();
}
}

while(count($arChildId) > 0)
{
foreach($arChildId as $iKey=> $iPid)
{
  $res = pcntl_waitpid($iPid, $status, WNOHANG);

  if($res == -1 || $res > 0)
  {
    unset($arChildId[$iKey]);
    echo '* Sub process: '. $iPid. ' exited with '. $status. PHP_EOL;
  }
}
}

# 子进程执行的逻辑
function excuteProcess($iPid, $iSeconds)
{
file_put_contents('./log/'.$iPid.'.log', $iPid.PHP_EOL, FILE_APPEND);
sleep($iSeconds);
}
?>

运行结果

* Process 16163 was created, and Executed, and Sleep 11
* Process 16164 was created, and Executed, and Sleep 21
* Process 16165 was created, and Executed, and Sleep 24
* Process 16166 was created, and Executed, and Sleep 27
* Process 16167 was created, and Executed, and Sleep 8
* Process 16168 was created, and Executed, and Sleep 14
* Process 16169 was created, and Executed, and Sleep 14
* Process 16170 was created, and Executed, and Sleep 26
* Process 16171 was created, and Executed, and Sleep 20
* Process 16172 was created, and Executed, and Sleep 21
* Sub process: 16167 exited with 0
* Sub process: 16163 exited with 0
* Sub process: 16169 exited with 0
* Sub process: 16168 exited with 0
* Sub process: 16171 exited with 0
* Sub process: 16164 exited with 0
* Sub process: 16172 exited with 0
* Sub process: 16165 exited with 0
* Sub process: 16170 exited with 0
* Sub process: 16166 exited with 0