Example of PHP pcntl multi-process usage

This article mainly introduces the usage of pcntl multi-process in PHP, and analyzes the usage skills of pcntl to operate multi-process, which is of great practical value, you can refer to the following example to describe the use of pcntl multi-process in PHP. Share it with you for your reference. The specific analysis is as follows:

PHP uses functions of the PCNTL series to process a transaction in multiple processes. For example, if I need to retrieve million pieces of data from the database and perform a series of subsequent processing, how can I use a single process? You can wait until next year. So we should use the pcntl function.

Suppose I want to start 20 processes and divide the data from 1 to 80 W into 20 parts. The main process will exit after all the sub-processes are completed:

$max = 800000;$workers = 20;$pids = array();for($i = 0; $i < $workers; $i++){  $pids[$i] = pcntl_fork();  switch ($pids[$i]) {    case -1:      echo "fork error : {$i} \r\n";      exit;    case 0:      $param = array(        'lastid' => $max / $workers * $i,        'maxid' => $max / $workers * ($i+1),      );      $this->executeWorker($input, $output, $param);      exit;    default:      break;  }}foreach ($pids as $i => $pid) {  if($pid) {    pcntl_waitpid($pid, $status);  }}

Here, when pcntl_fork comes out, a pid value will be returned. this pid is 0 in the sub-process, and the pid in the parent process is the sub-process pid (> 0 ), if the pid is-1, the fork has an error.

With a $ pids array, the main process can be completed after all processes are completed.

I hope this article will help you with php programming.

For more articles about examples of pcntl multi-process usage in PHP, refer to the Chinese PHP website!