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WordPress多线程讲解

WordPress运行在PHP环境中，而PHP传统上并不原生支持真正的多线程。然而，通过特定扩展和技术手段，我们可以实现类似多线程的并发处理能力。

1. 安装PHP并行扩展

# 安装pthreads扩展
pecl install pthreads

# 安装parallel扩展(PHP 7.2+)
pecl install parallel

2. 服务器配置要求

在php.ini中启用必要配置：

[parallel]
parallel.enable=1
parallel.io.pool_size=4

WordPress多线程实现方案

1. 后台任务处理器

使用WP-Cron结合多进程技术：

class Async_Task_Handler {
    private static $instance;
    private $processes = [];
    
    public static function get_instance() {
        if (null === self::$instance) {
            self::$instance = new self();
        }
        return self::$instance;
    }
    
    public function dispatch_task($callable, $args = []) {
        $process_id = uniqid();
        $this->processes[$process_id] = [
            'status' => 'queued',
            'start_time' => time()
        ];
        
        wp_schedule_single_event(time(), 'async_task_hook', [$process_id, $callable, $args]);
        
        return $process_id;
    }
    
    public function run_task($process_id, $callable, $args) {
        if (is_callable($callable)) {
            $this->processes[$process_id]['status'] = 'running';
            $result = call_user_func_array($callable, $args);
            $this->processes[$process_id] = [
                'status' => 'completed',
                'result' => $result,
                'end_time' => time()
            ];
        }
    }
}

add_action('async_task_hook', ['Async_Task_Handler', 'run_task'], 10, 3);

2. 并行HTTP请求

使用Guzzle实现并发HTTP请求：

use GuzzleHttp\Client;
use GuzzleHttp\Promise;

function concurrent_requests($urls) {
    $client = new Client(['timeout' => 5.0]);
    $promises = [];
    
    foreach ($urls as $url) {
        $promises[$url] = $client->getAsync($url);
    }
    
    $results = Promise\Utils::settle($promises)->wait();
    
    $responses = [];
    foreach ($results as $url => $result) {
        $responses[$url] = $result['value']->getBody()->getContents();
    }
    
    return $responses;
}

多线程应用场景

1. 批量图片处理

使用Imagick并行处理上传图片：

class Image_Processor {
    private $workers = [];
    
    public function __construct($worker_count = 4) {
        for ($i = 0; $i < $worker_count; $i++) {
            $this->workers[] = new Worker();
        }
    }
    
    public function process_images($images) {
        $tasks = [];
        foreach ($images as $image) {
            $worker = $this->get_available_worker();
            $tasks[] = $worker->submit(new Image_Task($image));
        }
        
        $results = [];
        foreach ($tasks as $task) {
            $results[] = $task->get_result();
        }
        
        return $results;
    }
    
    private function get_available_worker() {
        // 实现简单的worker分配逻辑
    }
}

2. 数据导入导出

并行处理大数据量：

function parallel_data_import($data_chunks) {
    $runtime = new \parallel\Runtime();
    $futures = [];
    
    foreach ($data_chunks as $chunk) {
        $futures[] = $runtime->run(function($chunk) {
            $results = [];
            foreach ($chunk as $item) {
                $results[] = wp_insert_post($item);
            }
            return $results;
        }, [$chunk]);
    }
    
    $imported_ids = [];
    foreach ($futures as $future) {
        $imported_ids = array_merge($imported_ids, $future->value());
    }
    
    return $imported_ids;
}