How to solve PHP high concurrency problems?

In highly concurrent scenarios, PHP servers often encounter performance bottlenecks. In this article, we will introduce several common ways to solve PHP's high concurrency problem, including the use of caching, the use of PHP-FPM, the use of asynchronous processing and so on.

1. Use of caches

Using caching is one of the common ways to improve server performance. By caching commonly used data in memory, you can avoid the need to read data from the database for each request, thus reducing the pressure on the database and improving the server's responsiveness. In PHP, data caching can be implemented using caching technologies such as Redis and Memcached.

The following is sample code for caching with Redis:

phpCopy code$redis = new Redis();
$redis->connect('127.0.0.1', 6379);
$data = $redis->get('key');
if (!$data) {
  $data = getDataFromDB();
  $redis->setex('key', 3600, $data);
}

In the above code, $redis->connect() method is used to connect to the Redis server, and $redis->get() and $redis->setex() methods are used to read and write cached data.

2. Using PHP-FPM

PHP-FPM (FastCGI Process Manager) is a PHP FastCGI process manager that improves the concurrency of PHP. PHP-FPM can distribute requests to multiple PHP sub-processes to increase the concurrency of the server.

On Ubuntu systems, PHP-FPM can be installed using the following command:

arduinoCopy codesudo apt-get install php-fpm

After installation, you need to configure PHP-FPM in either nginx or Apache. nginx, for example, can be configured by adding the following code to the nginx configuration file:

perlCopy codelocation ~ \.php$ {
  fastcgi_pass unix:/var/run/php/php7.4-fpm.sock;
  fastcgi_index index.php; fastcgi_param SCRIPT.4-fpm.sock; fastcgi_index
  fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
  include fastcgi_params;
}

In the above code, fastcgi_pass specifies the listening address of the PHP-FPM process and SCRIPT_FILENAME is used to specify the filename of the PHP script.

3. Use of asynchronous processing

In highly concurrent scenarios, the use of asynchronous processing can significantly improve the performance of the server. asynchronous processing can be implemented in PHP using tools such as ReactPHP, Swoole, and so on.

3.1 Using ReactPHP

ReactPHP is an event-driven asynchronous programming framework that can be used to write high-performance server applications. Asynchronous processing, such as reading and writing databases, network communication, etc., can be implemented very easily with ReactPHP.

The following is sample code that implements asynchronous processing using ReactPHP:

phpCopy code$loop = React\EventLoop\Factory::create();
$connector = new React\Socket\Connector($loop);
$connector->connect('tcp://127.0.0.1:80')->then(function (React\Socket\ConnectionInterface $connection) {
    $connection->write("GET /

3.2 Using Swoole

Swoole is a high-performance PHP asynchronous network communication framework , you can implement asynchronous IO , coprocessing , multiprocessing and other features , very suitable for high-concurrency scenarios in the application development .

The following is sample code that implements asynchronous processing using Swoole:

phpCopy code$server = new Swoole\Http\Server("127.0.0.1", 9501);
$server->on("request", function (Swoole\Http\Request $request, Swoole\Http\Response $response) {
    $response->header("Content-Type", "text/plain");
    $response->end("Hello World\n");
});
$server->start();

In the above code, the Swoole\Http\Server class is used to create the HTTP server and the $server->on() method is used to register the event handler function.

summarize

These are just a few common ways to solve PHP's high concurrency problems. The use of caching, PHP-FPM and asynchronous processing can all improve server performance, and you should choose the right solution for your specific scenario. In practice, you can also combine several methods to improve server performance.