How to use coroutines to implement high-concurrency swoole_sntp function in Swoole

Swoole is a high-performance PHP coroutine framework with features such as coroutines, asynchronous IO, high performance, and high concurrency. It is very suitable for developing network services. Among them, the swoole_sntp function is used to synchronize server time and can play a very important role in development. In this article, we will introduce how to use coroutines to implement high-concurrency swoole_sntp function in Swoole.

Swoole_sntp introduction

The Swoole_sntp function is a function in the Swoole framework that synchronizes server time. It can send an NTP protocol request to a specified network time server and then obtain the time of the server. information. Its function is defined as follows:

bool swoole_sntp(string $server, float $timeout = 1.0, float $offset = null);

Among them, the $server parameter is the address of the specified time server, the $timeout parameter is the timeout time, and the $offset parameter is the time difference between local and network time, which does not need to be specified.

Using coroutines

When using the Swoole_sntp function, it is often necessary to request time information from multiple time servers, and the request needs to be completed within a certain period of time. In this case, using coroutines can achieve high concurrency and improve request speed.

Coroutines are lightweight threads that can execute multiple tasks simultaneously in the same process, avoiding the performance loss caused by multi-threaded context switching. In Swoole, coroutines can be used to implement simultaneous requests to multiple time servers.

The following is a sample code that uses coroutines to implement high-concurrency swoole_sntp function:

<?php

use SwooleCoroutine;

function sntp($server, $timeout = 1.0, $offset = null)
{
    $cli = new CoroutineHttpClient($server, 80);
    $cli->setDefer();

    $cli->execute('/');

    if ($cli->statusCode !== 200) {
        return false;
    }

    $response = $cli->body;

    $ts = unpack('N12', substr($response, 0, 48));
    $ts = round(($ts[9] * 1.0) + ($ts[10] * 1.0 / 4294967296.0) - 2208988800.0);

    $cli->close();

    return $ts;
}

$serverList = ['cn.pool.ntp.org', 'tw.pool.ntp.org', 'jp.pool.ntp.org'];

$sntp = function ($server) {
    $cli = new CoroutineHttpClient($server, 80);
    $cli->setDefer();

    $cli->execute('/');

    if ($cli->statusCode !== 200) {
        return false;
    }

    $response = $cli->body;

    $ts = unpack('N12', substr($response, 0, 48));
    $ts = round(($ts[9] * 1.0) + ($ts[10] * 1.0 / 4294967296.0) - 2208988800.0);

    $cli->close();

    return $ts;
};

$results = [];
foreach ($serverList as $server) {
    Coroutine::create(function () use ($server, &$results, $sntp) {
        $results[$server] = $sntp($server);
    });
}

while (count($results) < count($serverList)) {
    Coroutine::sleep(0.1);
}

print_r($results);

In the above code, a function named sntp is first defined to request the time server and return the time information. Next, an anonymous function named $sntp is defined, which is also used to request the time server and return time information. In the loop, use Coroutine::create to create a new coroutine, use the $sntp function to request the time server, and save the results in the $results array. Finally, use a while loop to wait for all coroutines to complete and output all time information.

Summary

Through the above introduction, you should have a preliminary understanding of how to use coroutines to implement the highly concurrent swoole_sntp function in Swoole. Coroutines are a very important feature in the Swoole framework. They can greatly improve the performance and concurrency of network services and are worthy of in-depth study and practice by developers.

The above is the detailed content of How to use coroutines to implement high-concurrency swoole_sntp function in Swoole. For more information, please follow other related articles on the PHP Chinese website!