search
HomeBackend DevelopmentPHP TutorialDetailed explanation of PHP coroutines: Go + Chan + Defer

Swoole4 provides a powerful CSP# for the PHP language ##Coroutine programming mode. The bottom layer provides 3 keywords, which can easily implement various functions. The PHP coroutine

syntax provided by
  • Swoole4 is borrowed from Golang, and I would like to express my sincere thanks to the GO development team Tribute
  • PHP SwooleCoroutines can complement Golang very well. Golang: static language, rigorous, powerful and good in performance, PHP Swoole: dynamic language, flexible, simple and easy to use
This article is based on
Swoole-4.2. 9 and PHP-7.2.9 version
Keywords

  • go: Create a coroutine
  • chan: Create a channel
  • defer: Delay task, executed when the coroutine exits, first in, last out
This The underlying implementation of

3 functions are all memory operations, without any IO resource consumption. Just like PHPArray is very cheap. You can use it directly if necessary. This is different from socket and file operations. The latter need to apply for ports and file descriptors from the operating system, and reading and writing may cause blocking IO waiting.

Recommended learning: "

PHP Video Tutorial"

Coroutine Concurrency

Use the

go function to make a Functions are executed concurrently. During the programming process, if a certain piece of logic can be executed concurrently, it can be placed in the gocoroutine for execution.

Sequential execution

function test1() 
{
    sleep(1);
    echo "b";
}
    
function test2() 
{
    sleep(2);
    echo "c";
}

test1();
test2();

Execution results:

htf@LAPTOP-0K15EFQI:~$ time php b1.php
bc
real    0m3.080s
user    0m0.016s
sys     0m0.063s
htf@LAPTOP-0K15EFQI:~$

In the above code,

test1 and test2 will be executed sequentially, which requires3It takes seconds to complete the execution.

Concurrent execution

Using

go to create a coroutine can make the two functions test1 and test2 become concurrent executions .

Swoole\Runtime::enableCoroutine();

go(function () 
{
    sleep(1);
    echo "b";
});
    
go(function () 
{
    sleep(2);
    echo "c";
});
Swoole\Runtime::enableCoroutine()The function is to use the stream, sleep,# provided by PHP ##pdo, mysqli, redis and other functions switch from synchronous blocking to asynchronous coroutine IOExecution results:
bchtf@LAPTOP-0K15EFQI:~$ time php co.php
bc
real    0m2.076s
user    0m0.000s
sys     0m0.078s
htf@LAPTOP-0K15EFQI:~$

You can see that it only took

2

seconds to complete the execution.

The sequential execution time is equal to the sum of the execution time of all tasks:
    t1 t2 t3...
  • The concurrent execution time is equal to the execution time of all tasks The maximum value:
  • max(t1, t2, t3, ...)
  • Coroutine communication

With

go

key After the word, concurrent programming is much simpler. At the same time, it brings new problems. If there are 2 coroutines executing concurrently, and another coroutine needs to rely on the execution results of these two coroutines, how to solve this problem? The answer is to use a channel (

Channel

). You can create a channel by using new chan in the Swoole4 coroutine. A channel can be understood as a queue with its own coroutine scheduling. It has two interfaces push and pop:

    push
  • : writes content to the channel, if it is full, it It will enter the waiting state and automatically recover when there is space
  • pop
  • : Read the content from the channel. If it is empty, it will enter the waiting state and automatically recover when there is data
  • Using channels can easily achieve
Concurrency management

.

$chan = new chan(2);

# 协程1
go (function () use ($chan) {
    $result = [];
    for ($i = 0; $i pop();
    }
    var_dump($result);
});

# 协程2
go(function () use ($chan) {
   $cli = new Swoole\Coroutine\Http\Client('www.qq.com', 80);
       $cli->set(['timeout' => 10]);
       $cli->setHeaders([
       'Host' => "www.qq.com",
       "User-Agent" => 'Chrome/49.0.2587.3',
       'Accept' => 'text/html,application/xhtml+xml,application/xml',
       'Accept-Encoding' => 'gzip',
   ]);
   $ret = $cli->get('/');
   // $cli->body 响应内容过大,这里用 Http 状态码作为测试
   $chan->push(['www.qq.com' => $cli->statusCode]);
});

# 协程3
go(function () use ($chan) {
   $cli = new Swoole\Coroutine\Http\Client('www.163.com', 80);
   $cli->set(['timeout' => 10]);
   $cli->setHeaders([
       'Host' => "www.163.com",
       "User-Agent" => 'Chrome/49.0.2587.3',
       'Accept' => 'text/html,application/xhtml+xml,application/xml',
       'Accept-Encoding' => 'gzip',
   ]);
   $ret = $cli->get('/');
   // $cli->body 响应内容过大,这里用 Http 状态码作为测试
   $chan->push(['www.163.com' => $cli->statusCode]);
});
Execution results:

htf@LAPTOP-0K15EFQI:~/swoole-src/examples/5.0$ time php co2.php
array(2) {
  ["www.qq.com"]=>
  int(302)
  ["www.163.com"]=>
  int(200)
}

real    0m0.268s
user    0m0.016s
sys     0m0.109s
htf@LAPTOP-0K15EFQI:~/swoole-src/examples/5.0$

go

is used here to create 3 coroutines, coroutines 2 and coroutines Cheng 3 requests the homepages of qq.com and 163.com respectively. Coroutine 1 needs to get the result of Http request. chan is used here to achieve concurrency management.

Coroutine
    1
  • Loop twice to pop the channel, because the queue is empty, it will enter the waiting stateCoroutine
  • 2
  • After the execution of the coroutine 3 is completed, the data will push. The coroutine 1 gets the result and continues to execute
  • Delayed tasks

In coroutine programming, you may need to automatically execute some tasks and clean up when the coroutine exits. Similar to

register_shutdown_function

of PHP, it can be implemented using defer in Swoole4. <pre class="brush:php;toolbar:false">Swoole\Runtime::enableCoroutine(); go(function () {     echo &quot;a&quot;;     defer(function () {         echo &quot;~a&quot;;     });     echo &quot;b&quot;;     defer(function () {         echo &quot;~b&quot;;     });     sleep(1);     echo &quot;c&quot;; });</pre>Execution results:

htf@LAPTOP-0K15EFQI:~/swoole-src/examples/5.0$ time php defer.php
abc~b~a
real    0m1.068s
user    0m0.016s
sys     0m0.047s
htf@LAPTOP-0K15EFQI:~/swoole-src/examples/5.0$

Conclusion

Swoole4

The Go Chan Defer provided isPHP It brings a new CSP concurrent programming model. Flexible use of various features provided by Swoole4 can solve the design and development of various complex functions at work.

The above is the detailed content of Detailed explanation of PHP coroutines: Go + Chan + Defer. For more information, please follow other related articles on the PHP Chinese website!

Statement
This article is reproduced at:segmentfault. If there is any infringement, please contact admin@php.cn delete
PHP: An Introduction to the Server-Side Scripting LanguagePHP: An Introduction to the Server-Side Scripting LanguageApr 16, 2025 am 12:18 AM

PHP is a server-side scripting language used for dynamic web development and server-side applications. 1.PHP is an interpreted language that does not require compilation and is suitable for rapid development. 2. PHP code is embedded in HTML, making it easy to develop web pages. 3. PHP processes server-side logic, generates HTML output, and supports user interaction and data processing. 4. PHP can interact with the database, process form submission, and execute server-side tasks.

PHP and the Web: Exploring its Long-Term ImpactPHP and the Web: Exploring its Long-Term ImpactApr 16, 2025 am 12:17 AM

PHP has shaped the network over the past few decades and will continue to play an important role in web development. 1) PHP originated in 1994 and has become the first choice for developers due to its ease of use and seamless integration with MySQL. 2) Its core functions include generating dynamic content and integrating with the database, allowing the website to be updated in real time and displayed in personalized manner. 3) The wide application and ecosystem of PHP have driven its long-term impact, but it also faces version updates and security challenges. 4) Performance improvements in recent years, such as the release of PHP7, enable it to compete with modern languages. 5) In the future, PHP needs to deal with new challenges such as containerization and microservices, but its flexibility and active community make it adaptable.

Why Use PHP? Advantages and Benefits ExplainedWhy Use PHP? Advantages and Benefits ExplainedApr 16, 2025 am 12:16 AM

The core benefits of PHP include ease of learning, strong web development support, rich libraries and frameworks, high performance and scalability, cross-platform compatibility, and cost-effectiveness. 1) Easy to learn and use, suitable for beginners; 2) Good integration with web servers and supports multiple databases; 3) Have powerful frameworks such as Laravel; 4) High performance can be achieved through optimization; 5) Support multiple operating systems; 6) Open source to reduce development costs.

Debunking the Myths: Is PHP Really a Dead Language?Debunking the Myths: Is PHP Really a Dead Language?Apr 16, 2025 am 12:15 AM

PHP is not dead. 1) The PHP community actively solves performance and security issues, and PHP7.x improves performance. 2) PHP is suitable for modern web development and is widely used in large websites. 3) PHP is easy to learn and the server performs well, but the type system is not as strict as static languages. 4) PHP is still important in the fields of content management and e-commerce, and the ecosystem continues to evolve. 5) Optimize performance through OPcache and APC, and use OOP and design patterns to improve code quality.

The PHP vs. Python Debate: Which is Better?The PHP vs. Python Debate: Which is Better?Apr 16, 2025 am 12:03 AM

PHP and Python have their own advantages and disadvantages, and the choice depends on the project requirements. 1) PHP is suitable for web development, easy to learn, rich community resources, but the syntax is not modern enough, and performance and security need to be paid attention to. 2) Python is suitable for data science and machine learning, with concise syntax and easy to learn, but there are bottlenecks in execution speed and memory management.

PHP's Purpose: Building Dynamic WebsitesPHP's Purpose: Building Dynamic WebsitesApr 15, 2025 am 12:18 AM

PHP is used to build dynamic websites, and its core functions include: 1. Generate dynamic content and generate web pages in real time by connecting with the database; 2. Process user interaction and form submissions, verify inputs and respond to operations; 3. Manage sessions and user authentication to provide a personalized experience; 4. Optimize performance and follow best practices to improve website efficiency and security.

PHP: Handling Databases and Server-Side LogicPHP: Handling Databases and Server-Side LogicApr 15, 2025 am 12:15 AM

PHP uses MySQLi and PDO extensions to interact in database operations and server-side logic processing, and processes server-side logic through functions such as session management. 1) Use MySQLi or PDO to connect to the database and execute SQL queries. 2) Handle HTTP requests and user status through session management and other functions. 3) Use transactions to ensure the atomicity of database operations. 4) Prevent SQL injection, use exception handling and closing connections for debugging. 5) Optimize performance through indexing and cache, write highly readable code and perform error handling.

How do you prevent SQL Injection in PHP? (Prepared statements, PDO)How do you prevent SQL Injection in PHP? (Prepared statements, PDO)Apr 15, 2025 am 12:15 AM

Using preprocessing statements and PDO in PHP can effectively prevent SQL injection attacks. 1) Use PDO to connect to the database and set the error mode. 2) Create preprocessing statements through the prepare method and pass data using placeholders and execute methods. 3) Process query results and ensure the security and performance of the code.

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

AI Hentai Generator

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
4 weeks agoBy尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. Best Graphic Settings
4 weeks agoBy尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. How to Fix Audio if You Can't Hear Anyone
4 weeks agoBy尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. Chat Commands and How to Use Them
4 weeks agoBy尊渡假赌尊渡假赌尊渡假赌

Hot Tools

SAP NetWeaver Server Adapter for Eclipse

SAP NetWeaver Server Adapter for Eclipse

Integrate Eclipse with SAP NetWeaver application server.

mPDF

mPDF

mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

Dreamweaver Mac version

Dreamweaver Mac version

Visual web development tools

ZendStudio 13.5.1 Mac

ZendStudio 13.5.1 Mac

Powerful PHP integrated development environment

MinGW - Minimalist GNU for Windows

MinGW - Minimalist GNU for Windows

This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.