What are the methods to make Cluster share memory?
This time I will bring you the methods of making Cluster share memory, and the precautions of making Cluster share memory. The following is a practical case, let's take a look.
The standard API of Node.js does not provide process shared memory. However, through the send method of the IPC interface and monitoring of message events, a collaboration mechanism between multiple processes can be implemented to operate shared memory through communication. .
##Basic usage of IPC:
// worker进程 发送消息
process.send(‘读取共享内存');
// master进程 接收消息 -> 处理 -> 发送回信
cluster.on('online', function (worker) {
// 有worker进程建立，即开始监听message事件
worker.on(‘message', function(data) {
// 处理来自worker的请求
// 回传结果
worker.send(‘result')
});
});In Node.js, through send and on('message', The IPC communication implemented by callback) has several characteristics. First of all, master and workers can communicate with each other, but workers cannot communicate directly with each other, but workers can communicate indirectly through master forwarding. In addition, the data passed through the send method will be processed by JSON.stringify before being passed. After being received, it will be parsed using JSON.parse. Therefore, the Buffer object will become an array after being passed, but the function cannot be passed directly. On the other hand, all data types except buffer and function can be passed directly (which is already very powerful, and buffer and function can also be passed using alternative methods).
Based on the above characteristics, we can design a solution to share memory through IPC:
1. As a user of shared memory, the worker process does not directly operate the shared memory, but notifies the master process through the send method to perform write (set) or read (get) operations.
2. The master process initializes an Object object as shared memory, and reads and writes the key value of the Object according to the message sent by the worker.
3. Since cross-process communication is used, the set and get initiated by the worker are asynchronous operations. The master performs actual read and write operations according to the request, and then returns the results to the worker (that is, sending the result data to the worker).
##Data Format
In order to implement asynchronous reading and writing functions between processes, the format of communication data needs to be standardized.
The first is the worker’s request data:
requestMessage = {
isSharedMemoryMessage: true, // 表示这是一次共享内存的操作通信
method: ‘set', // or ‘get' 操作的方法
id: cluster.worker.id, // 发起操作的进程（在一些特殊场景下，用于保证master可以回信）
uuid: uuid, // 此次操作的（用于注册/调用回调函数）
key: key, // 要操作的键
value: value // 键对应的值（写入）
}After receiving the data, the master will perform corresponding operations according to the method, and then send the result data to the corresponding worker according to requestMessage.id. The data format is as follows:
responseMessage = {
isSharedMemoryMessage: true, // 标记这是一次共享内存通信
uuid: requestMessage.uuid, // 此次操作的唯一标示
value: value // 返回值。get操作为key对应的值，set操作为成功或失败
}The significance of standardizing the data format is that after receiving the request, the master can send the processing result to the corresponding worker, and after the worker receives the returned result, it can call the callback corresponding to the communication, thereby achieving collaboration.
After standardizing the data format, the next thing to do is to design two sets of codes, respectively for the master process and the worker process, to monitor communication and process communication data to realize the function of shared memory.
##User class
Instances of the User class work in the worker process and are responsible for sending requests to operate shared memory and listening for replies from the master.
var User = function() {
var self = this;
self.uuid = 0;
// 缓存回调函数
self.getCallbacks = {};
// 接收每次操作请求的回信
process.on('message', function(data) {
if (!data.isSharedMemoryMessage) return;
// 通过uuid找到相应的回调函数
var cb = self.getCallbacks[data.uuid];
if (cb && typeof cb == 'function') {
cb(data.value)
}
// 卸载回调函数
self.getCallbacks[data.uuid] = undefined;
});
};
// 处理操作
User.prototype.handle = function(method, key, value, callback) {
var self = this;
var uuid = self.uuid++;
process.send({
isSharedMemoryMessage: true,
method: method,
id: cluster.worker.id,
uuid: uuid,
key: key,
value: value
});
// 注册回调函数
self.getCallbacks[uuid] = callback;
};
User.prototype.set = function(key, value, callback) {
this.handle('set', key, value, callback);
};
User.prototype.get = function(key, callback) {
this.handle('get', key, null, callback);
};##Manager class
Instances of the Manager class work in the master process to initialize an Object as shared memory, add key-value pairs to the shared memory according to the request of the User instance, or read the key value, and then send the result back.
var Manager = function() {
var self = this;
// 初始化共享内存
self.sharedMemory = {};
// 监听并处理来自worker的请求
cluster.on('online', function(worker) {
worker.on('message', function(data) {
// isSharedMemoryMessage是操作共享内存的通信标记
if (!data.isSharedMemoryMessage) return;
self.handle(data);
});
});
};
Manager.prototype.handle = function(data) {
var self = this;
var value = this[data.method](data);
var msg = {
// 标记这是一次共享内存通信
isSharedMemoryMessage: true,
// 此次操作的唯一标示
uuid: data.uuid,
// 返回值
value: value
};
cluster.workers[data.id].send(msg);
};
// set操作返回ok表示成功
Manager.prototype.set = function(data) {
this.sharedMemory[data.key] = data.value;
return 'OK';
};
// get操作返回key对应的值
Manager.prototype.get = function(data) {
return this.sharedMemory[data.key];
};##How to use
if (cluster.isMaster) {
// 初始化Manager的实例
var sharedMemoryManager = new Manager();
// fork第一个worker
cluster.fork();
// 1秒后fork第二个worker
setTimeout(function() {
cluster.fork();
}, 1000);
} else {
// 初始化User类的实例
var sharedMemoryUser = new User();
if (cluster.worker.id == 1) {
// 第一个worker向共享内存写入一组数据，用a标记
sharedMemoryUser.set('a', [0, 1, 2, 3]);
}
if (cluster.worker.id == 2) {
// 第二个worker从共享内存读取a的值
sharedMemoryUser.get('a', function(data) {
console.log(data); // => [0, 1, 2, 3]
});
}
}The above is a multi-process shared memory function implemented through IPC communication. It should be noted that this method directly caches data in the memory of the master process. You must pay attention to the memory usage. You can consider adding it here. Some simple elimination strategies to optimize memory usage. In addition, if the data read and written in a single time is relatively large, the time consuming of IPC communication will also increase accordingly. I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!
Recommended reading:
el-uploadHow to upload an Excel fileDynamicly obtain the bytes and characters of the current input content numberThe above is the detailed content of What are the methods to make Cluster share memory?. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
How to delete WeChat friends? How to delete WeChat friends
Mar 04, 2024 am 11:10 AM
WeChat is one of the mainstream chat tools. We can meet new friends, contact old friends and maintain the friendship between friends through WeChat. Just as there is no such thing as a banquet that never ends, disagreements will inevitably occur when people get along with each other. When a person extremely affects your mood, or you find that your views are inconsistent when you get along, and you can no longer communicate, then we may need to delete WeChat friends. How to delete WeChat friends? The first step to delete WeChat friends: tap [Address Book] on the main WeChat interface; the second step: click on the friend you want to delete and enter [Details]; the third step: click [...] in the upper right corner; Step 4: Click [Delete] below; Step 5: After understanding the page prompts, click [Delete Contact]; Warm
How to write a novel in the Tomato Free Novel app. Share the tutorial on how to write a novel in Tomato Novel.
Mar 28, 2024 pm 12:50 PM
Tomato Novel is a very popular novel reading software. We often have new novels and comics to read in Tomato Novel. Every novel and comic is very interesting. Many friends also want to write novels. Earn pocket money and edit the content of the novel you want to write into text. So how do we write the novel in it? My friends don’t know, so let’s go to this site together. Let’s take some time to look at an introduction to how to write a novel. Share the Tomato novel tutorial on how to write a novel. 1. First open the Tomato free novel app on your mobile phone and click on Personal Center - Writer Center. 2. Jump to the Tomato Writer Assistant page - click on Create a new book at the end of the novel.
How to recover deleted contacts on WeChat (simple tutorial tells you how to recover deleted contacts)
May 01, 2024 pm 12:01 PM
Unfortunately, people often delete certain contacts accidentally for some reasons. WeChat is a widely used social software. To help users solve this problem, this article will introduce how to retrieve deleted contacts in a simple way. 1. Understand the WeChat contact deletion mechanism. This provides us with the possibility to retrieve deleted contacts. The contact deletion mechanism in WeChat removes them from the address book, but does not delete them completely. 2. Use WeChat’s built-in “Contact Book Recovery” function. WeChat provides “Contact Book Recovery” to save time and energy. Users can quickly retrieve previously deleted contacts through this function. 3. Enter the WeChat settings page and click the lower right corner, open the WeChat application "Me" and click the settings icon in the upper right corner to enter the settings page.
How to enter bios on Colorful motherboard? Teach you two methods
Mar 13, 2024 pm 06:01 PM
Colorful motherboards enjoy high popularity and market share in the Chinese domestic market, but some users of Colorful motherboards still don’t know how to enter the bios for settings? In response to this situation, the editor has specially brought you two methods to enter the colorful motherboard bios. Come and try it! Method 1: Use the U disk startup shortcut key to directly enter the U disk installation system. The shortcut key for the Colorful motherboard to start the U disk with one click is ESC or F11. First, use Black Shark Installation Master to create a Black Shark U disk boot disk, and then turn on the computer. When you see the startup screen, continuously press the ESC or F11 key on the keyboard to enter a window for sequential selection of startup items. Move the cursor to the place where "USB" is displayed, and then
The secret of hatching mobile dragon eggs is revealed (step by step to teach you how to successfully hatch mobile dragon eggs)
May 04, 2024 pm 06:01 PM
Mobile games have become an integral part of people's lives with the development of technology. It has attracted the attention of many players with its cute dragon egg image and interesting hatching process, and one of the games that has attracted much attention is the mobile version of Dragon Egg. To help players better cultivate and grow their own dragons in the game, this article will introduce to you how to hatch dragon eggs in the mobile version. 1. Choose the appropriate type of dragon egg. Players need to carefully choose the type of dragon egg that they like and suit themselves, based on the different types of dragon egg attributes and abilities provided in the game. 2. Upgrade the level of the incubation machine. Players need to improve the level of the incubation machine by completing tasks and collecting props. The level of the incubation machine determines the hatching speed and hatching success rate. 3. Collect the resources required for hatching. Players need to be in the game
How to set font size on mobile phone (easily adjust font size on mobile phone)
May 07, 2024 pm 03:34 PM
Setting font size has become an important personalization requirement as mobile phones become an important tool in people's daily lives. In order to meet the needs of different users, this article will introduce how to improve the mobile phone use experience and adjust the font size of the mobile phone through simple operations. Why do you need to adjust the font size of your mobile phone - Adjusting the font size can make the text clearer and easier to read - Suitable for the reading needs of users of different ages - Convenient for users with poor vision to use the font size setting function of the mobile phone system - How to enter the system settings interface - In Find and enter the "Display" option in the settings interface - find the "Font Size" option and adjust it. Adjust the font size with a third-party application - download and install an application that supports font size adjustment - open the application and enter the relevant settings interface - according to the individual
Summary of methods to obtain administrator rights in Win11
Mar 09, 2024 am 08:45 AM
A summary of how to obtain Win11 administrator rights. In the Windows 11 operating system, administrator rights are one of the very important permissions that allow users to perform various operations on the system. Sometimes, we may need to obtain administrator rights to complete some operations, such as installing software, modifying system settings, etc. The following summarizes some methods for obtaining Win11 administrator rights, I hope it can help you. 1. Use shortcut keys. In Windows 11 system, you can quickly open the command prompt through shortcut keys.
Detailed explanation of Oracle version query method
Mar 07, 2024 pm 09:21 PM
Detailed explanation of Oracle version query method Oracle is one of the most popular relational database management systems in the world. It provides rich functions and powerful performance and is widely used in enterprises. In the process of database management and development, it is very important to understand the version of the Oracle database. This article will introduce in detail how to query the version information of the Oracle database and give specific code examples. Query the database version of the SQL statement in the Oracle database by executing a simple SQL statement
