Introduction to PM2

PM2 is a process manager for Node.js applications. It allows developers to manage, monitor, and scale their Node.js applications with ease. With PM2, you can keep your applications running 24/7, with zero downtime and automated clustering.

Features

PM2 comes packed with a lot of useful features, including:

• Process management: Monitor and manage your applications with ease.
• Automatic restart: Upon crashes or server restarts, PM2 automatically restarts your applications.
• Load balancing: With built-in load balancing, PM2 automatically distributes the traffic among multiple instances of your application.
• Zero downtime deployment: With PM2, you can deploy new versions of your application without experiencing any downtime.
• Logs management: PM2 collects all your application logs in one place and allows you to monitor them in real-time.
• Performance monitoring: PM2 can monitor your application's CPU usage, memory usage, and other metrics to help you optimize your application's performance.
• Clustering: PM2 can automatically cluster your application and scale it up or down based on traffic demand.

Installation

To install PM2, execute the following command:

npm install pm2 -g

Usage

To start an application with PM2, simply execute the following command:

pm2 start app.js

PM2 will automatically start the application in cluster mode, with the default number of instances being the number of available CPUs.

To monitor the status of your application, use the following command:

pm2 status

PM2 will show you the status of all your running processes and their resource usage.

To stop your application, use the following command:

pm2 stop app

PM2 will stop all the processes associated with the given application.

Conclusion

PM2 is a powerful process manager for Node.js applications. With its many useful features, it can make the management and scaling of your applications a breeze. Whether you're running a small personal project or a large production environment, PM2 is worth your consideration.