Why PM2 is Essential for Applications in Production?

When deploying a Node.js application in a production environment, ensuring stability, efficiency, and reliability is crucial. This is where PM2, a powerful process manager for Node.js applications, becomes an invaluable tool. PM2 simplifies process management, enhances performance, and provides robust monitoring capabilities. In this post, we’ll explore why PM2 is essential for running Node.js applications in production.

To ensure a Node.js app keeps running smoothly in production on Linux/Ubuntu, there are many ways to achieve this, but here are some of the essential steps that will help you elevate your application’s performance to the ‘next level’:

1. Regularly monitor system resource usage to prevent bottlenecks
2. Implement error handling and logging to quickly diagnose and fix issues as they arise
3. Utilize process managers like PM2 or Forever to automatically restart your application in case of failures
4. Ensure that your dependencies are always updated and secure to avoid vulnerabilities
5. A bonus step: consider employing load balancing and clustering techniques to enhance the app’s scalability and availability. Nginx is great here even if you have one instance.

1. Use a Process Manager (PM2)

PM2 is a popular process manager for Node.js applications that provides automatic restarts, logging, and monitoring.

Install PM2 globally:

npm install -g pm2

Start your application with PM2:

pm2 start app.js --name myNodeJSAppButInProd

Managing different configurations for development, testing, and production environments can be cumbersome. PM2 allows you to define environment-specific variables using an ecosystem file:

module.exports = {
  apps: [{
    name: "my-app",
    script: "app.js",
    env: {
      NODE_ENV: "development",
    },
    env_production: {
      NODE_ENV: "production",
    }
  }]
};

This ensures that your application loads the appropriate settings based on the environment, reducing configuration errors.

Ensure PM2 restarts on reboot:

pm2 startup
pm2 save