Forever is a simple CLI tool for ensuring that a given script runs continuously. It is commonly used to keep Node.js applications running indefinitely by automatically restarting them in case of crashes or unexpected shutdowns. Forever provides features like logging, monitoring, and process management to help maintain the uptime of applications.
PM2 is a production process manager for Node.js applications that helps manage and keep applications online. It provides features like process monitoring, automatic restart, clustering, and log management, making it easier to deploy and maintain Node.js applications in production environments. PM2 also offers a built-in load balancer to distribute incoming traffic across multiple instances of the application.
PM2 is more popular and widely adopted compared to Forever. It has a larger user base, more community support, and is often recommended as a production process manager.
Features
PM2 offers a wide range of features including cluster mode, load balancing, automatic application restart, monitoring, log management, and more. Forever, on the other hand, focuses primarily on process management and restarting crashed applications.
Configuration
PM2 provides a comprehensive configuration file (JSON or ecosystem.config.js) where you can define your application settings, environments, and behavior. Forever, while simpler, requires you to manually specify the script to run and any additional flags or arguments.
Monitoring and Logs
PM2 includes a built-in monitoring dashboard and log management capabilities, allowing you to monitor your application's health, CPU and memory usage, and view logs in real-time. Forever does not provide these features and requires additional setup for log management and process monitoring.
Ecosystem Integration
PM2 has better integration with common ecosystem tools like Docker, systemd, and init system scripts. It provides built-in support for environment variables and can be easily integrated into deployment workflows. Forever, while still compatible with these tools, may require extra steps for seamless integration.
Community Support and Maintenance
PM2 has a larger and more active community, which translates to better community support, frequent updates, bug fixes, and security patches. Forever is still actively maintained but may have a slower release cycle and fewer community resources.
