# pm2
**Repository Path**: mirrors_watson/pm2
## Basic Information
- **Project Name**: pm2
- **Description**: Node.js Production Process Manager with a built-in Load Balancer.
- **Primary Language**: Unknown
- **License**: AGPL-3.0
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No
## Statistics
- **Stars**: 0
- **Forks**: 0
- **Created**: 2020-09-26
- **Last Updated**: 2026-04-12
## Categories & Tags
**Categories**: Uncategorized
**Tags**: None
## README
PM2 is a Production Runtime and Process Manager for Node.js applications with a built-in Load Balancer.
It allows you to keep applications alive forever, to reload them without downtime and facilitate common Devops tasks.
Starting an application in production mode is as easy as:
```bash
$ pm2 start app.js
```
PM2 is constantly assailed by [more than 1800 tests](https://travis-ci.org/Unitech/pm2).
Official website: [https://pm2.io/doc/](https://pm2.io/doc/)
Works on Linux (stable) & macOS (stable) & Windows (stable).
All Node.js versions are supported starting Node.js 4.X.
[](https://nodei.co/npm/pm2/)
### Installing PM2
```bash
$ npm install pm2 -g
```
*npm is a builtin CLI when you install Node.js - [Installing Node.js with NVM](https://keymetrics.io/2015/02/03/installing-node-js-and-io-js-with-nvm/)*
### Start an application
You can start any application (Node.js, Python, Ruby, binaries in $PATH...) like that:
```bash
$ pm2 start app.js
```
Your app is now daemonized, monitored and kept alive forever.
[More about Process Management](https://pm2.io/doc/en/runtime/guide/process-management/?utm_source=github)
### Container Support
With the drop-in replacement command for `node`, called `pm2-runtime`, run your Node.js application in a hardened production environment.
Using it is seamless:
```
RUN npm install pm2 -g
CMD [ "pm2-runtime", "npm", "--", "start" ]
```
[Read More about the dedicated integration](https://pm2.io/doc/en/runtime/integration/docker/?utm_source=github)
### Managing Applications
Once applications are started you can manage them easily:
To list all running applications:
```bash
$ pm2 list
```
Managing apps is straightforward:
```bash
$ pm2 stop
$ pm2 restart
$ pm2 delete
```
To have more details on a specific application:
```bash
$ pm2 describe
```
To monitor logs, custom metrics, application information:
```bash
$ pm2 monit
```
[More about Application Management](https://pm2.io/doc/en/runtime/guide/process-management/?utm_source=github)
### Cluster Mode: Node.js Load Balancing & Zero Downtime Reload
The Cluster mode is a special mode when starting a Node.js application, it starts multiple processes and load-balance HTTP/TCP/UDP queries between them. This increase overall performance (by a factor of x10 on 16 cores machines) and reliability (faster socket re-balancing in case of unhandled errors).
Starting a Node.js application in cluster mode that will leverage all CPUs available:
```bash
$ pm2 start api.js -i
```
`` can be `'max'`, `-1` (all cpu minus 1) or a specified number of instances to start.
**Zero Downtime Reload**
Hot Reload allows to update an application without any downtime:
```bash
$ pm2 reload all
```
Seamlessly supported by all major Node.js frameworks and any Node.js applications without any code change:
[More informations about how PM2 make clustering easy](https://keymetrics.io/2015/03/26/pm2-clustering-made-easy/)
### Terminal Based Monitoring
Monitor all processes launched straight from the command line:
```bash
$ pm2 monit
```
### Log Management
To consult logs just type the command:
```bash
$ pm2 logs
```
Standard, Raw, JSON and formated output are available.
Examples:
```bash
$ pm2 logs APP-NAME # Display APP-NAME logs
$ pm2 logs --json # JSON output
$ pm2 logs --format # Formated output
$ pm2 flush # Flush all logs
$ pm2 reloadLogs # Reload all logs
```
[More about log management](https://pm2.io/doc/en/runtime/guide/log-management/?utm_source=github)
### Startup Hooks Generation
PM2 can generates and configure a Startup Script to keep PM2 and your processes alive at every server restart.
Init Systems Supported: **systemd**, **upstart**, **launchd**, **rc.d**
```bash
# Generate Startup Script
$ pm2 startup
# Freeze your process list across server restart
$ pm2 save
# Remove Startup Script
$ pm2 unstartup
```
[More about Startup Hooks](https://pm2.io/doc/en/runtime/guide/startup-hook/?utm_source=github)
### Updating PM2
```bash
# Install latest PM2 version
$ npm install pm2@latest -g
# Save process list, exit old PM2 & restore all processes
$ pm2 update
```
*PM2 updates are seamless*
## Ready to Scale? Go further with PM2 Plus!
PM2
Plus Edition
```bash
$ pm2 plus
```
Once you scale you need to make sure that your application is running properly, without bugs, performance issues and without downtimes.
That's why we created PM2 Plus. It's a set of advanced features for both hardening the PM2 Runtime and monitoring applications in production.
With PM2 Plus you get:
- A Real-time Monitoring Web Interface
- Smart Exception Reporting
- Production Profiling for Memory and CPU
- PM2 Runtime High Availability Fallback
And much more like realtime logs, custom metrics, remote actions...
You can also create account via the app: [here](https://app.pm2.io/)
### PM2 Plus Features
**Visual Memory Snapshots**:
**CPU FlameGraphs**:
**Multi Server Overview**:
### PM2 Plus: Expose Custom Metrics
To get more insights on how your application behave, plug custom metrics inside your code and monitor them with the `pm2 monit` command:
In your project install [pm2-io-pm](https://github.com/keymetrics/pm2-io-apm):
```bash
$ npm install @pm2/io --save
```
Then plug a custom metric:
```javascript
const io = require('@pm2/io');
let counter = 1;
const latency = io.metric({
name : 'Counter',
value : function() {
return counter;
}
});
setInterval(() => {
counter++;
}, 1000);
```
### PM2 Plus: Module system
PM2 embeds a simple and powerful module system. Installing a module is straightforward:
```bash
$ pm2 install
```
Here are some PM2 compatible modules (standalone Node.js applications managed by PM2):
[**pm2-logrotate**](https://www.npmjs.com/package/pm2-logrotate) automatically rotate logs and limit logs size
[**pm2-server-monit**](https://www.npmjs.com/package/pm2-server-monit) monitor the current server with more than 20+ metrics and 8 actions
## CHANGELOG
[CHANGELOG](https://github.com/Unitech/PM2/blob/master/CHANGELOG.md)
## Contributors
[Contributors](http://pm2.keymetrics.io/hall-of-fame/)
## License
PM2 is made available under the terms of the GNU Affero General Public License 3.0 (AGPL 3.0).
For other licenses [contact us](mailto:contact@keymetrics.io).
[](https://github.com/igrigorik/ga-beacon)
