PM2 is a daemon process manager that will help you manage and keep your application online.

1、安裝 node 環境

cd /usr/local/
wget https://nodejs.org/dist/v12.18.3/node-v12.18.3-linux-x64.tar.xz
unxz -kv node-v12.18.3-linux-x64.tar.xz
tar xvf node-v12.18.3-linux-x64.tar
mv node-v12.18.3-linux-x64 node
echo 'export PATH=/usr/local/node/bin:$PATH' > /etc/profile.d/node.sh
source /etc/profile.d/node.sh

2、安裝 pm2

npm install pm2 -g
yarn global add pm2

3、查看用法

pm2 examples

4、命令行補全

pm2 completion install

5、常用命令

pm2 start app.js --name app_name
pm2 ls
pm2 stop app_name
pm2 restart app_name
pm2 delete app_name

Instead of app_name you can pass:

• all to act on all processes
• id to act on a specific process id

Ensure pm2 daemon has been launched

ping pm2 daemon - if not up it will launch it.

pm2 ping

kill the current pm2

pm2 kill

brings back previously saved processes via pm2 save

pm2 resurrect

Start maximum processes with LB depending on available CPUs

pm2 start app.js -i 0
pm2 start app.js -i max

Scales app up by 3 workers

pm2 scale app +3

Scales app up or down to 2 workers total

pm2 scale app 2

內存限制

pm2 start api.js --max-memory-restart 300M

6、開機自啟動

pm2 startup
pm2 unstartup

保存狀態用于自啟動或恢復

pm2 save

7、升級

npm install pm2@latest -g
pm2 update

8、查看日志

pm2 logs
pm2 logs --lines 200

9、終端監控

pm2 monit

10、圖形UI

pm2 plus

11、使用示例

pm2 start "java -jar cmp-registry.jar" --name cmp-registry # 啟動一個服務并指定服務名稱
pm2 ls # 查看服務狀態
pm2 startup # 開啟自啟動
pm2 save # 保存狀態

參考：

• https://github.com/Unitech/pm2
• https://pm2.keymetrics.io/docs/usage/pm2-doc-single-page/
• https://pm2.keymetrics.io/docs/usage/memory-limit/
• https://pm2.keymetrics.io/docs/usage/docker-pm2-nodejs/
• https://www.npmjs.com/package/nodemon
• http://www.ruanyifeng.com/blog/2016/02/linux-daemon.html