supervisor

UNIX-based process monitoring & control

* the following experience was with CentOS 7.3 and Supervisor 3.4

Mayeenul Islam
UX Designer & PHP Developer
mayeenulislam@github.io

Onboarding

↘️
If your application has Laravel Jobs using Queue

Why Supervisor

↘️
Any other task you need to run and control simultaneously

Because Laravel wants
us to use Supervisor

Why Supervisor

In production, you need a way to keep your queue:work processes running. A queue:work process may stop running for a variety of reasons, such as an exceeded worker timeout or the execution of the queue:restart command.

〞

There is one main advantage of the Supervisor that the task you set there is working constantly. ...when the process will finish the new one will starts immediately. Crontab runs every process for a minute minimum!

So if you have a task like queue:work is much better to use Supervisor over Crontab.

– Conrad Anker

Source: https://stackoverflow.com/q/39422942/1743124

supervisord vs. crontab

yum install epel-release -y


yum install supervisor -y

Installation

vim /etc/supervisord.conf

Configuration: Global

At the very last line change *.ini into *.conf:

[include] files = supervisord.d/*.conf
cd /etc/supervisord.d/

Configuration: Worker

Create laravel-worker.conf and edit with the following content:

[program:laravel-worker]
process_name=%(program_name)s_%(process_num)02d
command=php /var/www/html/myproject/artisan queue:work --daemon --sleep=3 --tries=3
autostart=true
autorestart=true
numprocs=8
user=apache
redirect_stderr=true
stderr_logfile=/var/www/html/myproject/storage/logs/supervisord-error.log
stdout_logfile=/var/www/html/myproject/storage/logs/supervisord.log

Configuration: Worker

laravel-worker.conf
[program:laravel-worker]
process_name=%(program_name)s_%(process_num)02d
command=php /var/www/html/myproject/artisan queue:work --daemon --sleep=3 --tries=3
autostart=true
autorestart=true
numprocs=8
user=apache
redirect_stderr=true
stderr_logfile=/var/www/html/myproject/storage/logs/supervisord-error.log
stdout_logfile=/var/www/html/myproject/storage/logs/supervisord.log

Worker name
(cannot contain space or special char)

Your command

Number of Concurrent Processes per command

Appropriate user

Log location

systemctl start supervisord

systemctl enable supervisord

systemctl status supervisord

Starting

Status

here, two workers are running, each with numprocs=8

systemctl stop supervisord supervisorctl status
supervisorctl reread
supervisorctl update
sudo supervisorctl restart all

Necessary Commands

Meaningful Logs

.env Changes don’t have an impact after changes
Stop supervisor, and start again with php artisan config:clear

Known Issues

Queue Jobs don’t have access to Session

This particular one is actually related to Events, not to the Supervisor. So don’t read any listener data from Session. Language and active user data won’t be available if read from the session

APP_URL = localhost
Supervisor reads APP_URL from the .env. So make sure the site's absolute root URL is mentioned there

systemctl stop supervisord
yum remove supervisor

rm –rf /etc/supervisord.d/

Uninstallation

Resources

Let's Supervise