Running Meridian

You have two options:

1. Keep your workers. Run php artisan queue:work database ... with Supervisor or systemd as usual: jobs, metrics and workers show up in the dashboard.
2. Let Meridian supervise them, like Horizon: run one long-lived process and Meridian starts, restarts and balances the queue:work processes of the current environment.

php artisan meridian

Command	Description
meridian	Start the master supervisor
meridian:status	Show the status, the supervisors and the workload
meridian:pause / meridian:continue	Pause or resume the workers (--all for every host)
meridian:pause-supervisor {name} / meridian:continue-supervisor {name}	Pause or resume the workers of one supervisor (--all for every host)
meridian:supervisors	List the running supervisors
meridian:supervisor-status {name}	Show the status of a supervisor
meridian:terminate	Finish the running jobs, then stop the master supervisor (--all for every host)
meridian:list	List the machines running Meridian (the master supervisors)
meridian:purge	Terminate the workers left by a master that was killed, and forget the dead processes of this machine (--signal=SIGTERM)
meridian:snapshot	Store a metrics snapshot, import the jobs pushed without event, check the wait times
meridian:prune	Delete old completed and failed jobs, metrics and stale heartbeats
meridian:doctor	Check the installation: migrations, queue tables, supervisors, scheduler, redaction and dashboard access, with how to fix each problem
meridian:forget {uuid} / meridian:forget --all	Delete a failed job, or all of them, from Meridian and from the failed jobs table
meridian:clear {connection?} --queue=	Delete the jobs waiting on a queue (asks for confirmation in production, --force to skip it)
meridian:clear-metrics	Delete every metrics snapshot
meridian:listen	Local development: run Meridian and restart it whenever a PHP file of the application changes
meridian:top	Live view of the queues, running jobs, supervisors, errors and failing scheduled tasks in the terminal (--interval=2, --once)

php artisan meridian requires the pcntl and posix extensions. When its memory exceeds memory_limit (64 MB by default, 0 to disable), it finishes the running jobs and exits with the code 12, so that your process monitor starts it again with fresh memory.

In local development, php artisan meridian:listen runs Meridian and restarts it whenever a PHP file of the directories listed in the watch option changes (app, config, routes…). Unlike horizon:listen, it needs neither Node nor any npm package: it polls the files every second (--poll= to change it).

Deploying Meridian

Keep php artisan meridian running with a process monitor such as Supervisor, and run php artisan meridian:terminate during each deployment: the running jobs finish, Meridian exits, and the process monitor restarts it with your new code.

[program:meridian]
process_name=%(program_name)s
command=php /var/www/app/artisan meridian
autostart=true
autorestart=true
user=forge
redirect_stderr=true
stdout_logfile=/var/www/app/storage/logs/meridian.log
stopwaitsecs=3600

stopwaitsecs must be longer than your longest job.

Fast termination: by default, meridian:terminate waits for the running jobs to finish before the master exits, which may delay your deployment. Like Horizon, set 'fast_termination' => true to make the master exit right away: its workers finish their current job on their own, while your process monitor already starts the new master with your new code.

If a master was killed without terminating its workers (kill -9, out of memory...), php artisan meridian:purge terminates the workers it left behind.