Laravel Metronome

A drop-in replacement for Laravel's built-in scheduler using an event loop instead of Cron.

Requirements

• PHP 8.2+
• Laravel 12+
• ext-pcntl

Installation

composer require rvxlab/laravel-metronome

Usage

Replace your schedule:work invocation with:

php artisan schedule:metronome

Tick rate

The tick rate controls how often the scheduler checks for due tasks in seconds. By default, the tick rate is 1 second. You can change the tick rate by passing the --tick-rate or -t option:

# Default, suitable for most workloads
php artisan schedule:metronome --tick-rate=1

# Check twice per second, useful for high-frequency sub-minute tasks
php artisan schedule:metronome --tick-rate=0.5

# Minimum allowed value (100 times per second), rarely needed in practice
php artisan schedule:metronome --tick-rate=0.01

Lower tick rates increase the number of times the scheduler checks for due tasks, which can be helpful if your workload relies on sub-minute scheduling or if you have a large number of small tasks scheduled. It's worth keeping in mind that lowering the tick rate will increase the CPU usage slightly. In most cases the difference is negligible (< 0.1%).

Overlap Protection

Metronome makes use of Laravel's overlap protection, exactly how the built-in scheduler works.

Calls to ->withoutOverlapping() will continue to work as expected.

Long-running tasks

As with Laravel's built-in scheduler, synchronous tasks that run long will delay later ticks. For tasks expected to take more than a second or two, use ->runInBackground() to shell out a child process instead.

$schedule->command('orders:process')->everyMinute()->runInBackground();

Running with Supervisor

Add the following to your Supervisor configuration, adjusting command, user, and stdout_logfile to match your setup.

[program:laravel-metronome]
process_name = %(program_name)s_%(process_num)02d
command = php /var/www/html/artisan schedule:metronome
autostart = true
autorestart = true
stopasgroup = true
killasgroup = true
user = www-data
numprocs = 1
redirect_stderr = true
stdout_logfile = /var/www/html/storage/logs/metronome.log
stopwaitsecs = 60

numprocs must be 1. Running multiple instances will cause tasks to fire multiple times. stopwaitsecs should be set high enough to allow any currently running tasks to finish before Supervisor force-kills the process.

Running with Docker

Because Metronome doesn't rely on Cron, it's really easy to have it run in a Docker container, either directly or through Supervisor.

Without Supervisor, you can run the scheduler directly as the container's entrypoint:

FROM php:8.2-cli

RUN docker-php-ext-install pcntl

WORKDIR /var/www/html

COPY . .

CMD ["php", "artisan", "schedule:metronome"]

Or with Supervisor, if you need it running alongside other processes:

FROM php:8.2-cli

RUN apt-get update && apt-get install -y \
        supervisor \
    && rm -rf /var/lib/apt/lists/* \
    && docker-php-ext-install pcntl

WORKDIR /var/www/html

COPY . .

COPY supervisord.conf /etc/supervisor/conf.d/laravel-metronome.conf

CMD ["/usr/bin/supervisord", "-n", "-c", "/etc/supervisor/supervisord.conf"]

Stopping the Scheduler

Send SIGINT (Ctrl+C) or SIGTERM to stop the process cleanly. Laravel's shutdown logic runs before the process exits, so process managers like Supervisor and systemd work out of the box.

Known limitations

• Last-run state is held in memory and not persisted across process restarts. A task that ran shortly before a crash may re-run immediately on startup.

License

This package is licensed under MIT.