Worker Processes initiates background scheduler everytime.

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Example Code

@router.on_event('startup')
    def schedule_job():
         """
         logger.info('*********Execute********')
         scheduler = BackgroundScheduler()
         logger.info('*********job1 fn called********')
         scheduler.add_job(job1, trigger='cron', minute=os.getenv('SYNC_DB'))
         logger.info('*********job2 fn called********')
         scheduler.add_job(job2, trigger='cron',minute=os.getenv('SCHEDULE_POPULATE_EXTERNAL_DB'))
         logger.info('*********job3 fn called********')
         scheduler.add_job(job3 ,CronTrigger.from_crontab(os.getenv('NOTIFICATION_SCHEDULE_TIME')), 
             max_instances=1)
         scheduler.start()

Description

This is my on startup event, and I have 3 background processes.

The command I am using to run my FastAPI app is ->
gunicorn -w 4 -k uvicorn.workers.UvicornWorker app.main:app --preload --timeout 30000

So, due to 4 workers, the jobs are getting called 4 times. How to avoid this?

I have tried having 3 individual startup functions, that is also not working, one of the job is to send mails periodically, so it sends same mail 4 times to a user

Operating System

Windows

Operating System Details

No response

FastAPI Version

0.89.1

Pydantic Version

1.10.6

Python Version

3.11.4

Additional Context

No response

[jgould22]

Often this type of functionality is abstracted outside of the application using something like celery.

You may be able to achieve something similar by moving this functionality into Gunicorns start up hook https://docs.gunicorn.org/en/stable/settings.html#server-hooks