Will this break with multiple Craft app instances? about craft-async-queue HOT 3 CLOSED

Sorry for the late reply.

In my experience, running multiple concurrent queue workers (craft queue/run) with Craft's database queue CAN lead to deadlocks.

I'd say, you can safely use Async Queue on multiple HTTP frontends as long as you set ASYNC_QUEUE_CONCURRENCY to 1.

First question: is this cron necessary?

Only if someone schedules a job with a delay

Second: what will happen when my app is scaled?

In theory, it does not matter how many instances you use. The "locking" does not rely on the local file system, but on the database, which means you can not use Redis.

If you expect a serious amount of queue jobs, better use a supervisored queue runner and Redis.

from craft-async-queue.

Great, thanks for the feedback! I have since changed ASYNC_QUEUE_CONCURRENCY to 1 which I think has reduced deadlocks (but not fully) and we seem to be running two app instances OK.

I do find that sometimes the queue is stuck and the only way seems to be running the Async Queue Test utility that kicks it back into processing again. I'm not sure why this happens and it's why I was thinking of running queue/run periodically via a cron. Have you encountered this before?

from craft-async-queue.

I'm not a "user", but from time to time users experience stucking queue messages.
That's probably not an issue with this plugin, but with Craft/Yii, as the plugin simply runs craft queue/run.

from craft-async-queue.