We are running Celery behind Supervisor and start it with
celeryd --events --loglevel=INFO --concurrency=2
This, however, creates a process graph that is up to three layers deep and contains up to 7 celeryd processes (Supervisor spawns one celeryd, which spawns several others, which again spawn processes). Our machine has two CPU cores.
Are all of these processes working on tasks? Are maybe some of them just worker pools? How is the --concurrency setting connected to the number of processes actually spawned?