Missing config options for --without-mingle and --without-gossip

[patrickwolf]

Celery contains the features mingle and gossip which are turned on by default.
Based on this ticket: #2565 it looks like there is a bug with UTC which leads to an error message with the gossip feature.

When starting a worker "gossip" can be disabled from the command line but when using Celery from within Python it can't as its not an option in the config file.
Would be helpful to add these both as an option to the config.

command line options:
http://celery.readthedocs.org/en/latest/whatsnew-3.1.html#gossip-worker-worker-communication
http://celery.readthedocs.org/en/latest/whatsnew-3.1.html#mingle-worker-synchronization
config doesn't provide options:
https://celery.readthedocs.org/en/latest/configuration.html
other user asking for the same feature:
https://stackoverflow.com/questions/24783962/how-to-disable-gossip-and-mingle-components-of-celery

Thanks!

[ask]

We have stopped adding configuration options for every worker feature as we're trying to keep the list
of configuration keys small. the worker logfile, and loglevel configurations were also removed.

It's better to just configure this for deployment of the workers.

[vesnikos]

Would be good to have because of #3895

[waleedsamy]

@omarkhan @ask
CC @ashb
Can you reconsider reopening this ticket, I think it worth enable those flag through configuration.
Apache Airflow is creating celery worker programmatically and currently no way to pass such parameters to airflow worker. It feels helpless because one couldn't disable gossip/mingle with config.

I think every Apache Airflow installation out there (at least the ones with more than 200 worker) is wasting a lot of CPU time due to having gossip enabled.

[ashb]

We can add this via the celery config in Airflow I think, no celery CLI option is needed for that

[waleedsamy]

I think adding them in config file won't help (hence this ticket).

[waleedsamy]

@auvipy what do you think about #2566 (comment)?

[radiantone]

This is needed. Pretty obvious.