Redis backend too many open files

[mikelane]

Describe the problem

We have implemented django constance with a redis backend and a 60 local cache. When there is a large amount of traffic, our service becomes unstable, our latency spikes, and we get a ton of logs which say "too many open files." We have isolated the django-constance change as the only change we are deploying when we do this.

Could this issue possibly be related to this: https://stackoverflow.com/a/25283155/3858494?

Steps to reproduce

Enable django-constance with a Redis backend and a 60 second local cache. Subject the service to a heavy load.

System configuration

I don't want to reveal this in a public forum.

• Django version:
• Python version:
• Django-Constance version:

[horpto]

Hi, do you use RedisBackend or CachedRedisBackend? Do you use something like gevent ? Which version of the python redis-py lib do you use? Also you can limit number of connections with he max_connections option

[mikelane]

We used the CachingRedisBackend. We do not use gevent.

[horpto]

Well, great somebody except me uses caching. All calls to redis in CachingRedisBackend are occured under the lock so redis client should have only one connection. As constance object is singleton to all threads so something wrong maybe with redis-py client internals. What is current limit of connections of redis and how many redis clients (app node * app threads) is there?

[sergei-iurchenko]

show your code please