Arch Linux

Description: The default configuration of redis has a 10,000 max-connection limit. This requires the redis process to be able to create 10,032 file descriptors, higher than the default, causing a warning on startup. Setting LimitNOFILE=10032 in the systemd service fixes this.


Additional info:
* redis 3.0.1-1


Steps to reproduce:

1. Install redis.
2. Start it.
3. Inspect that in the logs, the following errors are generated:

# Current maximum open files is 4096. maxclients has been reduced to 4064 to compensate for low ulimit. If you need higher maxclients...
# Redis can't set maximum open files to 10032 because of OS error: Operation not permitted.
# You requested maxclients of 10000 requiring at least 10032 max file descriptors.

4. Add an override (systemctl edit redis.service) containing:

[Service]
LimitNOFILE=10032

5. Restart redis.
6. Observe that the log messages are gone.


I think that either we should change the Arch default redis configuration to less than 10,000 connections, or set the LimitNOFILE in the service by default. (I think the latter makes more sense and will match what users expect.)