config.logger = Logger.new(config.log_path, 3, 10 * 1024**2)
Logfiles can get 10mb big, than they will be renamed to e.g. production.log.0 and if there are more than 3 of them they get deleted.
Maximum filesystem usage: 30mb
An alternative is using logrotate which is a harder to setup and maintain, but offers more options.