Fix shared Redis connection issue on Passenger

config/initializers/passenger_fix.rb

+if defined?(PhusionPassenger)
+
+  # When you're using Passenger with smart-lv2 (default) or smart spawn method,
+  # Resque doesn't recognize that it has been forked and should re-establish
+  # Redis connection. You can see this error message in log:
+  #   Redis::InheritedError, Tried to use a connection from a child process 
+  #   without reconnecting. You need to reconnect to Redis after forking.
+  # 
+  # This solution is based on 
+  # https://github.com/redis/redis-rb/wiki/redis-rb-on-Phusion-Passenger
+  #
+  PhusionPassenger.on_event(:starting_worker_process) do |forked|
+    # if we're in smart spawning mode, reconnect to Redis
+    Resque.redis.client.reconnect if forked
+  end
+end