enforce a minimum drain rate

services/real-time/app/coffee/DrainManager.coffee

@@ -4,7 +4,7 @@ module.exports = DrainManager =
 
 	startDrainTimeWindow: (io, minsToDrain)->
 		drainPerMin = io.sockets.clients().length / minsToDrain
-		DrainManager.startDrain(io, drainPerMin / 60)
+		DrainManager.startDrain(io, Math.max(drainPerMin / 60, 4)) # enforce minimum drain rate
 
 	startDrain: (io, rate) ->
 		# Clear out any old interval