Messaging queues are a core part of a lot of high scale distributed systems (source - Twitter) You want enough queue space to handle the expected volume and the

Messaging queues are a core part of a lot of high scale distributed systems (source - Twitter) You want enough queue space to handle the expected volume and then some. Assuming you have that, you don't need to instantly scale instances out to match the amount of messages, you just need to catch up before the queue space runs out.