[fndrplayer13]

Lambda is great though at handling services that see unpredictable spikes of traffic throughout the day where its difficult to provision quickly. Its also really good at reducing machine-management issues where your software doesn't utilize resources very well on a given machine. While its a bandaid on writing well-designed scalable software, it does allow you in the interim to take somewhat inflexible software and scale parts of it independently of physical machines.

edit: To clarify, I mean if you're running software that does something on a given set of physical machines and you cant get job throughput higher than some number, n, on a given machine it can be prohibitively expensive to scale machines ahead of time or during load. With Lambda we have the option to run a ton of independent processes on theoretically independent machines to vastly increase throughput while we slog through improving our design to improve per-machine throughput on our legacy EC2 infrastructure. Lambda allows you to isolate your scale problem to 1 job per container at a time instead of looking at machines as capable of only `n` jobs at a time.