Lambda

The new concept called “serverless” is all based on the humble function. Today there is even a term “FAAS”, or Function As A Service. Cloud providers are trying to over the endlessly available ability to invoke functions at will without limit. There is of course no infinite or endless resources. There is of course a server that the function is invoked upon. The idea is pushing the concept of container isolation one step further. No longer requiring a host to provision. Rather, use a shared host. With Lambda came the ability to make scalable application that no longer required resources pre-allocated sitting their. Lambda is provisioned at runtime, not ahead of time. That means you don’t pay for the function unless it is being used. In terms of cost this was a game changer. You could build a system that is just sitting still not costing a lot unless utilized.

There are some limitations of Lambda.

1. Execution time may not exceed 15 minutes.
2. If function is not already provisioned on server, additional warm-up time is needed.

Lambda is not the choice for every scenario, but they do fill a very large place in many company’s portfolio. Today Lambda can even use a Docker image so the options are nearly endless.