Pay-per-invocation billing model

Another significant change with the invention of serverless platforms is the pay-per-invocation model. Before this, billing models were typically per minute or hour. While this was the backbone of elastic computing, servers needed to stay up and running if they were used in any production environment.

Paying for a VPS only while it's running is a great model when developing since you can just start it at the beginning of the d``

ay and terminate it at the end of the day. However, when a system needs to be available all the time, the price you pay is nearly the same whether its CPU is at 100% usage or 0.0001% usage.

Serverless platforms, on the other hand, the bill only while the code is being executed. They are designed and shine for systems that are stateless and have a finite, relatively short duration. As such, billing is typically calculated based on a total invocation time. This model works exceptionally well for smaller systems that may get only a few calls or invocations per day. On many platforms, it's possible to run a production system that is always available completely for free. There is no such thing as idle time in the world of serverless.