Introduction

More and more cloud providers offer serverless services that you can use to build applications. In general, they allow you to implement functionality without having to worry about hardware, but what does that exacly mean?

Criteria

• Fully managed
  Services are managed by the cloud provider. There is no need to allocate, configure, manage hardware. There is no need to install, configure, patch software.
• Scalable
  Services automatically scale with usage and size of data stored. There is no need to add more hardware to deal with an increased demand or as you store more data, the service does that for you.
• Pay per use billing
  You only pay for resources that you use. Also called pay as you go billing model. This implies that cost should go down to zero when service is not used.

Examples

Simple Queue Service (SQS) is an example of serverless.

• ✓ It is fully managed by AWS.
• ✓ It scales with number of messages with a nearly unlimited throughput (for standard queues).
• ✓ It costs per message in queue.

On the other hand, Aurora Serverless is not a serverless service.

• ✓ It is fully managed by AWS.
• ✓ It scales with traffic and size of the data stored.
• ✗ However, there is a minimum cost of running the service (minimum 0.5 to 2 ACUs).