Cloud pricing: The hidden costs

“Wow! This PaaS service is a free offering from the cloud provider!!”, exclaimed an enthusiast in our team and proposed that we design the solution to maximize the use of the free PaaS service. Our director didn’t seem impressed… he said “Anything free comes with some caveats or the other. We should know the exact caveats or reasons why it’s being given as free before jumping to a design utilizing the offering”.With the experience of several cloud-native or migrated applications on the cloud, I can vouch for what the director said. The freebies on the cloud are given out for reasons such as the following, although they are not explicitly mentioned in the documentation–

• To promote a particular technology over other existing popular ones which is a go-to choice for most designers and architects.
• Startups are given free credits which would help them build solutions native to the cloud provider, in turn, they will be paid customers after the credits are consumed.
• A new service is rolled out by the cloud provider which they want to be live-tested for numerous customer scenarios

Sometimes, service is free but the caveat is that it cannot be used as a standalone service – it needs companion services that are not free. Take a look at these examples –

• A web/API service is free to use but it needs a database that is not free
• A static IP is free only until your VM which has it assigned is up and running. When the VM is shut down, you pay charges for holding the IP.
• A CI/CD pipeline service is free but the infrastructure where it deploys is obviously not free.

Yet another caveat is that a service offering may seem to have negligible charges but…Well, the devil is in the details…

• The storage is extremely cheap but you are charged for the ‘transactions’ on the storage, and each transaction size is fixed by the cloud provider. So if you perform a big insert or even read from the storage, it will be treated as multiple ‘transactions’ for billing purposes!
• The compute is offered at a very low cost but the CPU is offered as bursts per time unit, in a shared mode. So for any compute-intensive task, you end up upgrading the computer to a higher offering.

All-in-all, cloud offerings have a lot of details that need to be examined before choosing the appropriate services. What is your experience with the billing aspects of cloud solutions?