EC2 Pricing Plans

EC2 On-Demand Pricing

Billing by the hour or second, with modifiable compute capacity.

Workload Types
Short term / fluctuating
Uninterrupted run times
* Development and test environments

Least Commitment - On-Demand
Low cost/flexible
Only pay per hour
Short-term, spiky, unpredictable workloads
Cannot be interrupted
* For first time apps

EC2 Reserved Instances Pricing

Up to 72% less than on-demand pricing; instances available as-needed.
They are available as-needed because you reserved them.
- Based on "ability to commit" to using the instance
(Customer able to commit to 1-yr to 3-yr term).

Can resell unused reserved instances (when your business makes a change).

Workload Types:
Steady-state applications
Predictable usage

EC2 Spot Instances Pricing

Steep discounts, run continuously for a set duration at lower price points.

AWS has all that compute capacity (specific region, specific instance type), and
it's not all in use all the time. That's where Spot Instances come in.

Depending on certain workloads/use cases, e.g., batch processing job 1/week
Whenever AWS has UNUSED/SPARE compute capacity, I'm willing to pay this amount for that EC2 instance type.
It will sit there ready to run until AWS has an instance available that meet the instance type, price point, etc
It can handle interruptions.
Your spot instance is not guaranteed.
Once you start using it, it can be taken away from you (person is willing to pay full price for it)
- You get a 2 minute warning when this happens
- Your application should be able to pause, wait for another spot instance to become available, and then continue where it left off.
- Good for programs that can be resumed without negative impact.

The bidding process on spot instances:
There's a general "market price". You say "I'm willing to pay {x} amount for a spot instance."
As long as the "market price" stays below your bid, you'll keep it.
When the "market price" goes up, you lose that spot instance.
Up to 90% discount.

Savings Plan vs Spot Instances Plan
Savings plans: Agnostic to location. Discount for a SET level of compute usage, and it's GLOBAL.
- You commit to a usage level
- You can use savings plans beyond EC2 instances.
Spot Instances: Set to a specific instance family, in a specific AWS location.

Dedicated Hosts Pricing

Physical EC2 server fully dedicated to your use (Single Tenant Environment)

Normally, an EC2 instance would partition components of the same underlying hardware for
you to share with another user, although it's isolated - the other user will not have
access to your data.

But if you're, for instance, a government entity and need the promise of exclusive use of
hardware, you'll want a dedicated host.

When you need a guarantee of isolated hardware, dedicated hosts is the pricing model you'll follow.