45. EC2 Instance Purhcasing Options

On-Demand Instances

short workload, predictable pricing, pay by second

Reserved

(1 & 3 years)

• Reserved Instances – long workloads

• Convertible Reserved Instances – long workloads with flexible instances

Savings Plans

(1 & 3 years) –commitment to an amount of usage, long workload

Spot Instances

short workloads, cheap, can lose instances (less reliable)

Dedicated Hosts

book an entire physical server, control instance placement

Dedicated Instances

no other customers will share your hardware

Capacity Reservations

reserve capacity in a specific AZ for any duration

EC2 On Demand

• Pay for what you use:

• Linux or Windows - billing per second, after the first minute

• All other operating systems - billing per hour

• Has the highest cost but no upfront payment

• No long-term commitment

• Recommended for short-term and un-interrupted workloads, where you can't predict how the application will behave

EC2 Reserved Instances

• Up to 72% discount compared to On-demand

• You reserve a specific instance attributes (Instance Type, Region, Tenancy, OS)

• Reservation Period – 1 year (+discount) or 3 years (+++discount)

• Payment Options – No Upfront (+), Partial Upfront (++), All Upfront (+++)

• Reserved Instance’s Scope – Regional or Zonal (reserve capacity in an AZ)

• Recommended for steady-state usage applications (think database)

• You can buy and sell in the Reserved Instance Marketplace

Convertible Reserved Instance

• Can change the EC2 instance type, instance family, OS, scope and tenancy

• Up to 66% discount

EC2 Savings Plans

• Get a discount based on long-term usage (up to 72% - same as RIs)

• Commit to a certain type of usage ($10/hour for 1 or 3 years)

• Usage beyond EC2 Savings Plans is billed at the On-Demand price

• Locked to a specific instance family & AWS region (e.g., M5 in us-east-1)

• Flexible across:

• Instance Size (e.g., m5.xlarge, m5.2xlarge)

• OS (e.g., Linux, Windows)

• Tenancy (Host, Dedicated, Default)

EC2 Spot Instances

• Can get a discount of up to 90% compared to On-demand

• Instances that you can “lose” at any point of time if your max price is less than the current spot price

• The MOST cost-efficient instances in AWS

• Useful for workloads that are resilient to failure

• Batch jobs

• Data analysis

• Image processing

• Any distributed workloads

• Workloads with a flexible start and end time

• Not suitable for critical jobs or databases

EC2 Dedicated Hosts

• A physical server with EC2 instance capacity fully dedicated to your use

• Allows you address compliance requirements and use your existing serverbound

software licenses (per-socket, per-core, pe—VM software licenses)

• Purchasing Options:

• On-demand – pay per second for active Dedicated Host

• Reserved - 1 or 3 years (No Upfront, Partial Upfront, All Upfront)

• The most expensive option

• Useful for software that have complicated licensing model (BYOL – Bring Your Own License)

• Or for companies that have strong regulatory or compliance needs

EC2 Dedicated Instances

• Instances run on hardware that’s dedicated to you

• May share hardware with other instances in same account

• No control over instance placement (can move hardware after Stop / Start)

EC2 Capacity Reservations

• Reserve On-Demand instances capacity in a specific AZ for any duration

• You always have access to EC2 capacity when you need it

• No time commitment (create/cancel anytime), no billing discounts

• Combine with Regional Reserved Instances and Savings Plans to benefit from billing discounts

• You’re charged at On-Demand rate whether you run instances or not

• Suitable for short-term, uninterrupted workloads that needs to be in a specific AZ