EC2 Instance Families
Every EC2 instance family begins with a distinctive letter that highlights its primary use case. Below is a summary of the major instance families:| Instance Family | Use Case | Examples |
|---|---|---|
| General Purpose | Balanced CPU, memory, and networking | T2, T3, M5 |
| Compute Optimized | High-performance processors | C5, C6 |
| Memory Optimized | In-memory databases and analytics | R5, X1 |
| Accelerated Computing | GPUs, FPGAs for ML, graphics, and compute | P4, G4, F1 |
| Storage Optimized | High-throughput local storage (I/O) | I3, D3 |
| HPC Optimized | Low-latency, high-throughput networking | HPC6 |
Evaluate your application’s resource requirements—CPU, RAM, disk I/O, and network bandwidth—to identify the optimal instance family.
Key Benefits of Right-Sized Instances
Choosing the right EC2 instance type delivers:- Performance Optimization
Match vCPU, memory, storage, and networking to workload demands for minimal latency and maximum throughput. - Cost Efficiency
Right-size your instances to avoid overprovisioning and reduce AWS charges. - Specialized Workloads
Utilize GPUs, FPGAs, or large RAM pools for AI/ML training, real-time analytics, or high-performance databases. - Scalability & Flexibility
Resize or switch instance types seamlessly as demand fluctuates. - Architectural Alignment
Leverage enhanced networking (ENA), EBS-optimized instances, and Nitro system features where needed.
Instance Sizes and Scaling
Within each family, instance sizes typically double CPU and memory resources at each tier. For example, a “medium” instance might offer 1 vCPU and 4 GiB of RAM, scaling up as shown:| Size | vCPUs | Memory |
|---|---|---|
| medium | 1 | 4 GiB |
| large | 2 | 8 GiB |
| xlarge | 4 | 16 GiB |
| 2xlarge | 8 | 32 GiB |
| 4xlarge | 16 | 64 GiB |
| 8xlarge | 32 | 128 GiB |
| 12xlarge | 48 | 192 GiB |
| 16xlarge | 64 | 256 GiB |
Always consult the AWS EC2 Instance Types documentation before provisioning, as configurations and pricing change frequently.