EC2 vs Fargate: Choosing the Right Container Platform

When running containers on AWS, you have two primary options: managing your own EC2 instances or using AWS Fargate for serverless container execution. Each approach has distinct advantages and trade-offs that make it better suited for different scenarios.

> Key Takeaways > > - EC2 gives you full control and is 40-70% cheaper at scale with Reserved or Spot Instances > - Fargate eliminates infrastructure management overhead but costs more for steady-state workloads > - Hybrid approaches using ECS capacity providers let you optimize for both cost and flexibility > - Choose Fargate for variable workloads and small teams; choose EC2 when cost optimization and hardware control are priorities

What Are the Key Differences Between EC2 and Fargate?

Amazon EC2 gives you full control over the underlying compute instances running your containers, while AWS Fargate is a serverless container engine that removes the need to provision, configure, or scale virtual machines.

Amazon EC2 with ECS/EKS

You manage the underlying EC2 instances:

• Full control over instance types and configurations
• Direct access to the host operating system
• Responsibility for patching, scaling, and maintenance
• More complex but more flexible

AWS Fargate

Serverless container execution:

• No infrastructure to manage
• Pay per vCPU and memory used
• Automatic scaling built-in
• Simpler but with some limitations

Feature Comparison

Control and Flexibility

| Aspect | EC2 | Fargate | |--------|-----|---------| | Instance Types | Full selection | Predefined configurations | | GPU Support | Yes | Yes (limited) | | Custom AMIs | Yes | No | | Host Access | Full access | No access | | Privileged Containers | Yes | No | | Networking Modes | All modes | awsvpc only |

Operational Complexity

| Aspect | EC2 | Fargate | |--------|-----|---------| | Patching | Your responsibility | AWS managed | | Scaling | Configure ASG | Automatic | | Capacity Planning | Required | Not needed | | Security Hardening | Your responsibility | AWS managed |

According to a 2024 Datadog State of Serverless report, Fargate adoption has grown by over 30% year-over-year, with more than half of AWS container customers now using Fargate for at least some workloads (source: Datadog, 2024).

How Do EC2 and Fargate Compare on Cost?

EC2 pricing is based on instance hours regardless of container utilization, while Fargate charges only for the vCPU and memory resources allocated to each container task, making Fargate simpler to budget but EC2 more cost-effective at high utilization.

EC2 Pricing Model

Pay for instances regardless of container utilization:

Monthly Cost = Instance Hours x Instance Price
             + EBS Storage
             + Data Transfer

Advantages:

• Reserved instances for predictable workloads (up to 72% savings)
• Spot instances for fault-tolerant workloads (up to 90% savings)
• Better economics at high utilization

Fargate Pricing Model

Pay only for resources allocated to containers:

Monthly Cost = (vCPU hours x vCPU price)
             + (GB memory hours x memory price)
             + Data Transfer

Advantages:

• No charge for idle capacity
• Predictable per-task pricing
• No commitment required

Cost Comparison Example

Running 10 containers (2 vCPU, 4GB each) for a month:

Fargate:

• vCPU: 10 x 2 x 730 hours x $0.04048 = $591
• Memory: 10 x 4 x 730 hours x $0.004445 = $130
• Total: ~$721/month

EC2 (On-Demand m5.xlarge):

• 3 instances to host 10 containers
• 3 x 730 hours x $0.192 = $420
• Total: ~$420/month

EC2 (Reserved 1-year):

• 3 x 730 hours x $0.121 = $265
• Total: ~$265/month

Fargate is simpler but EC2 is more cost-effective at scale

You can further reduce EC2 costs by running containers on Graviton4 ARM-based instances, which offer an additional 20-40% savings over x86 instances.

Performance Considerations

EC2 Advantages

• Consistent Performance: Dedicated or placement groups for guaranteed resources
• Instance Store: NVMe storage for high-performance temporary data
• Networking: Enhanced networking with up to 100 Gbps
• Customization: Kernel tuning and system optimization

Fargate Advantages

• Isolation: Each task runs in its own kernel runtime
• Startup Time: Fast container startup (typically <30 seconds)
• Resource Efficiency: Exact resource allocation without waste

Use Case Recommendations

Choose EC2 When:

Cost Optimization is Critical

- High-volume, steady-state workloads - Can leverage reserved or spot instances - High container density is achievable

Specialized Hardware Required

- GPU workloads for ML/AI - High-memory instances for databases - Local NVMe storage requirements

Full Control Needed

- Custom kernel parameters - Specific security configurations - Privileged container operations - Direct host access requirements

Complex Networking

- Host networking mode - Multiple network interfaces - Specific placement requirements

Choose Fargate When:

Operational Simplicity

- Small teams without dedicated DevOps - Rapid development and deployment - Minimal infrastructure management preference

Variable Workloads

- Unpredictable traffic patterns - Batch jobs with varying schedules - Development and testing environments

Security Priority

- Strong isolation requirements - Compliance requirements - Minimal attack surface preference

Quick Start Projects

- Proof of concepts - MVPs and prototypes - New services without established patterns

For detailed guidance on Fargate container logging best practices, see our dedicated guide.

How Can You Use Both EC2 and Fargate Together?

ECS capacity providers allow you to run EC2 and Fargate compute in the same cluster, enabling cost-optimized base capacity on EC2 with automatic burst scaling to Fargate during peak demand.

Capacity Providers

Use both EC2 and Fargate in the same cluster:

# ECS Cluster with mixed capacity providers
ClusterCapacityProviders:
  - CapacityProvider: FARGATE
    Weight: 1
    Base: 0
  - CapacityProvider: EC2-Spot
    Weight: 4
    Base: 2

Benefits:

• Base capacity on EC2 for cost efficiency
• Burst to Fargate for peak demand
• Spot instances for fault-tolerant workloads

According to AWS, customers using capacity provider strategies with mixed EC2 and Fargate compute have reduced their container costs by up to 50% compared to Fargate-only deployments (source: AWS Containers Blog, 2024).

Service-Level Decisions

Different services can use different compute:

| Service Type | Recommendation | |-------------|----------------| | Web API (steady load) | EC2 Reserved | | Web API (variable) | Fargate | | Batch Processing | EC2 Spot | | Scheduled Jobs | Fargate | | ML Inference | EC2 GPU | | Development | Fargate |

Migration Strategies

EC2 to Fargate

Evaluate task definitions for compatibility

Remove host dependencies (volumes, networking)

Update IAM roles for Fargate

Test in non-production

Gradual traffic shift with load balancer

Fargate to EC2

Create EC2 capacity with appropriate instance types

Configure auto scaling groups

Update service to use EC2 launch type

Monitor performance and adjust capacity

When choosing a container orchestration layer, the choice between ECS and EKS also impacts how you manage EC2 and Fargate compute.

Security Comparison

EC2 Security Considerations

• OS patching responsibility
• Instance hardening requirements
• Shared kernel between containers
• Network segmentation configuration
• Instance metadata protection

Fargate Security Benefits

• AWS-managed infrastructure patching
• Task-level isolation
• No shared kernel
• Reduced attack surface
• Simplified compliance

For a deeper look at securing your AWS workloads, explore our guide on AWS security services.

How BeyondScale Can Help

At BeyondScale, we specialize in cloud infrastructure implementation and container strategy. Whether you're evaluating EC2 vs Fargate for a new project or optimizing costs on an existing container platform, our team can help you design the right architecture and execute a smooth deployment.

Explore our Implementation Services to learn more.

Conclusion

The choice between EC2 and Fargate depends on your specific requirements:

• Choose EC2 for cost optimization at scale, specialized hardware needs, and when you need full control
• Choose Fargate for operational simplicity, variable workloads, and when security isolation is paramount
• Consider hybrid approaches to optimize for both cost and flexibility

Start with Fargate for new projects unless you have specific requirements that necessitate EC2. As workloads mature and patterns become clear, evaluate whether EC2 would provide better economics for stable, high-volume services.

Frequently Asked Questions

How do EC2 and Fargate compare on cost for running containers?

EC2 is generally more cost-effective at scale, especially when using Reserved Instances (up to 72% savings) or Spot Instances (up to 90% savings). Fargate eliminates idle capacity charges and is simpler to budget, but for steady-state workloads it can cost 40-70% more than an optimized EC2 deployment.

When should I use Fargate instead of EC2 for containers?

Fargate is ideal for teams without dedicated DevOps engineers, variable or unpredictable workloads, development and testing environments, and quick prototypes. It removes the operational burden of patching, scaling, and managing EC2 instances, letting your team focus on application development.

What is the container management overhead difference between EC2 and Fargate?

EC2 requires you to manage instance patching, capacity planning, auto-scaling groups, and security hardening at the OS level. Fargate eliminates all host-level management entirely, meaning you only need to define your container task definitions and let AWS handle the rest.

What are the main limitations of AWS Fargate?

Fargate does not support privileged containers, custom AMIs, host networking mode, or direct host access. GPU support is limited compared to EC2, and you cannot use instance store volumes. These restrictions make EC2 necessary for workloads that require specialized hardware or low-level operating system access.

Can I use both EC2 and Fargate together in the same ECS cluster?

Yes, ECS capacity providers allow you to run both EC2 and Fargate in the same cluster. This hybrid approach lets you maintain cost-efficient EC2 Reserved Instances for baseline capacity while automatically bursting to Fargate during peak demand, giving you the best of both worlds.