February 7, 2024

The Ultimate EKS Cost Optimization Guide for 2024

4 min read

The Ultimate EKS Cost Optimization Guide for 2024
The Ultimate EKS Cost Optimization Guide for 2024
The Ultimate EKS Cost Optimization Guide for 2024


Amazon Elastic Kubernetes Service (EKS) stands as a pivotal service within the cloud infrastructure ecosystem, offering a managed environment to run Kubernetes on AWS without the need for installing or operating your own Kubernetes control plane. EKS streamlines the process of deploying, managing, and scaling containerized applications using Kubernetes, which is an open-source system designed for orchestrating containerized applications across a cluster of machines.

The Significance of EKS

The significance of EKS cannot be overstated in the realm of cloud services. It provides a robust, scalable foundation that enables businesses to:

  • Deploy applications quickly and efficiently

  • Ensure high availability and reliability

  • Scale workloads in response to changing demands

With the digital transformation accelerating at unprecedented rates, there's been a noticeable surge in the adoption of containerization and orchestration technologies. EKS has become increasingly popular among organizations looking to leverage the benefits of Kubernetes without the complexity of managing it. The rising adoption underscores the need to focus on EKS cost optimization strategies. As companies invest more in these services, optimizing EKS cost becomes imperative to maximize return on investment while maintaining operational excellence.

Understanding Kubernetes Costs with EKS

When considering Kubernetes costs, it's important to note that while EKS simplifies many aspects of running Kubernetes, it also introduces various pricing components that can impact your overall cloud expenses. Effective management and optimization of these costs are crucial in ensuring that you're not overspending on resources that your workloads don't require.

This guide delves into an array of strategies aimed at enhancing cost efficiency within your EKS deployments. Here are some key techniques we will explore:

  • Analyzing cluster component charges: Understand where your money goes and how to cut unnecessary expenses.

  • Right-sizing EC2 instances: Align instance types and sizes with workload needs to avoid overspending.

  • Leveraging autoscaling: Use AWS's autoscaling features to adjust resources dynamically based on demand.

  • Embracing Spot Instances: Capitalize on discounted pricing for interruptible compute capacity.

  • Optimizing with AWS Fargate: Explore serverless computing options for potential labor cost savings.

  • Minimizing data transfer costs: Implement network efficiencies to reduce outbound data transfer fees.

  • Employing savings plans and reserved instances: Commit to specific usage for significant discounts over time.

The techniques covered aim at striking a balance between cost savings and maintaining both performance and reliability. By applying these methods, organizations can achieve more with less, ensuring their EKS deployments are both economically efficient and robust enough to support their operational goals.

Understanding EKS Costs

Amazon Elastic Kubernetes Service (EKS) is a managed service that simplifies the process of running Kubernetes on AWS without needing to install, operate, and maintain your own Kubernetes control plane or nodes. It comes with key features such as:

  • Managed Kubernetes Control Plane: EKS automates tasks such as patching, node provisioning, and updates.

  • Security: Integrates with AWS Identity and Access Management (IAM) for authentication.

  • High Availability: Automatically runs across multiple AWS Availability Zones to avoid a single point of failure.

Pricing Components

To effectively manage their EKS costs, users need to understand the various pricing components involved:

  • EKS Cluster Creation: Users pay a fee for each hour that their EKS cluster runs.

  • Compute Resources: Charges are based on the EC2 instances or Fargate resources used by the Kubernetes worker nodes.

  • Data Transfer: Costs associated with data transfer within and outside AWS regions.

The Role of AWS Well-Architected Framework

The AWS Well-Architected Framework plays a vital role in guiding cost optimization efforts for EKS. This framework recommends best practices and strategies to help build efficient systems on AWS.

When applied to EKS, it emphasizes:

  • Cost Optimization Pillar: Focuses on avoiding unnecessary costs, understanding and controlling where money is being spent.

  • Resource Efficiency: Ensures that you are using the most cost-effective resources and scaling patterns for your workload.

  • Performance Efficiency Pillar: Looks at how to use computing resources efficiently to meet system requirements.

By applying the principles of the Well-Architected Framework, organizations can design and operate cost-efficient architectures that will scale with business needs without wasting resources.

In the next section, we will analyze the cluster component charges and offer concrete ways to put these principles into action.

  1. Analyzing and Optimizing Cluster Component Charges

    The first step towards optimizing your EKS costs is analyzing and understanding the charges associated with your cluster components. The primary component that incurs cost in an EKS cluster is the EC2 instances that serve as worker nodes. The cost of EC2 instances depends on their size, type, and lifecycle (on-demand or reserved).

    1. Right-Sizing EC2 Instances

      Right-sizing is an essential practice when it comes to cost optimization in EKS. It revolves around the idea of matching the size and power of your EC2 instances to the needs of your workloads. When you right-size, you ensure that you are not overpaying for resources that your applications do not use.

      Right-sizing technique involves two critical steps:

      • Analyzing Workload Requirements: Understanding the resource requirements of your workloads is crucial to right-sizing. Tools like AWS CloudWatch can help monitor resource usage and identify trends over time.

      • Choosing the Right Instance Type: Once you understand your workload requirements, choose an EC2 instance type that closely matches these requirements. Remember, smaller does not always mean cheaper in cloud computing due to factors such as increased CPU load or network I/O.

      For example, if a workload only uses half of an m5.large instance's CPU capacity, switching to an m5.medium instance might be more cost-effective.

      Notably, right-sizing can reduce both direct costs (instance hours) and indirect ones such as labor costs associated with managing larger clusters.

      Exploring Spot Instances

      An effective way to further save on EC2 instance costs is by leveraging Spot Instances. These are spare Amazon EC2 compute capacity available at up to 90% off compared to On-Demand prices.

      Spot instances are particularly effective for fault-tolerant and flexible workloads due to their interruptible nature. Some use cases include:

      • Batch jobs

      • Data analysis

      • Stateless web servers

      To ensure workload stability while using Spot Instances, you can use the kube-spot-termination-notice-handler. This tool drains the Kubernetes nodes when AWS plans to reclaim the instance, thereby preventing sudden workload crashes.

      Implementing EC2 Cost Optimization Techniques

      In addition to right-sizing and using spot instances, there are other EC2 cost optimization techniques you can employ.

      Reserved Instances

      Reserved Instances (RIs) offer significant discounts (up to 75%) for upfront commitments to specific instance types over a one or three-year term. They are ideal for predictable workloads with steady-state usage.

      To maximize savings with RIs:

      • Start by purchasing RIs for your base load.

      • Then supplement these with On-Demand instances or Spot Instances during peak loads.

      This strategy ensures that you achieve a balance between cost savings and workload flexibility.

      Through careful analysis and optimization of cluster component charges, significant cost reductions can be realized without negatively impacting performance or reliability.

    2. Leveraging Autoscaling Mechanisms for Cost Efficiency

      Autoscaling is a pivotal feature within Amazon EKS that dynamically adjusts the number of EC2 instances in your Kubernetes cluster. This flexibility is essential for aligning costs with actual usage, ensuring you pay only for the compute resources you need.

      EC2 instances are often a significant portion of expenses in a Kubernetes environment. By scrutinizing instance hours, you can pinpoint inefficiencies and implement changes to reduce costs without impacting performance.

      Utilizing Cluster Autoscaler

      Cluster Autoscaler plays an integral role by monitoring and scaling the number of nodes in your cluster based on demand. Below are best practices for configuring it:

      Assess Workload Patterns

      Analyze your workload demand trends to set appropriate thresholds for scaling.

      Resource-Based Scaling

      Configure autoscaling policies around CPU and memory utilization metrics to prevent over-provisioning.

      Buffer Nodes

      Maintain a small number of idle buffer nodes to handle sudden spikes without delay.

      Best Practices for Horizontal Pod Autoscaler (HPA)

      HPA focuses on the application layer, adjusting the number of pod replicas in response to changing load:

      Metric Selection

      Choose relevant metrics such as CPU or memory usage for scaling decisions.

      Fine-Tuning Thresholds

      Set precise thresholds for scaling up or down to avoid unnecessary fluctuations.

      Stability Window

      Implement a stability window to prevent HPA from making rapid, frequent changes that could destabilize your application.

      Leveraging EC2 Auto Scaling Groups

      EC2 Auto Scaling groups complement Cluster Autoscaler and HPA by providing additional cost optimization opportunities:

      Scheduled Scaling

      Use scheduled actions to scale resources in anticipation of known load changes, like nightly batch processing jobs.

      Lifecycle Hooks

      Implement lifecycle hooks to perform custom actions before instances are launched or terminated, ensuring smooth transitions.

      Spot Instances Integration

      Integrate Spot Instances into your Auto Scaling groups for cost-effective scaling during less critical workloads.

      By applying these autoscaling mechanisms, you can maintain optimal performance while minimizing instance hours and EC2 costs. The key lies in continuously monitoring and adjusting configurations based on your evolving needs.

      Remember, effective autoscaling not only reduces costs but also enhances reliability by adapting resource allocation in real-time, catering seamlessly to user demands. This approach to cost efficiency is critical in today's dynamic cloud environments where workloads can rapidly change.

  2. Optimizing Instance Hours and Pod Resources in EKS

    Effective EKS cost optimization hinges on efficient management of instance hours and pod resources. These components are significant contributors to the overall cloud spend, and their judicious use can lead to substantial cost savings.

    1. Embracing Spot Instances for Cost-Effective Workloads

      Spot Instance Pricing Model Spot Instances allow users to take advantage of unused EC2 capacity at a fraction of the usual price, with discounts up to 90% compared to On-Demand rates. The pricing model is dynamic, with costs fluctuating based on supply and demand for EC2 capacity.

      Benefits for EKS Workloads:

      • Substantial Cost Reductions: For workloads with flexible start and end times or those able to handle interruptions, Spot Instances can significantly lower compute costs.

      • Scalability: Spot Instances can be scaled quickly, providing the ability to handle burstable workloads without a hefty price tag.

      • Diverse Instance Types: Users have access to a wide range of instance types, which can be beneficial for optimizing performance and costs according to specific workload requirements.

    2. Leveraging Spot Instances Effectively

      While Spot Instances offer notable cost advantages, they require a strategy that acknowledges their transient nature.

      Strategies for Stability and Availability:

      • Spot Instance Interruption Handling: Implement automation tools like kube-spot-termination-notice-handler which listen for EC2 Spot Instance interruption notices and gracefully reschedule affected pods.

      • Fallback Strategies: Design systems with fallback options such as On-Demand Instances or Reserved Instances that can quickly replace Spot Instances if they're terminated.

      • Capacity-Oriented Scheduling: Use the Kubernetes scheduler's capability to spread pods across different types of instances and availability zones. This diversifies risk and ensures more stable operations.

      • Resource Buffering: Maintain a buffer of resources so that if some Spot Instances are lost, the remaining instances can handle the workload until replacements are provisioned.

      • Pod Disruption Budgets: Define Kubernetes Pod Disruption Budgets (PDBs) to limit the number of concurrently disrupted pods during voluntary disruptions, maintaining high availability.

      By integrating these considerations into an EKS deployment, organizations can harness the cost-efficiency of Spot Instances while maintaining robust workload performance.

      Example Use Case: A media company uses Spot Instances for its video processing workload which is tolerant to delays. They set up a Kubernetes cluster with a mix of On-Demand and Spot Instances using an Auto Scaling group. Their configuration includes PDBs ensuring at least 70% availability during disruptions and automated scaling based on demand. By doing so, they reduce their EC2 costs by over 60% without impacting their service level agreements (SLAs).

      With careful planning around usage patterns and disruption management, embracing Spot Instances emerges as a cornerstone of EKS cost optimization strategies.

    3. Leveraging Fargate for Labor Cost Savings in EKS

      AWS Fargate revolutionizes the way developers deploy and manage applications on Amazon Elastic Kubernetes Service (EKS) by abstracting away the server management aspect. This serverless compute engine allows teams to focus on designing and scaling applications without the overhead of managing underlying infrastructure, leading to significant labor cost savings.

      Labor Cost Savings with AWS Fargate
      • Simplified Operations: Without the need to provision and manage servers, operational complexity is drastically reduced.

      • Developer Productivity: Engineers can concentrate on their core application logic, enhancing productivity and innovation.

      • Maintenance Reduction: The automated scaling and management of infrastructure lower the necessity for ongoing maintenance tasks.

    4. AWS Fargate Pricing Structure

      AWS Fargate prices are based on the actual vCPU and memory resources consumed by your EKS pods, making it essential to understand their pricing model:

      • Pay-as-you-go: You pay only for the resources each pod utilizes, with no upfront fees or long-term commitments.

      • Resource-Based Billing: Costs directly correlate with the vCPU and memory that your applications require.

      Fargate Cost Optimization Strategies

      To maximize cost efficiency with AWS Fargate, consider these strategies:

      • Optimize Pod ResourcesEvaluate your workloads and allocate only the necessary vCPU and memory to your pods.

      • Continuous monitoring tools can help adjust allocations based on real-time workload demands.

      • Downscaling DeploymentsImplement policies to downscale or terminate non-essential deployments during low traffic periods or non-business hours.

      • Utilize Kubernetes native features like cron jobs for scheduling scale-down operations effectively.

      • Spot Instance IntegrationCombine AWS Fargate with Spot Instances in hybrid EKS implementations for workloads that can tolerate interruptions.

      • This integration can lead to a balanced approach between cost-effectiveness and reliability.

      EKS Cluster Optimization with Fargate

      By leveraging AWS Fargate within an EKS environment, organizations benefit from:

      • Reduced instance hours: By offloading container workloads to AWS Fargate's serverless infrastructure, you avoid incurring costs from underutilized instances.

      • Enhanced efficiency: Optimal resource utilization leads to a more cost-effective deployment without sacrificing performance.

      In summary, AWS Fargate presents a compelling option for organizations looking to streamline their EKS deployments while achieving labor cost savings. Its pay-as-you-go model aligns closely with usage, providing financial clarity and predictability. When strategically employed alongside other EKS cost optimization measures such as Spot Instances and pod resource tuning, AWS Fargate becomes an instrumental part of a comprehensive cost management strategy.

  3. Minimizing Data Transfer Costs and Optimizing Network Activity in EKS

    Data transfer costs can significantly impact the overall expense of operating Amazon Elastic Kubernetes Service (EKS) clusters. To mitigate these costs, it's crucial to streamline network activity and adopt efficient data routing strategies.

    VPC Peering and Transit Gateways

    Virtual Private Cloud (VPC) peering and transit gateways are instrumental in reducing data transfer costs:

    VPC Peering

    This networking connection between two VPCs enables you to route traffic using private IP addresses, avoiding AWS backbone networks and associated costs. In EKS, implementing VPC peering between clusters or with other AWS services can lead to substantial cost reductions.

    Here's how VPC peering aids in cost-saving:

    • Eliminates the need for Internet Gateway data transfer fees

    • Reduces latency by leveraging direct connections

    • Decreases charges associated with cross-region or cross-account transfers when configured properly

    Transit Gateways

    They act as a hub that controls how traffic is routed among connected VPCs and other services. For large-scale EKS implementations, transit gateways optimize network architecture by simplifying interconnectivity and potentially lowering costs through aggregated data transfer pricing.

    Benefits of using transit gateways include:

    • Centralized management of network routing rules

    • Scalability without a linear increase in complexity or cost

    • Reduced inter-VPC data transfer charges due to efficient routing

    Caching Strategies

    Caching strategies are vital for enhancing performance while cutting down on network costs within EKS environments:

    • Application-Level Caching: Implementing caching at the application layer reduces the need to retrieve fresh data from external sources, hence decreasing outbound network calls which incur charges.

    • Content Delivery Networks (CDNs): Using CDNs like Amazon CloudFront can cache content closer to end-users, thereby minimizing origin fetches that contribute to EKS network costs.

    • In-Memory Data Stores: Solutions like Amazon ElastiCache offer high-throughput, low-latency caching systems that keep frequently accessed data in-memory, reducing reliance on slower, more costly database queries.

    By leveraging these techniques, organizations can achieve a more efficient use of resources within their EKS clusters. This not only optimizes network activity but also aligns with the principles of cost-effectiveness and performance excellence advocated by the AWS Well-Architected Framework.

  4. Leveraging Compute Savings Plans and Reserved Instances for Cost Optimization

    The strategic use of AWS compute savings plans and reserved instances forms an integral part of EKS cost reduction. By understanding these options, you can unlock potential benefits for long-term cost optimization in your EKS environments.

    AWS Compute Savings Plans: Flexible Pricing for Cost Reduction

    AWS Compute Savings Plans are a flexible pricing model that offers significant discounts on AWS compute usage. This model applies to a wide range of AWS services, including EKS, and provides up to 66% savings compared to on-demand prices.

    Designed with simplicity in mind, Compute Savings Plans offer:

    • An hourly commitment for one or three years

    • Lower costs than On-Demand Instances

    • Application across any instance family or region

    The value proposition here is consistency and predictability in spending, which is beneficial for businesses with steady workloads and long-term projects.

    Reserved Instances: Capacity Reservation for Steady-State Workloads

    On the other hand, Reserved Instances (RIs) provide an option to reserve EC2 capacity for steady-state workloads in EKS clusters, offering up to 75% lower prices than On-Demand instances. They come with either a one-year or three-year term commitment.

    Key features of Reserved Instances include:

    • Capacity reservation when used in a specific Availability Zone

    • Flexibility to change families, OS types, and tenancies

    • Discounts applied to instances running within the instance family in any region if no capacity reservation is needed

    Choosing between Compute Savings Plans and Reserved Instances largely depends on your workload patterns and business needs. If your focus is on flexibility across multiple services, Compute Savings Plans could be a better fit. Conversely, if the primary concern is securing capacity for predictable usage in EKS environments, Reserved Instances should be considered.

    By leveraging these options strategically, businesses can achieve substantial cost efficiencies while maintaining high-performance standards for their EKS workloads.

Continuous Analysis and Optimization of Pod Metrics in EKS

When it comes to maintaining efficiency within an EKS environment, the ongoing monitoring of pod metrics is indispensable. This continuous analysis allows for optimal resource utilization and cost-effectiveness.

Strategies to Avoid Overprovisioning of Worker Nodes

With the help of Kubernetes scaling mechanisms, one can fine-tune the resource allocation on the basis of real-time usage statistics. Through the following strategies, you can avoid overprovisioning of worker nodes:

  • Establishing Accurate Pod Requests: Pod requests should align with the actual resource requirements of your workloads. Setting these values too high leads to underutilization and wasted resources.

  • Setting Appropriate Pod Limits: While pod limits prevent resource hogging by a single pod, they must be defined judiciously to avoid throttling and potential performance issues.

A point worth noting is that Kubernetes schedules pods based on their requests, not limits. Thus, setting accurate requests is essential to prevent overprovisioning of nodes.

To illustrate this, consider a scenario where two pods with request values of 1 CPU each are running on a node with 2 CPUs. Even if both pods have a limit value of 2 CPUs, Kubernetes won't schedule any new pods on this node as it acknowledges that the requested resources are fully utilized.

This process underscores the importance of setting accurate pod requests and limits - not only for ensuring efficient resource utilization but also for optimizing costs associated with worker nodes in your EKS environment.

Monitoring Tools for Enhanced Efficiency

Various monitoring tools such as Prometheus and Grafana can be employed for collecting and visualizing pod metrics in real-time. These tools provide valuable insights into your workload patterns, thereby helping you set more precise pod requests and limits.

By leveraging automation tools like kube-downscaler, you can dynamically scale down unnecessary pods during non-peak hours or weekends, thus reining in additional costs.

In essence, continuous analysis and proactive optimization of pod metrics forms the backbone of EKS cost optimization. It enables you to maintain an efficient, high-performing, and cost-effective Kubernetes environment.


Building a robust EKS cost optimization strategy is essential in today's cloud-centric environment. The techniques and best practices discussed provide a roadmap for reducing expenses while maintaining high performance and reliability within your EKS clusters.

Here are the key takeaways to remember:

  • Employ right-sizing EC2 instances and embrace Spot Instances to align costs with actual usage.

  • Configure autoscaling mechanisms like Cluster Autoscaler and HPA to ensure efficiency without sacrificing service availability.

  • Explore the potential of AWS Fargate for serverless compute options, balancing operational management with cost-effectiveness.

  • Minimize data transfer costs by optimizing network configurations and implementing effective caching strategies.

  • Commit to long-term savings with Compute Savings Plans and Reserved Instances, particularly for predictable workloads.

By combining these approaches, tailored to the unique demands of your workloads, you can achieve significant cost savings. Implementing an ongoing process of monitoring, analyzing, and adjusting will ensure that your EKS infrastructure remains both cost-efficient and optimally performing. Adopting such a comprehensive approach towards EKS cost management will not only streamline operations but also drive business growth through smarter resource allocation.

Looking to understand your EKS utilization and costs better. Talk to Amnic today. Amnic’s cloud cost observability platform allows you to measure and rightsize your cloud costs, giving you complete control over your cloud bills. 

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