Blog Details

Reyki AI Explains: The Difference between Cloud Computing Autoscaling vs. Rightsizing


In the ever-evolving world of cloud computing, resource optimization is key to managing costs and ensuring the best performance for your applications. Two strategies that play a crucial role in achieving this are autoscaling and rightsizing. In this article, we will delve into the differences between these two approaches, with a focus on examples from Amazon Web Services (AWS).

Autoscaling: Dynamic Resource Adjustment

Autoscaling is a fundamental technique that allows cloud users to automatically adjust the number of resources in their infrastructure based on the current workload. The goal is to ensure that you have enough resources to meet demand while avoiding over-provisioning. AWS provides a powerful autoscaling service that's well-suited for this purpose.

Example 1: AWS Elastic Beanstalk

Suppose you're running a web application using AWS Elastic Beanstalk. During normal business hours, your application experiences heavy traffic, and during off-peak hours, the traffic is significantly lower. By setting up autoscaling, you can dynamically add or remove instances to match your application's current traffic load. This ensures that you are always using the right amount of resources, neither too many nor too few.

AWS Elastic Beanstalk allows you to configure Auto Scaling based on metrics such as CPU utilization, requests per second, or custom metrics tailored to your application. When thresholds are met, it automatically provisions or de-provisions instances, maintaining the desired performance level.

Example 2: AWS Auto Scaling Groups

Another AWS service that emphasizes autoscaling is Auto Scaling Groups. Let's say you manage a fleet of EC2 instances to host a web service. With Auto Scaling Groups, you can define scaling policies that automatically add or remove instances based on CPU utilization, network traffic, or custom CloudWatch alarms. This ensures that your application's performance remains consistent while optimizing your costs.

Rightsizing: Efficient Resource Allocation

Rightsizing, on the other hand, focuses on making sure that the resources you're using are the right size for your specific workloads. This means selecting the appropriate instance types and sizes to maximize efficiency and minimize costs.

Example 1: EC2 Instance Types

Imagine you are running a data processing application on AWS EC2 instances. If you choose instances that are too large for your workloads, you will be overpaying for unused capacity. Conversely, selecting instances that are too small might lead to performance issues. By performing rightsizing analysis, you can choose the optimal instance type and size that fits your application's requirements, balancing cost and performance.

For instance, if your application requires high memory but not a substantial amount of CPU power, you might select an R5 instance type instead of a more expensive, CPU-optimized instance like C5. By doing so, you optimize your resource allocation while reducing costs.

Example 2: AWS Cost Explorer

AWS provides tools like AWS Cost Explorer, which can help you analyze your resource usage and identify areas for potential rightsizing. For instance, you might discover that you are using larger EBS volumes than needed or running oversized RDS database instances. By resizing these resources to match your actual workloads, you can significantly reduce your cloud expenses.

Key Differences between Autoscaling and Rightsizing

  1. Automation vs. Analysis: Autoscaling is an automated process that responds to changes in demand in real-time, while rightsizing involves a more analytical approach that requires ongoing monitoring and decision-making. This automated nature of autoscaling ensures that your resources are dynamically adjusted based on the current traffic load, providing optimal performance during traffic spikes.
  2. Dynamic vs. Static: Autoscaling is dynamic and adjusts resources as demand fluctuates, ensuring that your application can handle sudden spikes in traffic without manual intervention. Rightsizing, on the other hand, is a more static approach, focusing on optimizing the size of your resources for your typical workloads. It ensures cost-efficiency during steady-state operations.
  3. Usage Patterns: Autoscaling is ideal for workloads with varying demand patterns, where resources need to flex with the load. For example, e-commerce websites often experience traffic spikes during sales events or holidays, making autoscaling a valuable tool to maintain performance. In contrast, rightsizing is best suited for workloads with relatively stable resource requirements, aiming to reduce costs by eliminating excess capacity. An example would be a database server or an analytics platform that operates with a consistent load pattern.


In the world of cloud computing, optimizing resources is essential for cost efficiency and application performance. AWS provides powerful tools and services for both autoscaling and rightsizing. The key to success is understanding when to use each strategy.

Autoscaling is ideal for applications with variable workloads, ensuring that you always have the right amount of resources, while rightsizing is critical for fine-tuning your infrastructure to maximize efficiency and reduce costs.

By combining both approaches intelligently, you can strike the right balance between cost savings and performance for your cloud-based applications on AWS. This balance will enable your applications to deliver an optimal user experience while keeping your cloud costs under control.

Reyki AI is adept at implementing a variety of cloud cost optimization techniques that help customers reduce their overall cloud bill. From reserved instance (RI) arbitrage to rightsizing to drive maximal resource utilization, customers stand to get the most out of their cloud computing at substantially lowered cost.

Start Saving Now

Book a demo to learn how much you can save