Monitoring EBS Capacity Utilization for Better Efficiency

After addressing initial EBS optimization strategies—like deleting unattached volumes, optimizing IOPS, and choosing the right disk types—the next step is aligning storage capacity with your actual business needs. This process, known as "right-sizing," begins by monitoring actual capacity utilization. Without this, you risk paying for underutilized storage, a hidden cost driver in your AWS environment.

Capacity Utilization

Capacity utilization measures how much data is stored on your EBS volumes compared to the total storage provisioned. For steady workloads, it’s often possible to increase volume size as demand grows. However, while scaling up is straightforward, scaling down can be more challenging. Workloads that are unpredictable or session-based (like online gaming or call recordings) make it harder to estimate storage requirements. As a result, organizations tend to over-provision storage "just in case," leading to significant waste.

How to Monitor EBS Capacity Utilization?

Unlike tracking EC2 CPU usage, AWS doesn’t provide built-in metrics for EBS space usage. To monitor your actual storage usage, you’ll need to collect data at the EC2 instance level. There are a few ways to do this, however they all involve having some sort of agent on the instance itself that will collect this data. The most popular choices to do so include:

1. CloudWatch agent or AWS SSM - These are native AWS agents that allow to collect such metrics through custom CloudWatch metrics or by running OS-level commands where the volume is mounted.
2. APM agents - Such as Datadog or Prometheus, thay collect instance level data, can often collect capacity utilization as well.
3. Datafy’s “read-only” agent - You can use Datafy’s own agent in “read-only” mode which will allow you to better scope the capacity utilization problem.

Once you have this data, the next step is setting up alerts for underutilized storage, prompting timely action. For example, if utilization drops below 20%, you can configure SNS notifications to alert the FinOps or DevOps team (or ideally, the resource owner) to investigate and consider remediation options. While effective, this process can be time-consuming.

Remediation might involve deleting volumes (or other resources). While this is often the most impactful cost-saving strategy, it’s not always feasible. Alternatively, right-sizing volumes may be a solution, though this is more complex. For more on shrinking EBS volumes, you can read Datafy’s blog on  Right-Sizing Your EBS Volumes: Optimizing Storage Without Downtime.

A Smarter Approach

Since monitoring capacity utilization is challenging, many teams don’t track this metric, leaving them unaware of potential savings. For those who do, the process of tracking, alerting, and right-sizing can be slow and inefficient. With an automated tool like Datafy’s, this workflow is streamlined—providing auto-scaling solutions for your volumes without the need for constant manual oversight, saving time, and reducing team frustration.

Ready to save time and cut costs? Talk to us today to optimize your EBS automatically.