What Is the USE Method?

USE Method is a performance analysis methodology created by Brendan Gregg that monitors infrastructure resources by tracking three metrics: Utilization (percentage of time the resource is busy), Saturation (degree of queued work), and Errors (count of error events). Unlike the RED method which focuses on services, USE focuses on underlying infrastructure resources like CPU, memory, disk, and network interfaces.

Why the USE Method Matters

Application-level metrics like RED show symptoms but not always the root cause. When a service is slow, the USE method helps identify whether the cause is CPU contention, memory pressure, disk I/O saturation, or network bottlenecks. By systematically checking utilization, saturation, and errors for every resource, you can quickly pinpoint infrastructure-level problems that affect application performance.

Teams that understand and adopt use method gain a significant operational advantage, reducing manual effort and improving the reliability and scalability of their infrastructure. As cloud-native adoption accelerates, familiarity with use method has become a core competency for DevOps engineers, platform teams, and site reliability engineers working in production Kubernetes and cloud environments.

How the USE Method Works

For every physical and software resource in your system, check three things. Utilization tells you what percentage of capacity is being used. Saturation tells you whether work is queuing because the resource cannot keep up. Errors tell you whether the resource is producing error events. This systematic approach ensures no resource bottleneck is missed. In Kubernetes, this applies to CPU, memory, disk I/O, and network for each node and pod.

Understanding how use method fits into the broader cloud-native ecosystem is important for making informed architecture decisions. It works alongside other tools and practices in the DevOps and platform engineering space, and choosing the right combination depends on your team's specific requirements, scale, and operational maturity.

Key Features

Utilization

Percentage of resource capacity in use. High utilization indicates the resource may become a bottleneck soon.

Saturation

Degree to which extra work is queued. Saturation above zero means the resource is overloaded and requests are waiting.

Errors

Count of error events from the resource. Even lightly utilized resources can have errors affecting performance.

Systematic Coverage

Apply USE to every resource systematically to ensure no bottleneck goes undetected in your infrastructure.

Common Use Cases

Diagnosing slow pod performance by checking CPU utilization, memory saturation, and disk I/O errors on the host node.

Creating Grafana dashboards that display USE metrics for every Kubernetes node to identify infrastructure bottlenecks.

Combining USE method for infrastructure with RED method for services in a comprehensive observability strategy.

Troubleshooting network latency by checking network interface utilization, packet queue saturation, and dropped packets.

How Obsium Helps

Obsium's managed observability team helps organizations implement and optimize use method as part of production-grade infrastructure. Whether you are adopting use method for the first time or looking to improve an existing implementation, our engineers bring hands-on experience across cloud platforms and Kubernetes environments. Learn more about our managed observability services →