Metrics & Instrumentation: RED & USE Methodologies

Introduction

The RED (Rate, Error, Duration) and USE (Utilization, Saturation, Errors) methodologies are frameworks for monitoring system performance. These metrics help identify potential issues and improve the reliability of services.

Definitions

• RED Methodology: Focuses on three essential metrics: request rate, error rate, and request duration.
• USE Methodology: Concentrates on resource utilization, saturation, and error rates to provide insights into resource performance.

RED Methodology

The RED methodology is primarily used for services, focusing on the following key metrics:

1. Request Rate: The number of requests received by the service per time unit.
2. Error Rate: The percentage of requests that result in errors.
3. Request Duration: The time taken to process requests.

USE Methodology

The USE methodology is applied to resources (like CPU, memory, and disk) and revolves around the following metrics:

1. Utilization: The percentage of resource capacity currently in use.
2. Saturation: The degree to which resource capacity is being pushed to its limits.
3. Errors: The number of errors occurring in resource handling.

Flowchart

                graph TD;
                    A[Start] --> B{Service?};
                    B -->|Yes| C[Collect RED Metrics];
                    B -->|No| D[Collect USE Metrics];
                    C --> E[Analyze RED Data];
                    D --> E;
                    E --> F{Issues Detected?};
                    F -->|Yes| G[Alert Devs];
                    F -->|No| H[Continue Monitoring];
                

Best Practices

• Regularly review and adjust thresholds for alerts based on historical data.
• Implement automated monitoring tools to streamline data collection.
• Combine RED and USE methodologies for a holistic view of both service and resource performance.

FAQ