What is the Apdex threshold calculation formula?

The Apdex (Application Performance Index) threshold calculation formula is used to measure user satisfaction with application performance. It categorizes response times into three groups:

1. Satisfied: Response time is less than or equal to the T (satisfaction threshold).
2. Tolerating: Response time is greater than T but less than or equal to 4T.
3. Frustrated: Response time is greater than 4T.

The Apdex score is calculated as:

$\text{Apdex} = \frac{\text{Satisfied} + \frac{\text{Tolerating}}{2}}{\text{Total Requests}}$

Where:

• Satisfied = Number of requests with response time ≤ T
• Tolerating = Number of requests with response time > T and ≤ 4T
• Total Requests = Total number of requests

Example:

If the threshold T is set to 2 seconds:

• Requests taking ≤ 2s → Satisfied
• Requests taking > 2s but ≤ 8s → Tolerating
• Requests taking > 8s → Frustrated

A higher Apdex score (closer to 1) indicates better user satisfaction.

For cloud-based performance monitoring, Tencent Cloud's Application Performance Monitoring (APM) service can help track and analyze response times, enabling you to set optimal Apdex thresholds for your applications.