Understanding the 90th Percentile in Performance Testing

The 90th percentile (90th LE – Last Execution) is a crucial metric in performance testing, representing the point below which 90% of user transactions fall. By focusing on this metric, testers gain insight into the typical user experience.

Positives:

1. Reflects Majority Performance: Provides a realistic view of system performance under normal conditions.
2. 2. Identifies Common Bottlenecks: Helps pinpoint performance issues affecting a significant portion of users.
3. 3. Balanced Approach: Strikes a balance between considering outliers and typical user behavior.

Negatives:

1. May Miss Extreme Cases: Overlooks performance issues experienced by critical user segments.
2. 2. Limited Visibility into Outliers: Does not fully account for performance outliers beyond the 90th percentile.

Implementation Steps:

1. Gather performance data.
2. 2. Calculate the 90th percentile.
3. 3. Analyze performance bottlenecks.
4. 4. Optimize system based on findings.