What is the recommended method for calculating the Service Level Indicator (SLI) for a high-traffic web application aimed at ensuring quick load times?

The recommended method for calculating the Service Level Indicator (SLI) for a high-traffic web application focused on ensuring quick load times involves measuring the number of requests that meet a specific performance threshold, making option C the correct choice. This approach provides a clear and direct assessment of how well the application is performing in terms of response time for end-users, who typically are concerned with how quickly they can load a webpage.

By counting the number of home page requests that load in under 100 ms and dividing that by the total number of home page requests, you effectively capture the proportion of users experiencing acceptable load times. This metric is critical for understanding user satisfaction and maintaining high service performance.

Other methods mentioned, like bucketizing request latencies into ranges and computing percentiles, can provide valuable statistics about performance but do not directly address the specific user experience as clearly as option C. This is particularly important for high-traffic web applications, where user perception of speed is crucial for retention and engagement. Therefore, option C’s focus on a specific load time threshold is aligned with best practices for measuring performance against user expectations.