This graph is helpful in estimation of per request resources needed to support studied traffic. The graph shows the variation of the Document Hit Ratio and Byte Hit Ratio during the day. This graph analyzes relative impact of request processing stages. Such analysis is essential for performance optimizations since it helps in identifying performance bottlenecks. The graph shows relative contribution of each stage towards total delay.
Total delay is calculated as a sum of delays of all stages.
Note that median total delay may differ from median response time because of pipelining and such non-accounted activities as DNS lookups. We are working on a more precise model that accounts for these side effects. We cannot account for pipelining affects that may change relative contributions for large requests. We believe that our estimations are very close to actual performance. The graph shows relative contribution of each stage towards total delay.