subject: Load Tests Need To Be Realistic [print this page] It is use less to have load test that does not reflect the actual usage and this will be dangerously misleading. For ex: this could give you the information that is either a overestimate or an underestimate of the website capacity and scalability leading to disastrous consequences.
Metrics are used systematically to design, develop and test load scenarios that simulate, as accurately as possible, real load situations. To measure how closely a load test matches real world usage, we developed the concept of Web site Usage Signature (WUS). The WUS is a set of metrics and measurements that, taken collectively, yield a very comprehensive picture of Web site activity.
If the WUS from a load test does not match closely the WUS from actual usage, you should seriously question the validity and applicability of any conclusion drawn from the tests. Conversely, if the two WUSs are well matched, then your level of confidence that any results apply to real world situations increases considerably. Since every Web site is unique and needs to track site-specific metrics, there is no standard format or standard set of metrics for the WUS.
Another important thing is to include enough measurements to make it difficult for two signatures to match closley unless the two leads are closely matched. Having realistic load tests greatly simplifies the task of creating and testing load senarios.
Latency tolerance is an indicator of how long a user will wait for a page to load before becoming dissatisfied and, possibly, abandon the Web site. A load scenario can be made significantly more realistic by simulating the behavior of tolerant and intolerant users.
