What is the Performance Criteria?
It is important to ascertain the permissible performance criterion before attempting performance tuning. For Web servers, it is usually the number of requests served each second at a certain load condition. It is crucial to establish the performance criteria in terms of the expected load range on Server and permissible response time.
Permissible response time is difficult to establish as it is qualitative and cannot be determined as a single unique value across all types of requests. Most applications have sections or modules that follow different load characteristics. For example, applications usually contain general public domain content that is static in nature. There might be some dynamic content such as database operations.
Note: More sophisticated testing mechanisms might determine different load conditions for each module. It is important to lay down the requirements against which the exercise would be carried out.
