The search-based tools initially identify the problem and after that appropriately give advice on how to correct it.
AT Expert from Cray Research is one of the tools being used for increasing the performance of FORTRAN programs with the help of a set of rules which have been written with Cray auto-tasking library. The Cray auto-tasking library helps in achieving the parallelism. Mostly, the ATExpert analyses the FORTRAN program and tries to recommend complier directives that could help in improving the performance of the program.
One more tool called "Performance Consultant" is independent of any programming language, machines and, model. It mostly asks three questions i.e. WHY, WHERE and WHEN about the performance bottlenecks and overheads. These three questions form the 3 dissimilar axes of the hierarchal model. One of the main features of Performance Consultant tool is that it seeks for bottlenecks during implementing of program. The above- mentioned features assist in maintaining the reduced volume of data. The WHY axis presents the several bottlenecks such as communication, I/O etc. The WHERE axis describes the several sources which can cause bottlenecks such as Interconnection networks, CPU etc. The WHEN axis tries to divide the set of bottlenecks into a specific phase of implementation of the program.