The Flat view is the default view which displays the summary of a complete and non-hierarchical list of each function profiled. No matter what calling path was used to reach a function, the profiler combines all the data for the same function and displays it on a single line. Figure 1 shows the Flat view of the profiler results.
The Flat view is particularly useful for comparing functions to check which function takes the longest time to execute. The Flat view is also useful for finding a performance problem with a small function that is called from many different places in the program. This view helps you look for the functions that make heavy demands in time or raw number of calls.