1. A method of software program execution profiling, comprising: measuring variation in execution time between iterations of paths through the software program, the variation in execution time measured for multiple iterations of each path over base times for the paths; and identifying paths having higher execution time variation; wherein said measuring comprises: inserting instrumentation code into the software program; causing the software program to execute under a usage scenario; recording profiling data by the instrumentation code during said execution of the software program, the profiling data including at least execution times for at least some iterations of at least some paths of the software program; and performing a path variation analysis determining which of the paths have higher execution time variation; and wherein said performing path variation analysis comprises: determining base times of execution of the paths; determining variation times for multiple iterations of each of the paths as a difference of the execution times of the multiple iterations of each of the paths from the base times; and determining path variation times for the paths as a sum of the variation times of the multiple iterations of the respective paths.