Another problem I found like n my simulation I am working with cylindrical dielectric and trying to optimize the reflection with plane wave source by changing the radius, periodicity, and height. I observed that the simulation time is not the same for all the values of height, and just by making a small change in the height value the simulation time is changing a lot like from 5ps to 30 ps. This is creating problems in the optimization process. It is taking a lot of time when I AM DOING FINE SWEEP OF THE PARAMETERS.