Your program is much too trivial to draw any conclusions about compiled Perl memory usage, and it's only a single data point, at that. You also need to look deeper into the OS memory to see how much of that is shared, vss, rss, etc. (and come with an understanding of what that means).

To more accurately test, you would need to have code that uses significant memory with each of the various (Perl) reference types, and independently test the effects of code size, module dependencies, XS/I::C code, and then you'd start to get an idea for your system.

My suggestion would be to not worry about it too much and focus on writing elegant memory- and CPU-efficient code. Your gains will almost certainly be much greater on that front.