Perl isn't really an interpreted language. It's compiled to a sort of bytecode when you run the program, and executed on a sort of virtual machine. Similar to Java or C#, but much faster to compile. So fast that most people don't even know it's happening.
As for performance, it really helps if you write idiomatic Perl code. There may be more than one way to do it, but some ways are better. For example, an explicit for loop over a list has to be compiled to byte code that steps through the looping, but if you use map or grep the byte code calls a pre-written optimized function that loops as fast as code written in C would be. The more idiomatic your code is, the more optimized calls like that you get, and the faster your code will run.