Hi Peter
This is just an idea and experiences of mine.

Long time ago I have to use un-estimated resource component such as
library(don`t ask me why it`s neccessary).

I have made main software and attach the library at the end but it doen`t work.The ram usage is too much while the ROM is still OK(sufficient).

I have dispatch library call function
one by one and see it growth(down) and decide which is important to my work.
So I must saw it trend and decide between more function or more RAM until I got the optimum point.

At that time I observe someting of this growth and OVERLAY directive effect.

Hope this don`t makee you annoy.

Best Regards