These days Emacs without extra packages uses less memory than pretty much everything other than vi (not so sure for vim but if it's using less that won't last with slop), ed, nano and the micro/mini Emacs derivatives like zile & mg.
If you want to use an absolute minimum of resident memory add:
```
(when (symbol-function 'malloc-trim)
(add-hook 'post-gc-hook #'malloc-trim))
```
to your configuration file.
This means that the GC releases the memory to the system in full when it does its pass, instead of just using `free()` and having the libc `malloc` cache artificially bloating its memory (sometimes by gigabytes depending on what you're doing).
One of my Emacs instances with a few thousand buffers open currently uses 310MB resident.
