I found global-linum-mode to be rather slow in large files, unfortunately. Are there better alternatives that show the number for each line? At the moment, I’m using column-number-mode to see the current line/column in the status bar, but I’m not too happy with it.
I know it's probably a personal preference thing, but do you really need line numbers? I've never missed them. Even if I'm not jumping to a compile error (or grep result, etc) with M-g n, I can always go to a particular line with M-g g, or show what line the cursor is on with what-line. I've also got flymake next and previous warnings mapped to similar keys.