It's a heck of a lot easier to pore thru a huge trace file with an intelligent editor. Instead, I get to use Notepad.
The file on the screenshot is ~156MB took several seconds to load but after that all operations on it are instant.
http://img199.imageshack.us/img199/9108/emacslargefile.png
The blacked out parts are work related - sorry.
Have you tried Notepad++ or UltraEdit? Colorization, smart handling of large files, etc.?
It's a heck of a lot easier to pore thru a huge trace file with an intelligent editor. Instead, I get to use Notepad.