I don't know why you are being downvoted, it seems like a legitimate question to me. I routinely edit text files that are hundreds of megabytes, and sometimes

I don't know why you are being downvoted, it seems like a legitimate question to me. I routinely edit text files that are hundreds of megabytes, and sometimes over a gig. These are usually transcripts from chip simulations, where I'm tracking down where something went wrong. Most often I do this in emacs, and sometimes vim. They both do fine with it, although emacs used to warn about files over a certain limit. It has always done fine with them in practice.