Logged In: YES 
user_id=31435

Intrigued by a comment of McIlroy, I tried catenating all 
the .c files in Objects and Modules, into one giant file, and 
sorted that.  msort got a 22% speedup there, suggesting 
there's *some* kind of significant pre-existing lexicographic 
order (and/or reverse order) in C source files that msort is 
able to exploit.

Trying it again on about 1.33 million lines of Python-Dev 
archive (including assorted uuencoded attachmets). msort 
got a 32% speedup.

I'm not sure what to make of that, but we needed some real 
life data here <wink>.