I've written a little script which will check for duplicate files by walking down my file system. That part's no problem. What is a problem is how long it takes to get md5 signatures of large files, a couple of which are zipped tar files I'm using for backups.

Right now, I'm simply skipping files that are too big (2**24 bytes or larger), which is inelegant.

So, question 1 is how does md5's execution time scale with file size? (I would expect linearly, but I'm not sure)

Question 2: Is there a similarly reliable but quicker algorithm to get a file's signature?

I'm using the md5 program that came with my computer, which is a MacBook with a 2.1 Ghz Intel Core 2 processor, 1 BG RAM, and Mac OS X 10.7.4 (don't laugh; it was free ;))

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In reply to [OT]:Faster signature algorithm than md5? by swampyankee

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