use disposable ramdisks!
Recently I wrote about my dumb CPAN metafile analyzer, and how I’d tried to keep it fast. One of the things I tried to speed it up was creating a ramdisk for all of the archive extraction. The speed boost in this case turned out to be low, but it isn’t always. (Also, I inexplicably used a journaling filesystem .) When you’re doing a ton of file operations, the difference between physical storage and in-memory can be huge.