Optimize requires for non-omnibus installs

[tas50]

require is quite slow in Ruby and doing requires for things you've already required is also slow. We've used this simple hack in Chef to speed up our requires. In the omnibus installs we patch how rubygems works to make this somewhat pointless, but this will help non-omnibus installs

Signed-off-by: Tim Smith tsmith@chef.io

[djberg96]

@tas50 I don't know if it's of any interest to you now, but I think require uses File.expand_path under the hood, which I improved here: https://github.com/djberg96/win32-xpath.

I could be wrong, but I'd be curious to see some require benchmarks with and without win32-xpath.

[lamont-granquist]

Yeah we've "locally" patched ruby to remove some excessive "expand_pathing" going on. Although its here where it calls rb_realpath_internal: https://github.com/chef/omnibus-software/pull/1129/files