Benchmarks against normal rubygems and gem_prelude in 1.9 (its normal) benchmarks runing [$ whichr whichr] (the whichr gem just behaves like the "which" command in Linux), best time seen: mingw 1.8 normal rubygems 0.77 faster_rubygems with cache 0.14 faster_rubygems without cache: 0.20 mingw 1.9 normal rubygems: 3.79 faster_rubygems with cache: 0.19 faster_rubygems without cache: 0.50 jruby, 1.8 mode normal rubygems: 2.31 faster_rubygems without cache (deleted the cache file temporarily to force it to not use it): 1.15 faster_rubygems with cache: 1.11 rails 2.3.8 [ $ ruby script\runner -e production "puts 3" ] Unfortunately rails requires a load of full rubygems. So currently faster_rubygems doesn't help it much. faster_require (other gem) seems to help, however. 1.9 normal gem_prelude[RUBYOPT=] 20.85 faster_rubygems without cache [RUBYOPT=-rfaster_rubygems] 20.7 faster_rubygems with cache [RUBYOPT=-rfaster_rubygems --disable-gems]: 12.10 normal gem_prelude, with faster_require gem [RUBYOPT=-rfaster_require]: 8.93 faster_rubygems, without cache, with faster_require [RUBYOPT=-rfaster_rubygems -rfaster_require]: 8.99 * recommend this configuration for ruby 1.9 and rails. faster_rubygems, with cache [RUBYOPT=--disable-gems -rfaster_rubygems -rfaster_require] fail (gotta fix that, then will probably be fastest option) 1.8 normal rubygems: 6.54 faster_rubygems without cache: 6.12 faster_rubygems with cache: 6.48 normal rubygems, faster_require: 3.53 faster_rubygems with cache and with faster_require (have to use it as require 'faster_require') 2.97 * recommend this configuration, which means you'll have to add a require 'faster_require' to your rails script at the beginning, like in boot.rb faster_rubygems without cache and with faster_require 3.31 TODO: jruby spawning itself was *so slow* it seemed (timer.rb) only regenerate appropriate cache files after gem installs...I guess. only cache lib filenames, not spec files, et al... chmod after create (check if necessary first)