I just got my rails 2.3.8 app running on ruby 1.9.1. To get into the console, start the webserver, anything that initializes rails, takes 3 - 4 times longer in ruby 1.9 than
It's probably because ruby 1.9 uses gem_prelude (which gives you a large load path) instead of normal rubygems. Checkout the length of $: -- that gets searched once for each require, causing extra time
If you want it the old way, (upgrade to the latest version of rubygems and) run ruby --disable-gems
If you are on windows, take a look into my faster_require gem.
http://github.com/rdp/faster_require
Though I suppose, now that you mention it, it might help in 1.9 Linux. Maybe.
GL! -rp