[Confusion]

It's definitely noticably slower, but 4 seconds per startup would make it unusable for me. However, since it's

  time jruby -e 1
  real	0m0.514s
  user	0m0.510s
  sys	0m0.040s

I find it acceptable (could it be the SSD in my laptop that makes such a large difference?). As http://jira.codehaus.org/browse/JRUBY-5181 shows, as soon as some gems come into the picture, actual startup times deteriorate rapidly.

[tptacek]

I'm not an SSD, but mine was also a cold start; are you sure yours wasn't already cached?

[Confusion]

I don't reboot that often, so it took me a while before I could try it, but my home desktop, also with SSD, gives

  user@twen:~/tmp$ time jruby -e '1'

  real	0m0.664s
  user	0m0.390s
  sys	0m0.110s

for a cold boot. Subsequent startups are 350-400ms. Stock JRuby 1.5.6