Aruba.configure do |config| config.before_cmd do # ideas taken from: http://blog.headius.com/2010/03/jruby-startup-time-tips.html set_env('JRUBY_OPTS', '-X-C') # disable JIT since these processes are so short lived set_env('JAVA_OPTS', '-d32') # force jRuby to use client JVM for faster startup times end end