如何描述Rake任务？

ruby -Ilib -S ruby-prof -p graph_html `which rake` TASK > profile.html

ruby-prof -p graph_html /usr/local/bin/rake19 import_from_aws file=~/sourcedata batch=test1 > /tmp/profile.html

rake19 import_from_aws file=~/sourcedata batch=test1

module Rake
  class Task
    def execute_with_timestamps(*args)
      start = Time.now
      execute_without_timestamps(*args)
      execution_time_in_seconds = Time.now - start
      printf("** %s took %.1f secondsn", name, execution_time_in_seconds)
    end

    alias :execute_without_timestamps :execute
    alias :execute :execute_with_timestamps 
  end
end

ruby-prof -p graph_html `which bundle` -- 'exec' 'rake' '-T' > profile.html