Update benchmark to just run AR backend

benchmarks.rb

@@ -1,33 +1,13 @@
-$:.unshift(File.dirname(__FILE__) + '/lib')
-require 'rubygems'
+require 'spec/spec_helper'
 require 'logger'
-require 'delayed_job'
 require 'benchmark'
 
-RAILS_ENV = 'test'
-
-Delayed::Worker.logger = Logger.new('/dev/null')
-
-BACKENDS = []
-Dir.glob("#{File.dirname(__FILE__)}/spec/setup/*.rb") do |backend|
-  begin
-    backend = File.basename(backend, '.rb')
-    require "spec/setup/#{backend}"
-    BACKENDS << backend.to_sym
-  rescue LoadError
-    puts "Unable to load #{backend} backend! #{$!}"
-  end
-end
-
+# Delayed::Worker.logger = Logger.new('/dev/null')
 
 Benchmark.bm(10) do |x|
-  BACKENDS.each do |backend|
-    require "spec/setup/#{backend}"
-    Delayed::Worker.backend = backend
-
-    n = 10000
-    n.times { "foo".delay.length }
+  Delayed::Job.delete_all
+  n = 10000
+  n.times { "foo".delay.length }
 
-    x.report(backend.to_s) { Delayed::Worker.new(:quiet => true).work_off(n) }
-  end  
+  x.report { Delayed::Worker.new(:quiet => true).work_off(n) }
 end