profiling enabled under JRuby. Added documentation for workaround described in JRUBY-5650.

activesupport/lib/active_support/testing/performance/jruby.rb

@@ -16,9 +16,7 @@ module ActiveSupport
       protected
         def run_gc
           ManagementFactory.memory_mx_bean.gc
-        end
-        
-      class Performer; end        
+        end   
 
       class Profiler < Performer
         def initialize(*args)
@@ -33,9 +31,6 @@ module ActiveSupport
             full_profile_options[:runs].to_i.times { run_test(@metric, :profile) }
           end
           
-          profile_printer = JRuby::Profiler::GraphProfilePrinter.new(@data)
-          profile_printer.printProfile(STDOUT)
-          
           @total = @data.getDuration / 1000 / 1000 / 1000.0 # seconds
         end
 

activesupport/lib/active_support/testing/performance/rubinius.rb

@@ -84,19 +84,19 @@ module ActiveSupport
           end
         end
 
-        class Memory < DigitalInformationUnit
+        class Memory < DigitalInformationUnit          
           def measure
             loopback.get("system.memory.counter.bytes").last
           end
         end
 
-        class Objects < Amount
+        class Objects < Amount          
           def measure
             loopback.get("system.memory.counter.objects").last
           end
         end
 
-        class GcRuns < Amount
+        class GcRuns < Amount          
           def measure
             loopback.get("system.gc.full.count").last + loopback.get("system.gc.young.count").last
           end

activesupport/lib/active_support/testing/performance/ruby.rb

@@ -21,8 +21,6 @@ module ActiveSupport
         def run_gc
           GC.start
         end
-              
-      class Performer; end
 
       class Profiler < Performer
         def initialize(*args)
@@ -128,28 +126,28 @@ module ActiveSupport
           Mode = RubyProf::MEMORY if RubyProf.const_defined?(:MEMORY)
           
           # overridden by each implementation
-          def measure; 0; end
+          def measure; end
         end
 
         class Objects < Amount
           Mode = RubyProf::ALLOCATIONS if RubyProf.const_defined?(:ALLOCATIONS)
           
           # overridden by each implementation
-          def measure; 0; end
+          def measure; end
         end
 
         class GcRuns < Amount
           Mode = RubyProf::GC_RUNS if RubyProf.const_defined?(:GC_RUNS)
           
           # overridden by each implementation
-          def measure; 0; end
+          def measure; end
         end
 
         class GcTime < Time
           Mode = RubyProf::GC_TIME if RubyProf.const_defined?(:GC_TIME)
 
           # overridden by each implementation
-          def measure; 0; end
+          def measure; end
         end
       end
     end

activesupport/lib/active_support/testing/performance/ruby/mri.rb

@@ -24,8 +24,6 @@ module ActiveSupport
             end
           end
         end
-        
-        class Amount < Base; end
           
         class Objects < Amount
           # Ruby 1.8 + ruby-prof wrapper

railties/guides/source/performance_testing.textile

@@ -223,7 +223,7 @@ h6. Profiling
 |_.Rubinius   | yes       | no           | no       | no        | no     | no      | no      | no      |
 |_.JRuby      | yes       | no           | no       | no        | no     | no      | no      | no      |
 
-WARNING: Profiling under JRuby is currently unavailable because of a bug with rake and JRuby's +--profile.api+ option. You should resort exclusively to benchmarking.
+NOTE: To profile under JRuby you'll need to run +export JRUBY_OPTS="-Xlaunch.inproc=false --profile.api"+ *before* the performance tests.
 
 h4. Understanding the Output
 
@@ -309,8 +309,6 @@ h6. Output Availability
 |_.Rubinius | yes  | yes   | no   |
 |_.JRuby    | yes  | yes   | no   |
 
-WARNING: Again, profiling under JRuby is currently unavailable because of a bug with rake and JRuby's +--profile.api+ option.
-
 h4. Tuning Test Runs
 
 Test runs can be tuned by setting the +profile_options+ class variable on your test class.