diff --git a/Gemfile b/Gemfile
index 2c12bbe..79f6d80 100644
--- a/Gemfile
+++ b/Gemfile
@@ -17,6 +17,7 @@ group :development, :test do
   gem "ci_reporter"
   gem "ruby-prof" unless RUBY_PLATFORM =~ /java/
   gem "perftools.rb" unless RUBY_PLATFORM =~ /java/
+  gem "rake-compiler"
 
   # Java
   platforms :jruby do
diff --git a/Rakefile b/Rakefile
index cf75565..547474d 100644
--- a/Rakefile
+++ b/Rakefile
@@ -7,6 +7,8 @@ end
 require 'fileutils'
 require 'rake/testtask'
 require 'rake'
+require 'rake/extensiontask'
+require 'rake/javaextensiontask'
 
 begin
   require 'git'
@@ -20,6 +22,14 @@ end
 
 ENV['TEST_MODE'] = 'TRUE'
 
+Rake::ExtensionTask.new('cbson') do |ext|
+  ext.lib_dir = "lib/bson_ext"
+end
+
+#Rake::JavaExtensionTask.new('jbson') do |ext| # not yet functional
+#  ext.ext_dir = 'ext/src/org/jbson'
+#end
+
 task :java do
   Rake::Task['build:java'].invoke
   Rake::Task['test:ruby'].invoke
diff --git a/bench/exp_series.html b/bench/exp_series.html
index 72675e1..a2b9fb0 100644
--- a/bench/exp_series.html
+++ b/bench/exp_series.html
@@ -25,7 +25,7 @@
     <h1>Exp Series Performance Tests</h1>
     x-axis is power of 2, log base 2 of size<br>
     y-axis is operations per user-time CPU-second<br>
-    Note that this is not operations per real-time second that includes DB real-time<br>
+    Note that this is not operations per real-time second that include DB real-time<br>
     <div id="placeholder"></div>
 
 <script type="text/javascript">
@@ -136,10 +136,8 @@ $(function () {
         ]
     ];
     $.each(graph, function(i, e){
-        var title = e[0];
-        var xMax = e[1];
-        var labelSpec = e[2];
-        var plotSpecs = e[3];
+        var title, xMax, labelSpec, plotSpecs;
+        title = e[0]; xMax = e[1]; labelSpec = e[2]; plotSpecs = e[3]; //[title, xMax, labelSpec, plotSpecs] = e;
         var series = flotSeries(expSeries, xMax, labelSpec, plotSpecs);
         doPlot(title, series);
     });
diff --git a/bench/profile_array.rb b/bench/profile_array.rb
index c3a5c5f..3f20565 100644
--- a/bench/profile_array.rb
+++ b/bench/profile_array.rb
@@ -16,7 +16,6 @@ def set_mongo_driver_mode(mode)
 end
 
 $mode = ARGV[0].to_sym if ARGV[0]
-#p (ARGV[0] && ARGV[0].to_sym || :c)
 set_mongo_driver_mode($mode || :c)
 
 require 'rubygems'
@@ -40,6 +39,16 @@ def insert(coll, h)
   coll.insert(h) # note that insert stores :_id in h and subsequent inserts are updates
 end
 
+def benchmark(iterations)
+  btms = Benchmark.measure do
+    (0...iterations).each do
+      yield
+    end
+  end
+  utime = btms.utime
+  p ({'ops' => (iterations.to_f / utime.to_f).round(1)})
+end
+
 def ruby_prof(iterations)
   RubyProf.start
   puts Benchmark.measure {
@@ -57,7 +66,7 @@ def ruby_prof(iterations)
 end
 
 def perftools(iterations)
-  profile_file_name = "/tmp/profile_array.perftools"
+  profile_file_name = '/tmp/profile_array.perftools'
   PerfTools::CpuProfiler.start(profile_file_name) do
     iterations.times { yield }
   end
@@ -71,12 +80,17 @@ db  = conn['benchmark']
 coll = db['profile']
 
 coll.remove
-puts "coll.count: #{coll.count}"
+#puts "coll.count: #{coll.count}"
 
-n, doc = array_size_fixnum(2, 6)
-ruby_prof(1000) { insert(coll, doc) }
+base = 2
+power = 6
+n, doc = array_size_fixnum(base, power)
+p ({'generator' => 'array_size_fixnum', 'operation' => 'insert',  'base' => base, 'power' => power})
+
+benchmark(10000) { insert(coll, doc)} # valgrind --tool=callgrind ruby bench/profile_array.rb; callgrind_annotate ...
+#ruby_prof(1000) { insert(coll, doc) }
 #perftools(10000) { insert(coll, doc) }
 
-puts "coll.count: #{coll.count}"
+#puts "coll.count: #{coll.count}"
 coll.remove