diff --git a/ChangeLog b/ChangeLog
index 0f0f1838cc..bfb3becc51 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Sat Aug 25 00:49:44 2007  Koichi Sasada  <ko1@atdot.net>
+
+	* benchmark/bm_loop_generator.rb: added.
+
 Sat Aug 25 00:22:31 2007  Koichi Sasada  <ko1@atdot.net>
 
 	* prelude.rb: added.  run this script on startup.
diff --git a/benchmark/bm_loop_generator.rb b/benchmark/bm_loop_generator.rb
new file mode 100644
index 0000000000..e9bf9afc24
--- /dev/null
+++ b/benchmark/bm_loop_generator.rb
@@ -0,0 +1,14 @@
+max = 600000
+
+if defined? Fiber
+  gen = (1..max).each
+  loop do
+    gen.next
+  end
+else
+  require 'generator'
+  gen = Generator.new((0..max))
+  while gen.next?
+    gen.next
+  end
+end