connection pool starts the reaper

activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb

@@ -107,6 +107,7 @@ def initialize(spec)
 
         @timeout = spec.config[:wait_timeout] || 5
         @reaper  = Reaper.new self, spec.config[:reaping_frequency]
+        @reaper.start
 
         # default max pool size to 5
         @size = (spec.config[:pool] && spec.config[:pool].to_i) || 5

activerecord/test/cases/reaper_test.rb

@@ -52,6 +52,22 @@ def test_reaping_frequency_configuration
         pool = ConnectionPool.new spec
         assert_equal 100, pool.reaper.frequency
       end
+
+      def test_connection_pool_starts_reaper
+        spec = ActiveRecord::Base.connection_pool.spec.dup
+        spec.config[:reaping_frequency] = 0.0001
+
+        pool = ConnectionPool.new spec
+        pool.timeout = 0
+
+        conn = pool.checkout
+        count = pool.connections.length
+
+        conn.extend(Module.new { def active?; false; end; })
+
+        sleep 0.0002
+        assert_equal(count - 1, pool.connections.length)
+      end
     end
   end
 end