don't send a getmore immediately after every query

lib/mongo/cursor.rb

@@ -206,8 +206,9 @@ module XGen
         end
 
         def refill_via_get_more
-          send_query_if_needed
+          if send_query_if_needed or @cursor_id == 0
-          return if @cursor_id == 0
+            return
+          end
           @db._synchronize {
             @db.send_to_db(GetMoreMessage.new(@admin ? 'admin' : @db.name, @collection.name, @cursor_id))
             read_all
@@ -227,12 +228,15 @@ module XGen
 
         def send_query_if_needed
           # Run query first time we request an object from the wire
-          unless @query_run
+          if @query_run
+            false
+          else
             @db._synchronize {
               @db.send_query_message(QueryMessage.new(@admin ? 'admin' : @db.name, @collection.name, @query))
               @query_run = true
               read_all
             }
+            true
           end
         end
 

test/test_cursor.rb

@@ -145,4 +145,61 @@ class CursorTest < Test::Unit::TestCase
     end
   end
 
+  def test_kill_cursors
+    @@coll.drop
+
+    client_cursors = @@db.db_command("cursorInfo" => 1)["clientCursors_size"]
+    by_location = @@db.db_command("cursorInfo" => 1)["byLocation_size"]
+
+    10000.times do |i|
+      @@coll.insert("i" => i)
+    end
+
+    assert_equal(client_cursors,
+                 @@db.db_command("cursorInfo" => 1)["clientCursors_size"])
+    assert_equal(by_location,
+                 @@db.db_command("cursorInfo" => 1)["byLocation_size"])
+
+    10.times do |i|
+      @@coll.find_one()
+    end
+
+    assert_equal(client_cursors,
+                 @@db.db_command("cursorInfo" => 1)["clientCursors_size"])
+    assert_equal(by_location,
+                 @@db.db_command("cursorInfo" => 1)["byLocation_size"])
+
+    10.times do |i|
+      a = @@coll.find()
+      a.next_object()
+      a.close()
+    end
+
+    assert_equal(client_cursors,
+                 @@db.db_command("cursorInfo" => 1)["clientCursors_size"])
+    assert_equal(by_location,
+                 @@db.db_command("cursorInfo" => 1)["byLocation_size"])
+
+    a = @@coll.find()
+    a.next_object()
+
+    assert_not_equal(client_cursors,
+                     @@db.db_command("cursorInfo" => 1)["clientCursors_size"])
+    assert_not_equal(by_location,
+                     @@db.db_command("cursorInfo" => 1)["byLocation_size"])
+
+    a.close()
+
+    assert_equal(client_cursors,
+                 @@db.db_command("cursorInfo" => 1)["clientCursors_size"])
+    assert_equal(by_location,
+                 @@db.db_command("cursorInfo" => 1)["byLocation_size"])
+
+    a = @@coll.find({}, :limit => 10).next_object()
+
+    assert_equal(client_cursors,
+                 @@db.db_command("cursorInfo" => 1)["clientCursors_size"])
+    assert_equal(by_location,
+                 @@db.db_command("cursorInfo" => 1)["byLocation_size"])
+  end
 end