diff --git a/Authors b/Authors
index afcc2bd7..4df82141 100644
--- a/Authors
+++ b/Authors
@@ -43,6 +43,7 @@ David Subiros <david.perez5@hp.com>
 Dean Troyer <dtroyer@gmail.com>
 Deepak Garg <deepak.garg@citrix.com>
 Derek Higgins <higginsd@gmail.com>
+Devdeep Singh <devdeep.singh@citrix.com>
 Devendra Modium <dmodium@isi.edu>
 Devin Carlen <devin.carlen@gmail.com>
 Donal Lafferty <donal.lafferty@citrix.com>
diff --git a/nova/flags.py b/nova/flags.py
index 6fc3100f..ea6176e9 100644
--- a/nova/flags.py
+++ b/nova/flags.py
@@ -445,6 +445,12 @@ global_opts = [
     cfg.ListOpt('isolated_hosts',
                 default=[],
                 help='Host reserved for specific images'),
+    cfg.BoolOpt('cache_images',
+                default=True,
+                help='Cache glance images locally'),
+    cfg.BoolOpt('use_cow_images',
+                default=True,
+                help='Whether to use cow images')
     ]
 
 FLAGS.register_opts(global_opts)
diff --git a/nova/tests/test_xenapi.py b/nova/tests/test_xenapi.py
index ec10defe..6fc7fdf7 100644
--- a/nova/tests/test_xenapi.py
+++ b/nova/tests/test_xenapi.py
@@ -399,7 +399,14 @@ class XenAPIVMTestCase(test.TestCase):
     def _check_vdis(self, start_list, end_list):
         for vdi_ref in end_list:
             if not vdi_ref in start_list:
-                self.fail('Found unexpected VDI:%s' % vdi_ref)
+                vdi_rec = xenapi_fake.get_record('VDI', vdi_ref)
+                # If the cache is turned on then the base disk will be
+                # there even after the cleanup
+                if 'other_config' in vdi_rec:
+                    if vdi_rec['other_config']['image-id'] is None:
+                        self.fail('Found unexpected VDI:%s' % vdi_ref)
+                else:
+                    self.fail('Found unexpected VDI:%s' % vdi_ref)
 
     def _test_spawn(self, image_ref, kernel_id, ramdisk_id,
                     instance_type_id="3", os_type="linux",
diff --git a/nova/tests/xenapi/stubs.py b/nova/tests/xenapi/stubs.py
index 2dfece00..27e2acd9 100644
--- a/nova/tests/xenapi/stubs.py
+++ b/nova/tests/xenapi/stubs.py
@@ -46,7 +46,7 @@ def stubout_instance_snapshot(stubs):
 
     def fake_wait_for_vhd_coalesce(*args):
         #TODO(sirp): Should we actually fake out the data here
-        return "fakeparent"
+        return "fakeparent", "fakebase"
 
     stubs.Set(vm_utils, '_wait_for_vhd_coalesce', fake_wait_for_vhd_coalesce)