diff --git a/ceilometer/compute/pollsters/util.py b/ceilometer/compute/pollsters/util.py
index 28adf655..1fd4f95f 100644
--- a/ceilometer/compute/pollsters/util.py
+++ b/ceilometer/compute/pollsters/util.py
@@ -13,7 +13,6 @@
 # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 # License for the specific language governing permissions and limitations
 # under the License.
-from oslo_utils import timeutils
 
 from ceilometer.compute import util as compute_util
 from ceilometer import sample
@@ -88,7 +87,6 @@ def make_sample_from_instance(instance, name, type, unit, volume,
         user_id=instance.user_id,
         project_id=instance.tenant_id,
         resource_id=resource_id or instance.id,
-        timestamp=timeutils.utcnow().isoformat(),
         resource_metadata=resource_metadata,
     )
 
diff --git a/ceilometer/energy/kwapi.py b/ceilometer/energy/kwapi.py
index 9a8cac48..9bb8caa8 100644
--- a/ceilometer/energy/kwapi.py
+++ b/ceilometer/energy/kwapi.py
@@ -12,8 +12,6 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-import datetime
-
 from keystoneauth1 import exceptions
 from oslo_config import cfg
 from oslo_log import log
@@ -104,8 +102,6 @@ class EnergyPollster(_Base):
                     user_id=None,
                     project_id=None,
                     resource_id=probe['id'],
-                    timestamp=datetime.datetime.fromtimestamp(
-                        probe['timestamp']).isoformat(),
                     resource_metadata={}
                 )
 
@@ -124,7 +120,5 @@ class PowerPollster(_Base):
                     user_id=None,
                     project_id=None,
                     resource_id=probe['id'],
-                    timestamp=datetime.datetime.fromtimestamp(
-                        probe['timestamp']).isoformat(),
                     resource_metadata={}
                 )
diff --git a/ceilometer/hardware/pollsters/util.py b/ceilometer/hardware/pollsters/util.py
index ac598aa2..5a68c658 100644
--- a/ceilometer/hardware/pollsters/util.py
+++ b/ceilometer/hardware/pollsters/util.py
@@ -20,7 +20,6 @@
 
 import copy
 
-from oslo_utils import timeutils
 from six.moves.urllib import parse as urlparse
 
 from ceilometer import sample
@@ -59,7 +58,6 @@ def make_sample_from_host(host_url, name, sample_type, unit, volume,
         user_id=user_id or extra.get('user_id'),
         project_id=project_id or extra.get('project_id'),
         resource_id=res_id,
-        timestamp=timeutils.utcnow().isoformat(),
         resource_metadata=resource_metadata,
         source='hardware',
     )
diff --git a/ceilometer/image/glance.py b/ceilometer/image/glance.py
index 3a76ad9b..e25aaedd 100644
--- a/ceilometer/image/glance.py
+++ b/ceilometer/image/glance.py
@@ -19,7 +19,6 @@ from __future__ import absolute_import
 
 import glanceclient
 from oslo_config import cfg
-from oslo_utils import timeutils
 
 from ceilometer.agent import plugin_base
 from ceilometer import keystone_client
@@ -110,7 +109,6 @@ class ImagePollster(_Base):
                     user_id=None,
                     project_id=image.owner,
                     resource_id=image.id,
-                    timestamp=timeutils.utcnow().isoformat(),
                     resource_metadata=self.extract_image_metadata(image),
                 )
 
@@ -127,6 +125,5 @@ class ImageSizePollster(_Base):
                     user_id=None,
                     project_id=image.owner,
                     resource_id=image.id,
-                    timestamp=timeutils.utcnow().isoformat(),
                     resource_metadata=self.extract_image_metadata(image),
                 )
diff --git a/ceilometer/ipmi/pollsters/node.py b/ceilometer/ipmi/pollsters/node.py
index 57cdcd3d..8540cc4c 100644
--- a/ceilometer/ipmi/pollsters/node.py
+++ b/ceilometer/ipmi/pollsters/node.py
@@ -16,7 +16,6 @@ import abc
 
 from oslo_config import cfg
 from oslo_log import log
-from oslo_utils import timeutils
 import six
 
 from ceilometer.agent import plugin_base
@@ -89,7 +88,6 @@ class _Base(plugin_base.PollsterBase):
                 user_id=None,
                 project_id=None,
                 resource_id=CONF.host,
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=metadata)
 
 
diff --git a/ceilometer/ipmi/pollsters/sensor.py b/ceilometer/ipmi/pollsters/sensor.py
index 01963965..249913ce 100644
--- a/ceilometer/ipmi/pollsters/sensor.py
+++ b/ceilometer/ipmi/pollsters/sensor.py
@@ -14,7 +14,6 @@
 
 from oslo_config import cfg
 from oslo_log import log
-from oslo_utils import timeutils
 
 from ceilometer.agent import plugin_base
 from ceilometer.i18n import _
@@ -112,7 +111,6 @@ class SensorPollster(plugin_base.PollsterBase):
                 user_id=None,
                 project_id=None,
                 resource_id=resource_id,
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=metadata)
 
 
diff --git a/ceilometer/network/floatingip.py b/ceilometer/network/floatingip.py
index 62a5101d..ce178704 100644
--- a/ceilometer/network/floatingip.py
+++ b/ceilometer/network/floatingip.py
@@ -18,7 +18,6 @@
 
 from oslo_config import cfg
 from oslo_log import log
-from oslo_utils import timeutils
 
 from ceilometer.i18n import _LW
 from ceilometer.network.services import base
@@ -59,6 +58,5 @@ class FloatingIPPollster(base.BaseServicesPollster):
                 user_id=fip.get('user_id'),
                 project_id=fip['tenant_id'],
                 resource_id=fip['id'],
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=self.extract_metadata(fip)
             )
diff --git a/ceilometer/network/services/fwaas.py b/ceilometer/network/services/fwaas.py
index 72517698..7b827613 100644
--- a/ceilometer/network/services/fwaas.py
+++ b/ceilometer/network/services/fwaas.py
@@ -14,7 +14,6 @@
 # under the License.
 
 from oslo_log import log
-from oslo_utils import timeutils
 
 from ceilometer.i18n import _
 from ceilometer.network.services import base
@@ -58,7 +57,6 @@ class FirewallPollster(base.BaseServicesPollster):
                 user_id=None,
                 project_id=fw['tenant_id'],
                 resource_id=fw['id'],
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=self.extract_metadata(fw)
             )
 
@@ -92,6 +90,5 @@ class FirewallPolicyPollster(base.BaseServicesPollster):
                 user_id=None,
                 project_id=fw['tenant_id'],
                 resource_id=fw['id'],
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=self.extract_metadata(fw)
             )
diff --git a/ceilometer/network/services/lbaas.py b/ceilometer/network/services/lbaas.py
index a775c7fe..5f33d22c 100644
--- a/ceilometer/network/services/lbaas.py
+++ b/ceilometer/network/services/lbaas.py
@@ -18,7 +18,6 @@ import collections
 
 from oslo_config import cfg
 from oslo_log import log
-from oslo_utils import timeutils
 import six
 
 from ceilometer.i18n import _
@@ -98,7 +97,6 @@ class LBPoolPollster(BaseLBPollster):
                 user_id=None,
                 project_id=pool['tenant_id'],
                 resource_id=pool['id'],
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=self.extract_metadata(pool)
             )
 
@@ -146,7 +144,6 @@ class LBVipPollster(base.BaseServicesPollster):
                 user_id=None,
                 project_id=vip['tenant_id'],
                 resource_id=vip['id'],
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=self.extract_metadata(vip)
             )
 
@@ -186,7 +183,6 @@ class LBMemberPollster(BaseLBPollster):
                 user_id=None,
                 project_id=member['tenant_id'],
                 resource_id=member['id'],
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=self.extract_metadata(member)
             )
 
@@ -217,7 +213,6 @@ class LBHealthMonitorPollster(base.BaseServicesPollster):
                 user_id=None,
                 project_id=probe['tenant_id'],
                 resource_id=probe['id'],
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=self.extract_metadata(probe)
             )
 
@@ -248,7 +243,6 @@ class _LBStatsPollster(base.BaseServicesPollster):
             user_id=None,
             project_id=pool['tenant_id'],
             resource_id=pool['id'],
-            timestamp=timeutils.utcnow().isoformat(),
             resource_metadata=resource_metadata,
         )
 
@@ -377,7 +371,6 @@ def make_sample_from_pool(pool, name, type, unit, volume,
         user_id=None,
         project_id=pool['tenant_id'],
         resource_id=pool['id'],
-        timestamp=timeutils.utcnow().isoformat(),
         resource_metadata=resource_metadata,
     )
 
@@ -423,7 +416,6 @@ class LBListenerPollster(BaseLBPollster):
                 user_id=None,
                 project_id=listener['tenant_id'],
                 resource_id=listener['id'],
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=self.extract_metadata(listener)
             )
 
@@ -468,6 +460,5 @@ class LBLoadBalancerPollster(BaseLBPollster):
                 user_id=None,
                 project_id=loadbalancer['tenant_id'],
                 resource_id=loadbalancer['id'],
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=self.extract_metadata(loadbalancer)
             )
diff --git a/ceilometer/network/services/vpnaas.py b/ceilometer/network/services/vpnaas.py
index 9e423c99..948613d4 100644
--- a/ceilometer/network/services/vpnaas.py
+++ b/ceilometer/network/services/vpnaas.py
@@ -14,7 +14,6 @@
 # under the License.
 
 from oslo_log import log
-from oslo_utils import timeutils
 
 from ceilometer.i18n import _
 from ceilometer.network.services import base
@@ -59,7 +58,6 @@ class VPNServicesPollster(base.BaseServicesPollster):
                 user_id=None,
                 project_id=vpn['tenant_id'],
                 resource_id=vpn['id'],
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=self.extract_metadata(vpn)
             )
 
@@ -102,6 +100,5 @@ class IPSecConnectionsPollster(base.BaseServicesPollster):
                 user_id=None,
                 project_id=conn['tenant_id'],
                 resource_id=conn['id'],
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=self.extract_metadata(conn)
             )
diff --git a/ceilometer/network/statistics/__init__.py b/ceilometer/network/statistics/__init__.py
index ce692d2b..f45ed710 100644
--- a/ceilometer/network/statistics/__init__.py
+++ b/ceilometer/network/statistics/__init__.py
@@ -86,7 +86,7 @@ class _Base(plugin_base.PollsterBase):
                 if not isinstance(data, list):
                     data = [data]
                 for (volume, resource_id,
-                     resource_metadata, timestamp) in data:
+                     resource_metadata) in data:
 
                     yield sample.Sample(
                         name=self.meter_name,
@@ -96,6 +96,5 @@ class _Base(plugin_base.PollsterBase):
                         user_id=None,
                         project_id=None,
                         resource_id=resource_id,
-                        timestamp=timestamp,
                         resource_metadata=resource_metadata
                     )
diff --git a/ceilometer/network/statistics/opencontrail/driver.py b/ceilometer/network/statistics/opencontrail/driver.py
index f511f3c1..5cb32dee 100644
--- a/ceilometer/network/statistics/opencontrail/driver.py
+++ b/ceilometer/network/statistics/opencontrail/driver.py
@@ -14,7 +14,6 @@
 
 import re
 
-from oslo_utils import timeutils
 from six.moves.urllib import parse as urlparse
 
 from ceilometer.network.statistics import driver
@@ -104,7 +103,6 @@ class OpencontrailDriver(driver.Driver):
         fqdn_uuid = params.get('fqdn_uuid', ['*'])[0]
         virtual_network = params.get('virtual_network', [None])[0]
 
-        timestamp = timeutils.utcnow().isoformat()
         statistics = data['o_client'].networks.get_vm_statistics(fqdn_uuid)
         if not statistics:
             return
@@ -113,7 +111,7 @@ class OpencontrailDriver(driver.Driver):
             for sample in iter(extractor, value, ports_map,
                                resource, virtual_network):
                 if sample is not None:
-                    yield sample + (timestamp, )
+                    yield sample
 
     def _get_iter(self, meter_name):
         if meter_name.startswith('switch.port'):
diff --git a/ceilometer/network/statistics/opendaylight/driver.py b/ceilometer/network/statistics/opendaylight/driver.py
index 195b697d..bc78dbe5 100644
--- a/ceilometer/network/statistics/opendaylight/driver.py
+++ b/ceilometer/network/statistics/opendaylight/driver.py
@@ -14,7 +14,6 @@
 # under the License.
 
 from oslo_log import log
-from oslo_utils import timeutils
 import six
 from six import moves
 from six.moves.urllib import parse as urlparse
@@ -161,9 +160,6 @@ class OpenDayLightDriver(driver.Driver):
                     cs.host_tracker.get_active_hosts(container_name))
                 container_data['inactive_hosts'] = (
                     cs.host_tracker.get_inactive_hosts(container_name))
-
-                container_data['timestamp'] = timeutils.utcnow().isoformat()
-
                 data[container_name] = container_data
             except Exception:
                 LOG.exception(_('Request failed to connect to OpenDaylight'
@@ -199,7 +195,6 @@ class OpenDayLightDriver(driver.Driver):
 
         samples = []
         for name, value in six.iteritems(data):
-            timestamp = value['timestamp']
             for sample in iter(extractor, value):
                 if sample is not None:
                     # set controller name and container name
@@ -207,7 +202,7 @@ class OpenDayLightDriver(driver.Driver):
                     sample[2]['controller'] = 'OpenDaylight'
                     sample[2]['container'] = name
 
-                    samples.append(sample + (timestamp, ))
+                    samples.append(sample)
 
         return samples
 
diff --git a/ceilometer/objectstore/rgw.py b/ceilometer/objectstore/rgw.py
index e3ef290c..581df4c2 100644
--- a/ceilometer/objectstore/rgw.py
+++ b/ceilometer/objectstore/rgw.py
@@ -18,7 +18,6 @@
 from keystoneauth1 import exceptions
 from oslo_config import cfg
 from oslo_log import log
-from oslo_utils import timeutils
 import six.moves.urllib.parse as urlparse
 
 from ceilometer.agent import plugin_base
@@ -117,7 +116,6 @@ class ContainersObjectsPollster(_Base):
                     user_id=None,
                     project_id=tenant,
                     resource_id=tenant + '/' + it.name,
-                    timestamp=timeutils.utcnow().isoformat(),
                     resource_metadata=None,
                 )
 
@@ -137,7 +135,6 @@ class ContainersSizePollster(_Base):
                         user_id=None,
                         project_id=tenant,
                         resource_id=tenant + '/' + it.name,
-                        timestamp=timeutils.utcnow().isoformat(),
                         resource_metadata=None,
                     )
 
@@ -156,7 +153,6 @@ class ObjectsSizePollster(_Base):
                 user_id=None,
                 project_id=tenant,
                 resource_id=tenant,
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=None,
                 )
 
@@ -175,7 +171,6 @@ class ObjectsPollster(_Base):
                 user_id=None,
                 project_id=tenant,
                 resource_id=tenant,
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=None,
                 )
 
@@ -192,7 +187,6 @@ class ObjectsContainersPollster(_Base):
                 user_id=None,
                 project_id=tenant,
                 resource_id=tenant,
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=None,
                 )
 
@@ -212,6 +206,5 @@ class UsagePollster(_Base):
                 user_id=None,
                 project_id=tenant,
                 resource_id=tenant,
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=None,
                 )
diff --git a/ceilometer/objectstore/swift.py b/ceilometer/objectstore/swift.py
index ebd4806b..d57ff68b 100644
--- a/ceilometer/objectstore/swift.py
+++ b/ceilometer/objectstore/swift.py
@@ -20,7 +20,6 @@ from __future__ import absolute_import
 from keystoneauth1 import exceptions
 from oslo_config import cfg
 from oslo_log import log
-from oslo_utils import timeutils
 import six.moves.urllib.parse as urlparse
 from swiftclient import client as swift
 
@@ -117,7 +116,6 @@ class ObjectsPollster(_Base):
                 user_id=None,
                 project_id=tenant,
                 resource_id=tenant,
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=None,
             )
 
@@ -136,7 +134,6 @@ class ObjectsSizePollster(_Base):
                 user_id=None,
                 project_id=tenant,
                 resource_id=tenant,
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=None,
             )
 
@@ -155,7 +152,6 @@ class ObjectsContainersPollster(_Base):
                 user_id=None,
                 project_id=tenant,
                 resource_id=tenant,
-                timestamp=timeutils.utcnow().isoformat(),
                 resource_metadata=None,
             )
 
@@ -179,7 +175,6 @@ class ContainersObjectsPollster(_Base):
                     user_id=None,
                     project_id=tenant,
                     resource_id=tenant + '/' + container['name'],
-                    timestamp=timeutils.utcnow().isoformat(),
                     resource_metadata=None,
                 )
 
@@ -203,6 +198,5 @@ class ContainersSizePollster(_Base):
                     user_id=None,
                     project_id=tenant,
                     resource_id=tenant + '/' + container['name'],
-                    timestamp=timeutils.utcnow().isoformat(),
                     resource_metadata=None,
                 )
diff --git a/ceilometer/tests/unit/energy/test_kwapi.py b/ceilometer/tests/unit/energy/test_kwapi.py
index d8afae4f..eaf9dc0c 100644
--- a/ceilometer/tests/unit/energy/test_kwapi.py
+++ b/ceilometer/tests/unit/energy/test_kwapi.py
@@ -12,8 +12,6 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-import datetime
-
 from keystoneauth1 import exceptions
 import mock
 from oslotest import base
@@ -107,10 +105,6 @@ class TestEnergyPollster(_BaseTestCase):
         samples_by_name = dict((s.resource_id, s) for s in samples)
         for name, probe in PROBE_DICT['probes'].items():
             sample = samples_by_name[name]
-            expected = datetime.datetime.fromtimestamp(
-                probe['timestamp']
-            ).isoformat()
-            self.assertEqual(expected, sample.timestamp)
             self.assertEqual(probe[self.unit], sample.volume)
 
 
diff --git a/ceilometer/tests/unit/network/statistics/opencontrail/test_driver.py b/ceilometer/tests/unit/network/statistics/opencontrail/test_driver.py
index b3df42ed..c308f446 100644
--- a/ceilometer/tests/unit/network/statistics/opencontrail/test_driver.py
+++ b/ceilometer/tests/unit/network/statistics/opencontrail/test_driver.py
@@ -135,8 +135,7 @@ class TestOpencontrailDriver(base.BaseTestCase):
                       'network_id': '298a3088-a446-4d5a-bad8-f92ecacd786b',
                       'project': 'demo',
                       'project_id': '89271fa581ab4380bf172f868c3615f9',
-                      'resource': 'if_stats_list'},
-                     mock.ANY),
+                      'resource': 'if_stats_list'},),
                     (13,
                      '96d49cc3-4e01-40ce-9cac-c0e32642a442',
                      {'device_owner_id':
@@ -145,8 +144,7 @@ class TestOpencontrailDriver(base.BaseTestCase):
                       'network_id': '298a3088-a446-4d5a-bad8-f92ecacd786b',
                       'project': 'demo',
                       'project_id': '89271fa581ab4380bf172f868c3615f9',
-                      'resource': 'if_stats_list'},
-                     mock.ANY)]
+                      'resource': 'if_stats_list'},)]
         self._test_meter('switch.port.receive.packets', expected,
                          self.fake_port_stats_with_node())
 
@@ -159,8 +157,7 @@ class TestOpencontrailDriver(base.BaseTestCase):
                       'network_id': '298a3088-a446-4d5a-bad8-f92ecacd786b',
                       'project': 'demo',
                       'project_id': '89271fa581ab4380bf172f868c3615f9',
-                      'resource': 'if_stats_list'},
-                     mock.ANY)]
+                      'resource': 'if_stats_list'},)]
         self._test_meter('switch.port.receive.packets', expected)
 
     def test_switch_port_transmit_packets(self):
@@ -172,8 +169,7 @@ class TestOpencontrailDriver(base.BaseTestCase):
                       'network_id': '298a3088-a446-4d5a-bad8-f92ecacd786b',
                       'project': 'demo',
                       'project_id': '89271fa581ab4380bf172f868c3615f9',
-                      'resource': 'if_stats_list'},
-                     mock.ANY)]
+                      'resource': 'if_stats_list'},)]
         self._test_meter('switch.port.transmit.packets', expected)
 
     def test_switch_port_receive_bytes(self):
@@ -185,8 +181,7 @@ class TestOpencontrailDriver(base.BaseTestCase):
                       'network_id': '298a3088-a446-4d5a-bad8-f92ecacd786b',
                       'project': 'demo',
                       'project_id': '89271fa581ab4380bf172f868c3615f9',
-                      'resource': 'if_stats_list'},
-                     mock.ANY)]
+                      'resource': 'if_stats_list'},)]
         self._test_meter('switch.port.receive.bytes', expected)
 
     def test_switch_port_transmit_bytes(self):
@@ -198,8 +193,7 @@ class TestOpencontrailDriver(base.BaseTestCase):
                       'network_id': '298a3088-a446-4d5a-bad8-f92ecacd786b',
                       'project': 'demo',
                       'project_id': '89271fa581ab4380bf172f868c3615f9',
-                      'resource': 'if_stats_list'},
-                     mock.ANY)]
+                      'resource': 'if_stats_list'},)]
         self._test_meter('switch.port.transmit.bytes', expected)
 
     def test_switch_port_receive_packets_fip(self):
@@ -212,8 +206,7 @@ class TestOpencontrailDriver(base.BaseTestCase):
                       'network_id': '298a3088-a446-4d5a-bad8-f92ecacd786b',
                       'project': 'demo',
                       'project_id': '89271fa581ab4380bf172f868c3615f9',
-                      'resource': 'fip_stats_list'},
-                     mock.ANY)]
+                      'resource': 'fip_stats_list'},)]
         self._test_meter('switch.port.receive.packets', expected)
 
     def test_switch_port_transmit_packets_fip(self):
@@ -226,8 +219,7 @@ class TestOpencontrailDriver(base.BaseTestCase):
                       'network_id': '298a3088-a446-4d5a-bad8-f92ecacd786b',
                       'project': 'demo',
                       'project_id': '89271fa581ab4380bf172f868c3615f9',
-                      'resource': 'fip_stats_list'},
-                     mock.ANY)]
+                      'resource': 'fip_stats_list'},)]
         self._test_meter('switch.port.transmit.packets', expected)
 
     def test_switch_port_receive_bytes_fip(self):
@@ -240,8 +232,7 @@ class TestOpencontrailDriver(base.BaseTestCase):
                       'network_id': '298a3088-a446-4d5a-bad8-f92ecacd786b',
                       'project': 'demo',
                       'project_id': '89271fa581ab4380bf172f868c3615f9',
-                      'resource': 'fip_stats_list'},
-                     mock.ANY)]
+                      'resource': 'fip_stats_list'},)]
         self._test_meter('switch.port.receive.bytes', expected)
 
     def test_switch_port_transmit_bytes_fip(self):
@@ -254,8 +245,7 @@ class TestOpencontrailDriver(base.BaseTestCase):
                       'network_id': '298a3088-a446-4d5a-bad8-f92ecacd786b',
                       'project': 'demo',
                       'project_id': '89271fa581ab4380bf172f868c3615f9',
-                      'resource': 'fip_stats_list'},
-                     mock.ANY)]
+                      'resource': 'fip_stats_list'},)]
         self._test_meter('switch.port.transmit.bytes', expected)
 
     def test_switch_port_transmit_bytes_non_existing_network(self):
diff --git a/ceilometer/tests/unit/network/statistics/opendaylight/test_driver.py b/ceilometer/tests/unit/network/statistics/opendaylight/test_driver.py
index fd64c098..891b3a1d 100644
--- a/ceilometer/tests/unit/network/statistics/opendaylight/test_driver.py
+++ b/ceilometer/tests/unit/network/statistics/opendaylight/test_driver.py
@@ -122,7 +122,6 @@ class _Base(base.BaseTestCase):
             self.assertEqual(expected[0], sample[0])  # check volume
             self.assertEqual(expected[1], sample[1])  # check resource id
             self.assertEqual(expected[2], sample[2])  # check resource metadata
-            self.assertIsNotNone(sample[3])  # timestamp
 
 
 class TestOpenDayLightDriverSpecial(_Base):
diff --git a/ceilometer/tests/unit/network/statistics/test_statistics.py b/ceilometer/tests/unit/network/statistics/test_statistics.py
index c1abea01..5afdd790 100644
--- a/ceilometer/tests/unit/network/statistics/test_statistics.py
+++ b/ceilometer/tests/unit/network/statistics/test_statistics.py
@@ -105,75 +105,65 @@ class TestBaseGetSamples(base.BaseTestCase):
 
         return [v for v in self.pollster.get_samples(self, {}, resources)]
 
-    def _assert_sample(self, s, volume, resource_id, resource_metadata,
-                       timestamp):
-            self.assertEqual('foo', s.name)
-            self.assertEqual(sample.TYPE_CUMULATIVE, s.type)
-            self.assertEqual('bar', s.unit)
-            self.assertEqual(volume, s.volume)
-            self.assertIsNone(s.user_id)
-            self.assertIsNone(s.project_id)
-            self.assertEqual(resource_id, s.resource_id)
-            self.assertEqual(timestamp, s.timestamp)
-            self.assertEqual(resource_metadata, s.resource_metadata)
+    def _assert_sample(self, s, volume, resource_id, resource_metadata):
+        self.assertEqual('foo', s.name)
+        self.assertEqual(sample.TYPE_CUMULATIVE, s.type)
+        self.assertEqual('bar', s.unit)
+        self.assertEqual(volume, s.volume)
+        self.assertIsNone(s.user_id)
+        self.assertIsNone(s.project_id)
+        self.assertEqual(resource_id, s.resource_id)
+        self.assertEqual(resource_metadata, s.resource_metadata)
 
     def test_get_samples_one_driver_one_resource(self):
-        times = self._make_timestamps(2)
-        fake_driver = self._make_fake_driver((1, 'a', {'spam': 'egg'},
-                                              times[0]),
-                                             (2, 'b', None, times[1]))
+        fake_driver = self._make_fake_driver((1, 'a', {'spam': 'egg'},),
+                                             (2, 'b', None))
 
         self._setup_ext_mgr(http=fake_driver())
 
         samples = self._get_samples('http://foo')
 
         self.assertEqual(1, len(samples))
-        self._assert_sample(samples[0], 1, 'a', {'spam': 'egg'}, times[0])
+        self._assert_sample(samples[0], 1, 'a', {'spam': 'egg'})
 
     def test_get_samples_one_driver_two_resource(self):
-        times = self._make_timestamps(3)
-        fake_driver = self._make_fake_driver((1, 'a', {'spam': 'egg'},
-                                              times[0]),
-                                             (2, 'b', None, times[1]),
-                                             (3, 'c', None, times[2]))
+        fake_driver = self._make_fake_driver((1, 'a', {'spam': 'egg'},),
+                                             (2, 'b', None),
+                                             (3, 'c', None))
 
         self._setup_ext_mgr(http=fake_driver())
 
         samples = self._get_samples('http://foo', 'http://bar')
 
         self.assertEqual(2, len(samples))
-        self._assert_sample(samples[0], 1, 'a', {'spam': 'egg'}, times[0])
-        self._assert_sample(samples[1], 2, 'b', {}, times[1])
+        self._assert_sample(samples[0], 1, 'a', {'spam': 'egg'})
+        self._assert_sample(samples[1], 2, 'b', {})
 
     def test_get_samples_two_driver_one_resource(self):
-        times = self._make_timestamps(4)
-        fake_driver1 = self._make_fake_driver((1, 'a', {'spam': 'egg'},
-                                               times[0]),
-                                              (2, 'b', None), times[1])
+        fake_driver1 = self._make_fake_driver((1, 'a', {'spam': 'egg'},),
+                                              (2, 'b', None))
 
-        fake_driver2 = self._make_fake_driver((11, 'A', None, times[2]),
-                                              (12, 'B', None, times[3]))
+        fake_driver2 = self._make_fake_driver((11, 'A', None),
+                                              (12, 'B', None))
 
         self._setup_ext_mgr(http=fake_driver1(), https=fake_driver2())
 
         samples = self._get_samples('http://foo')
 
         self.assertEqual(1, len(samples))
-        self._assert_sample(samples[0], 1, 'a', {'spam': 'egg'}, times[0])
+        self._assert_sample(samples[0], 1, 'a', {'spam': 'egg'})
 
     def test_get_samples_multi_samples(self):
-        times = self._make_timestamps(2)
-        fake_driver = self._make_fake_driver([(1, 'a', {'spam': 'egg'},
-                                               times[0]),
-                                              (2, 'b', None, times[1])])
+        fake_driver = self._make_fake_driver([(1, 'a', {'spam': 'egg'},),
+                                              (2, 'b', None)])
 
         self._setup_ext_mgr(http=fake_driver())
 
         samples = self._get_samples('http://foo')
 
         self.assertEqual(2, len(samples))
-        self._assert_sample(samples[0], 1, 'a', {'spam': 'egg'}, times[0])
-        self._assert_sample(samples[1], 2, 'b', {}, times[1])
+        self._assert_sample(samples[0], 1, 'a', {'spam': 'egg'})
+        self._assert_sample(samples[1], 2, 'b', {})
 
     def test_get_samples_return_none(self):
         fake_driver = self._make_fake_driver(None)
diff --git a/releasenotes/notes/unify-timestamp-of-polled-data-fbfcff43cd2d04bc.yaml b/releasenotes/notes/unify-timestamp-of-polled-data-fbfcff43cd2d04bc.yaml
new file mode 100644
index 00000000..c3977fb9
--- /dev/null
+++ b/releasenotes/notes/unify-timestamp-of-polled-data-fbfcff43cd2d04bc.yaml
@@ -0,0 +1,7 @@
+---
+fixes:
+  - >
+    [`bug 1491509 <https://bugs.launchpad.net/ceilometer/+bug/1491509>`_]
+    Patch to unify timestamp in samples polled by pollsters. Set the time
+    point polling starts as timestamp of samples, and drop timetamping in
+    pollsters.