diff --git a/watcher/common/nova_helper.py b/watcher/common/nova_helper.py index 6c0a3c8f7..7f8665ccf 100644 --- a/watcher/common/nova_helper.py +++ b/watcher/common/nova_helper.py @@ -82,19 +82,25 @@ class NovaHelper(object): LOG.exception(exc) raise exception.ComputeNodeNotFound(name=node_hostname) - def get_instance_list(self, filters=None): + def get_instance_list(self, filters=None, limit=-1): """List servers for all tenants with details. This always gets servers with the all_tenants=True filter. - :param filters: dict of additional filters + :param filters: dict of additional filters (optional). + :param limit: Maximum number of servers to return (optional). + If limit == -1, all servers will be returned, + note that limit == -1 will have a performance + penalty. For details, please see: + https://bugs.launchpad.net/watcher/+bug/1834679 :returns: list of novaclient Server objects """ search_opts = {'all_tenants': True} if filters: search_opts.update(filters) + # TODO(chenker) Add marker param to list Server objects. return self.nova.servers.list(search_opts=search_opts, - limit=-1) + limit=limit) def get_instance_by_uuid(self, instance_uuid): return [instance for instance in diff --git a/watcher/decision_engine/model/collector/nova.py b/watcher/decision_engine/model/collector/nova.py index 97c21dbac..e9d965c23 100644 --- a/watcher/decision_engine/model/collector/nova.py +++ b/watcher/decision_engine/model/collector/nova.py @@ -327,8 +327,18 @@ class ModelBuilder(object): return host = node.service["host"] compute_node = self.model.get_node_by_uuid(host) + filters = {'host': host} + limit = len(instances) if len(instances) <= 1000 else -1 # Get all servers on this compute host. - instances = self.nova_helper.get_instance_list({'host': host}) + # Note that the advantage of passing the limit parameter is + # that it can speed up the call time of novaclient. 1000 is + # the default maximum number of return servers provided by + # compute API. If we need to request more than 1000 servers, + # we can set limit=-1. For details, please see: + # https://bugs.launchpad.net/watcher/+bug/1834679 + instances = self.nova_helper.get_instance_list( + filters=filters, + limit=limit) for inst in instances: # Add Node instance = self._build_instance_node(inst) diff --git a/watcher/tests/decision_engine/cluster/test_nova_cdmc.py b/watcher/tests/decision_engine/cluster/test_nova_cdmc.py index 1e9607f65..6d7de91d0 100644 --- a/watcher/tests/decision_engine/cluster/test_nova_cdmc.py +++ b/watcher/tests/decision_engine/cluster/test_nova_cdmc.py @@ -115,4 +115,26 @@ class TestNovaClusterDataModelCollector(base.TestCase): m_nova_helper.get_compute_node_by_name.assert_called_once_with( minimal_node['hypervisor_hostname'], servers=True, detailed=True) m_nova_helper.get_instance_list.assert_called_once_with( - {'host': fake_compute_node.service['host']}) + filters={'host': fake_compute_node.service['host']}, limit=1) + + +class TestModelBuilder(base.TestCase): + + @mock.patch.object(nova_helper, 'NovaHelper', mock.MagicMock()) + def test_add_instance_node(self): + model_builder = nova.ModelBuilder(osc=mock.MagicMock()) + model_builder.model = mock.MagicMock() + mock_node = mock.MagicMock() + mock_host = mock_node.service["host"] + mock_instances = [mock.MagicMock()] + model_builder.add_instance_node(mock_node, mock_instances) + # verify that when len(instances) <= 1000, limit == len(instance). + model_builder.nova_helper.get_instance_list.assert_called_once_with( + filters={'host': mock_host}, limit=1) + + # verify that when len(instances) > 1000, limit == -1. + mock_instance = mock.Mock() + mock_instances = [mock_instance] * 1001 + model_builder.add_instance_node(mock_node, mock_instances) + model_builder.nova_helper.get_instance_list.assert_called_with( + filters={'host': mock_host}, limit=-1)