openstack
/
nova
Code Issues Proposed changes

Move retry from _update to _update_to_placement 

It was noted [1] that we don't need to wrap all of _update in a retry on
ResourceProviderUpdateConflict; only _update_to_placement can raise that
exception, and that exception only indicates a need to redrive with data
ret-GETted from within that method. So this patch moves the retry
decorator further in, to _update_to_placement, to avoid the additional
redundant compute node and pci tracker writes.

[1] https://review.openstack.org/#/c/615705/20/nova/compute/resource_tracker.py@974

Change-Id: I85e567181cdeefde0a9ef91cd460cd200e79bdba
This commit is contained in:
Eric Fried 2019-01-31 09:03:20 -06:00
parent f4ec394e86
commit 6443abaac9
2 changed files with 13 additions and 7 deletions
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6
nova/compute/resource_tracker.py
View File

@ -913,6 +913,9 @@ class ResourceTracker(object):
return True
return False
@retrying.retry(stop_max_attempt_number=4,
retry_on_exception=lambda e: isinstance(
e, exception.ResourceProviderUpdateConflict))
def _update_to_placement(self, context, compute_node, startup):
"""Send resource and inventory changes to placement."""
# NOTE(jianghuaw): Some resources(e.g. VGPU) are not saved in the
@ -969,9 +972,6 @@ class ResourceTracker(object):
self.reportclient.update_from_provider_tree(context, prov_tree,
allocations=allocs)
@retrying.retry(stop_max_attempt_number=4,
retry_on_exception=lambda e: isinstance(
e, exception.ResourceProviderUpdateConflict))
def _update(self, context, compute_node, startup=False):
"""Update partial stats locally and populate them to Scheduler."""
if self._resource_change(compute_node):

14
nova/tests/unit/compute/test_resource_tracker.py
View File

@ -1475,8 +1475,9 @@ class TestUpdateComputeNode(BaseTestCase):
exp_inv[rc_fields.ResourceClass.DISK_GB]['reserved'] = 1
self.assertEqual(exp_inv, ptree.data(new_compute.uuid).inventory)
@mock.patch('nova.objects.ComputeNode.save', new=mock.Mock())
def test_update_retry_success(self):
@mock.patch('nova.compute.resource_tracker.ResourceTracker.'
'_resource_change', return_value=False)
def test_update_retry_success(self, mock_resource_change):
self._setup_rt()
orig_compute = _COMPUTE_NODE_FIXTURES[0].obj_clone()
self.rt.compute_nodes[_NODENAME] = orig_compute
@ -1497,9 +1498,12 @@ class TestUpdateComputeNode(BaseTestCase):
self.rt._update(mock.sentinel.ctx, new_compute)
self.assertEqual(2, ufpt_mock.call_count)
# The retry is restricted to _update_to_placement
self.assertEqual(1, mock_resource_change.call_count)
@mock.patch('nova.objects.ComputeNode.save', new=mock.Mock())
def test_update_retry_raises(self):
@mock.patch('nova.compute.resource_tracker.ResourceTracker.'
'_resource_change', return_value=False)
def test_update_retry_raises(self, mock_resource_change):
self._setup_rt()
orig_compute = _COMPUTE_NODE_FIXTURES[0].obj_clone()
self.rt.compute_nodes[_NODENAME] = orig_compute
@ -1521,6 +1525,8 @@ class TestUpdateComputeNode(BaseTestCase):
self.rt._update, mock.sentinel.ctx, new_compute)
self.assertEqual(4, ufpt_mock.call_count)
# The retry is restricted to _update_to_placement
self.assertEqual(1, mock_resource_change.call_count)
def test_copy_resources_no_update_allocation_ratios(self):
"""Tests that a ComputeNode object's allocation ratio fields are