openstack
/
nova
Code Issues Proposed changes

Merge "Defaults missing group_policy to 'none'"

This commit is contained in:
Zuul 2019-07-16 17:37:05 +00:00 committed by Gerrit Code Review
parent 0a62d9765b ad4f798362
commit cea01e5f4b
4 changed files with 221 additions and 34 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
doc/source/user/flavors.rst
View File

@ -799,6 +799,16 @@ Numbered groupings of resource classes and traits
* ``none``: Different numbered request groups may be satisfied
by different providers *or* common providers.
.. note::
If more than one group is specified then the ``group_policy`` is
mandatory in the request. However such groups might come from other
sources than flavor extra_spec (e.g. from Neutron ports with QoS
minimum bandwidth policy). If the flavor does not specify any groups
and ``group_policy`` but more than one group is coming from other
sources then nova will default the ``group_policy`` to ``none`` to
avoid scheduler failure.
For example, to create a server with the following VFs:
* One SR-IOV virtual function (VF) on NET1 with bandwidth 10000 bytes/sec

58
nova/scheduler/utils.py
View File

@ -66,6 +66,14 @@ class ResourceRequest(object):
return ', '.join(sorted(
list(str(rg) for rg in list(self._rg_by_id.values()))))
@property
def group_policy(self):
return self._group_policy
@group_policy.setter
def group_policy(self, value):
self._group_policy = value
def get_request_group(self, ident):
if ident not in self._rg_by_id:
rq_grp = objects.RequestGroup(use_same_provider=bool(ident))
@ -211,6 +219,10 @@ class ResourceRequest(object):
for rg in self._rg_by_id.values():
yield rg.resources
def get_num_of_numbered_groups(self):
return len([ident for ident in self._rg_by_id.keys()
if ident is not None])
def merged_resources(self, flavor_resources=None):
"""Returns a merge of {resource_class: amount} for all resource groups.
@ -300,31 +312,14 @@ class ResourceRequest(object):
qparams = []
if self._group_policy is not None:
qparams.append(('group_policy', self._group_policy))
nr_of_numbered_groups = 0
for ident, rg in self._rg_by_id.items():
# [('resourcesN', 'rclass:amount,rclass:amount,...'),
# ('requiredN', 'trait_name,!trait_name,...'),
# ('member_ofN', 'in:uuid,uuid,...'),
# ('member_ofN', 'in:uuid,uuid,...')]
qparams.extend(to_queryparams(rg, ident or ''))
if ident:
nr_of_numbered_groups += 1
if nr_of_numbered_groups >= 2 and not self._group_policy:
# we know this will fail in placement so help the troubleshooting
LOG.warning(
"There is more than one numbered request group in the "
"allocation candidate query but the flavor did not specify "
"any group policy. This query will fail in placement due to "
"the missing group policy. If you specified more than one "
"numbered request group in the flavor extra_spec or booted "
"with more than one neutron port that has resource request "
"(i.e. the port has a QoS minimum bandwidth policy rule "
"attached) then you have to specify the group policy in the "
"flavor extra_spec. If it is OK to let these groups be "
"satisfied by overlapping resource providers then use "
"'group_policy': 'None'. If you want each group to be "
"satisfied from a separate resource provider then use "
"'group_policy': 'isolate'.")
return parse.urlencode(sorted(qparams))
@ -468,9 +463,12 @@ def resources_from_request_spec(ctxt, spec_obj, host_manager):
if rclass not in res_req.merged_resources()}
# Now we don't need (or want) any remaining zero entries - remove them.
res_req.strip_zeros()
numbered_groups_from_flavor = res_req.get_num_of_numbered_groups()
else:
# Start with an empty one
res_req = ResourceRequest()
numbered_groups_from_flavor = 0
# Process any image properties
if 'image' in spec_obj and 'properties' in spec_obj.image:
@ -556,6 +554,28 @@ def resources_from_request_spec(ctxt, spec_obj, host_manager):
for key in spec_obj.scheduler_hints)):
res_req._limit = None
if res_req.get_num_of_numbered_groups() >= 2 and not res_req.group_policy:
LOG.warning(
"There is more than one numbered request group in the "
"allocation candidate query but the flavor did not specify "
"any group policy. This query would fail in placement due to "
"the missing group policy. If you specified more than one "
"numbered request group in the flavor extra_spec then you need to "
"specify the group policy in the flavor extra_spec. If it is OK "
"to let these groups be satisfied by overlapping resource "
"providers then use 'group_policy': 'none'. If you want each "
"group to be satisfied from a separate resource provider then "
"use 'group_policy': 'isolate'.")
if numbered_groups_from_flavor <= 1:
LOG.info(
"At least one numbered request group is defined outside of "
"the flavor (e.g. in a port that has a QoS minimum bandwidth "
"policy rule attached) but the flavor did not specify any "
"group policy. To avoid the placement failure nova defaults "
"the group policy to 'none'.")
res_req.group_policy = 'none'
return res_req

168
nova/tests/unit/scheduler/test_utils.py
View File

@ -362,7 +362,8 @@ class TestUtils(test.NoDBTestCase):
self.context, reqspec, self.mock_host_manager)
self.assertEqual([], req.get_request_group(None).aggregates)
@mock.patch("nova.scheduler.utils.ResourceRequest.from_extra_specs")
@mock.patch("nova.scheduler.utils.ResourceRequest.from_extra_specs",
return_value=utils.ResourceRequest())
def test_process_extra_specs_granular_called(self, mock_proc):
flavor = objects.Flavor(vcpus=1,
memory_mb=1024,
@ -794,20 +795,6 @@ class TestUtils(test.NoDBTestCase):
)
self.assertEqual(expected_querystring, rr.to_querystring())
def test_more_than_one_resource_request_without_group_policy_warns(self):
extra_specs = {
'resources:VCPU': '2',
'resources1:CUSTOM_FOO': '1'
}
rr = utils.ResourceRequest.from_extra_specs(extra_specs)
rr.add_request_group(objects.RequestGroup(resources={'CUSTOM_BAR': 5}))
rr.to_querystring()
self.assertIn(
"There is more than one numbered request group in the allocation "
"candidate query but the flavor did not specify any group policy.",
self.stdlog.logger.output)
def test_resource_request_from_extra_specs_append_request(self):
extra_specs = {
'resources:VCPU': '2',
@ -1138,3 +1125,154 @@ class TestUtils(test.NoDBTestCase):
1.8,
utils.get_weight_multiplier(host1, 'cpu_weight_multiplier', 1.0)
)
class TestResourcesFromRequestGroupDefaultPolicy(test.NoDBTestCase):
"""These test cases assert what happens when the group policy is missing
from the flavor but more than one numbered request group is requested from
various sources. Note that while image can provide required traits for the
resource request those traits are always added to the unnumbered group so
image cannot be a source of additional numbered groups.
"""
def setUp(self):
super(TestResourcesFromRequestGroupDefaultPolicy, self).setUp()
self.context = nova_context.get_admin_context()
self.port_group1 = objects.RequestGroup.from_port_request(
self.context, uuids.port1,
port_resource_request={
"resources": {
"NET_BW_IGR_KILOBIT_PER_SEC": 1000,
"NET_BW_EGR_KILOBIT_PER_SEC": 1000},
"required": ["CUSTOM_PHYSNET_2",
"CUSTOM_VNIC_TYPE_NORMAL"]
})
self.port_group2 = objects.RequestGroup.from_port_request(
self.context, uuids.port2,
port_resource_request={
"resources": {
"NET_BW_IGR_KILOBIT_PER_SEC": 2000,
"NET_BW_EGR_KILOBIT_PER_SEC": 2000},
"required": ["CUSTOM_PHYSNET_3",
"CUSTOM_VNIC_TYPE_DIRECT"]
})
def test_one_group_from_flavor_dont_warn(self):
flavor = objects.Flavor(
vcpus=1, memory_mb=1024, root_gb=10, ephemeral_gb=5, swap=0,
extra_specs={
'resources1:CUSTOM_BAR': '2',
})
request_spec = objects.RequestSpec(
flavor=flavor, image=objects.ImageMeta(), requested_resources=[])
rr = utils.resources_from_request_spec(
self.context, request_spec, host_manager=mock.Mock())
log = self.stdlog.logger.output
self.assertNotIn(
"There is more than one numbered request group in the allocation "
"candidate query but the flavor did not specify any group policy.",
log)
self.assertNotIn(
"To avoid the placement failure nova defaults the group policy to "
"'none'.",
log)
self.assertIsNone(rr.group_policy)
self.assertNotIn('group_policy=none', rr.to_querystring())
def test_one_group_from_port_dont_warn(self):
flavor = objects.Flavor(
vcpus=1, memory_mb=1024, root_gb=10, ephemeral_gb=5, swap=0,
extra_specs={})
request_spec = objects.RequestSpec(
flavor=flavor, image=objects.ImageMeta(),
requested_resources=[self.port_group1])
rr = utils.resources_from_request_spec(
self.context, request_spec, host_manager=mock.Mock())
log = self.stdlog.logger.output
self.assertNotIn(
"There is more than one numbered request group in the allocation "
"candidate query but the flavor did not specify any group policy.",
log)
self.assertNotIn(
"To avoid the placement failure nova defaults the group policy to "
"'none'.",
log)
self.assertIsNone(rr.group_policy)
self.assertNotIn('group_policy=none', rr.to_querystring())
def test_two_groups_from_flavor_only_warns(self):
flavor = objects.Flavor(
vcpus=1, memory_mb=1024, root_gb=10, ephemeral_gb=5, swap=0,
extra_specs={
'resources1:CUSTOM_BAR': '2',
'resources2:CUSTOM_FOO': '1'
})
request_spec = objects.RequestSpec(
flavor=flavor, image=objects.ImageMeta(), requested_resources=[])
rr = utils.resources_from_request_spec(
self.context, request_spec, host_manager=mock.Mock())
log = self.stdlog.logger.output
self.assertIn(
"There is more than one numbered request group in the allocation "
"candidate query but the flavor did not specify any group policy.",
log)
self.assertNotIn(
"To avoid the placement failure nova defaults the group policy to "
"'none'.",
log)
self.assertIsNone(rr.group_policy)
self.assertNotIn('group_policy', rr.to_querystring())
def test_one_group_from_flavor_one_from_port_policy_defaulted(self):
flavor = objects.Flavor(
vcpus=1, memory_mb=1024, root_gb=10, ephemeral_gb=5, swap=0,
extra_specs={
'resources1:CUSTOM_BAR': '2',
})
request_spec = objects.RequestSpec(
flavor=flavor, image=objects.ImageMeta(),
requested_resources=[self.port_group1])
rr = utils.resources_from_request_spec(
self.context, request_spec, host_manager=mock.Mock())
log = self.stdlog.logger.output
self.assertIn(
"There is more than one numbered request group in the allocation "
"candidate query but the flavor did not specify any group policy.",
log)
self.assertIn(
"To avoid the placement failure nova defaults the group policy to "
"'none'.",
log)
self.assertEqual('none', rr.group_policy)
self.assertIn('group_policy=none', rr.to_querystring())
def test_two_groups_from_ports_policy_defaulted(self):
flavor = objects.Flavor(
vcpus=1, memory_mb=1024, root_gb=10, ephemeral_gb=5, swap=0,
extra_specs={})
request_spec = objects.RequestSpec(
flavor=flavor, image=objects.ImageMeta(),
requested_resources=[self.port_group1, self.port_group2])
rr = utils.resources_from_request_spec(
self.context, request_spec, host_manager=mock.Mock())
log = self.stdlog.logger.output
self.assertIn(
"There is more than one numbered request group in the allocation "
"candidate query but the flavor did not specify any group policy.",
log)
self.assertIn(
"To avoid the placement failure nova defaults the group policy to "
"'none'.",
log)
self.assertEqual('none', rr.group_policy)
self.assertIn('group_policy=none', rr.to_querystring())

19
releasenotes/notes/defaulting_group_policy-36f584cd3920818c.yaml Normal file
View File

@ -0,0 +1,19 @@
---
other:
- |
`Numbered request groups`_ can be defined in the flavor extra_spec
but they can come from other sources as well (e.g. neutron ports).
If there is more than one numbered request group in the
allocation candidate query and the flavor does not specify any
group policy then the query will fail in placement as group_policy
is mandatory in this case. Nova previously printed a warning to the
scheduler logs but let the request fail. However the creator of
the flavor cannot know if the flavor later on will be used in a boot
request that has other numbered request groups. So nova will start
defaulting the group_policy to 'none' which means that the resource
providers fulfilling the numbered request groups can overlap.
Nova will only default the group_policy if it is not provided in the flavor
extra_spec, and there is more than one numbered request group present in
the final request, and the flavor only provided one or zero of such groups.
.. _`Numbered request groups`: https://docs.openstack.org/nova/latest/user/flavors.html#extra-specs-numbered-resource-groupings