def _get_request_spec_for_select_destinations(self, attempted_hosts=None):
"""Builds a RequestSpec that can be passed to select_destinations
Used when calling the scheduler to pick a destination host for live
migrating the instance.
:param attempted_hosts: List of host names to ignore in the scheduler.
This is generally at least seeded with the source host.
:returns: nova.objects.RequestSpec object
"""
if not self.request_spec:
# NOTE(sbauza): We were unable to find an original RequestSpec
# object - probably because the instance is old.
# We need to mock that the old way
image = utils.get_image_from_system_metadata(
self.instance.system_metadata)
filter_properties = {'ignore_hosts': attempted_hosts}
request_spec = objects.RequestSpec.from_components(
self.context, self.instance.uuid, image,
self.instance.flavor, self.instance.numa_topology,
self.instance.pci_requests,
filter_properties, None, self.instance.availability_zone
)
else:
request_spec = self.request_spec
# NOTE(sbauza): Force_hosts/nodes needs to be reset
# if we want to make sure that the next destination
# is not forced to be the original host
request_spec.reset_forced_destinations()
scheduler_utils.setup_instance_group(self.context, request_spec)
# We currently only support live migrating to hosts in the same
# cell that the instance lives in, so we need to tell the scheduler
# to limit the applicable hosts based on cell.
cell_mapping = self._get_source_cell_mapping()
LOG.debug('Requesting cell %(cell)s while live migrating',
{'cell': cell_mapping.identity},
instance=self.instance)
if ('requested_destination' in request_spec and
request_spec.requested_destination):
request_spec.requested_destination.cell = cell_mapping
else:
request_spec.requested_destination = objects.Destination(
cell=cell_mapping)
request_spec.ensure_project_and_user_id(self.instance)
request_spec.ensure_network_metadata(self.instance)
compute_utils.heal_reqspec_is_bfv(
self.context, request_spec, self.instance)
return request_spec
def _get_request_spec_for_select_destinations(self, attempted_hosts=None):
"""Builds a RequestSpec that can be passed to select_destinations
Used when calling the scheduler to pick a destination host for live
migrating the instance.
:param attempted_hosts: List of host names to ignore in the scheduler.
This is generally at least seeded with the source host.
:returns: nova.objects.RequestSpec object
"""
request_spec = self.request_spec
# NOTE(sbauza): Force_hosts/nodes needs to be reset
# if we want to make sure that the next destination
# is not forced to be the original host
request_spec.reset_forced_destinations()
port_res_req, req_lvl_params = (
self.network_api.get_requested_resource_for_instance(
self.context, self.instance.uuid))
# NOTE(gibi): When cyborg or other module wants to handle
# similar non-nova resources then here we have to collect
# all the external resource requests in a single list and
# add them to the RequestSpec.
request_spec.requested_resources = port_res_req
request_spec.request_level_params = req_lvl_params
scheduler_utils.setup_instance_group(self.context, request_spec)
# We currently only support live migrating to hosts in the same
# cell that the instance lives in, so we need to tell the scheduler
# to limit the applicable hosts based on cell.
cell_mapping = self._get_source_cell_mapping()
LOG.debug('Requesting cell %(cell)s while live migrating',
{'cell': cell_mapping.identity},
instance=self.instance)
if ('requested_destination' in request_spec
and request_spec.requested_destination):
request_spec.requested_destination.cell = cell_mapping
else:
request_spec.requested_destination = objects.Destination(
cell=cell_mapping)
request_spec.ensure_project_and_user_id(self.instance)
request_spec.ensure_network_information(self.instance)
compute_utils.heal_reqspec_is_bfv(self.context, request_spec,
self.instance)
return request_spec
def _get_request_spec_for_select_destinations(self, attempted_hosts=None):
"""Builds a RequestSpec that can be passed to select_destinations
Used when calling the scheduler to pick a destination host for live
migrating the instance.
:param attempted_hosts: List of host names to ignore in the scheduler.
This is generally at least seeded with the source host.
:returns: nova.objects.RequestSpec object
"""
request_spec = self.request_spec
# NOTE(sbauza): Force_hosts/nodes needs to be reset
# if we want to make sure that the next destination
# is not forced to be the original host
request_spec.reset_forced_destinations()
# TODO(gibi): We need to make sure that the requested_resources field
# is re calculated based on neutron ports.
scheduler_utils.setup_instance_group(self.context, request_spec)
# We currently only support live migrating to hosts in the same
# cell that the instance lives in, so we need to tell the scheduler
# to limit the applicable hosts based on cell.
cell_mapping = self._get_source_cell_mapping()
LOG.debug('Requesting cell %(cell)s while live migrating',
{'cell': cell_mapping.identity},
instance=self.instance)
if ('requested_destination' in request_spec
and request_spec.requested_destination):
request_spec.requested_destination.cell = cell_mapping
else:
request_spec.requested_destination = objects.Destination(
cell=cell_mapping)
request_spec.ensure_project_and_user_id(self.instance)
request_spec.ensure_network_metadata(self.instance)
compute_utils.heal_reqspec_is_bfv(self.context, request_spec,
self.instance)
return request_spec
def _get_request_spec_for_select_destinations(self, attempted_hosts=None):
"""Builds a RequestSpec that can be passed to select_destinations
Used when calling the scheduler to pick a destination host for live
migrating the instance.
:param attempted_hosts: List of host names to ignore in the scheduler.
This is generally at least seeded with the source host.
:returns: nova.objects.RequestSpec object
"""
request_spec = self.request_spec
# NOTE(sbauza): Force_hosts/nodes needs to be reset
# if we want to make sure that the next destination
# is not forced to be the original host
request_spec.reset_forced_destinations()
# TODO(gibi): We need to make sure that the requested_resources field
# is re calculated based on neutron ports.
scheduler_utils.setup_instance_group(self.context, request_spec)
# We currently only support live migrating to hosts in the same
# cell that the instance lives in, so we need to tell the scheduler
# to limit the applicable hosts based on cell.
cell_mapping = self._get_source_cell_mapping()
LOG.debug('Requesting cell %(cell)s while live migrating',
{'cell': cell_mapping.identity},
instance=self.instance)
if ('requested_destination' in request_spec and
request_spec.requested_destination):
request_spec.requested_destination.cell = cell_mapping
else:
request_spec.requested_destination = objects.Destination(
cell=cell_mapping)
request_spec.ensure_project_and_user_id(self.instance)
request_spec.ensure_network_metadata(self.instance)
compute_utils.heal_reqspec_is_bfv(
self.context, request_spec, self.instance)
return request_spec
def _execute(self):
# NOTE(sbauza): Force_hosts/nodes needs to be reset if we want to make
# sure that the next destination is not forced to be the original host.
# This needs to be done before the populate_retry call otherwise
# retries will be disabled if the server was created with a forced
# host/node.
self.request_spec.reset_forced_destinations()
# TODO(sbauza): Remove once all the scheduler.utils methods accept a
# RequestSpec object in the signature.
legacy_props = self.request_spec.to_legacy_filter_properties_dict()
scheduler_utils.setup_instance_group(self.context, self.request_spec)
# If a target host is set in a requested destination,
# 'populate_retry' need not be executed.
if not ('requested_destination' in self.request_spec and
self.request_spec.requested_destination and
'host' in self.request_spec.requested_destination):
scheduler_utils.populate_retry(legacy_props,
self.instance.uuid)
port_res_req = self.network_api.get_requested_resource_for_instance(
self.context, self.instance.uuid)
# NOTE(gibi): When cyborg or other module wants to handle similar
# non-nova resources then here we have to collect all the external
# resource requests in a single list and add them to the RequestSpec.
self.request_spec.requested_resources = port_res_req
self._restrict_request_spec_to_cell(legacy_props)
# Once _preallocate_migration() is done, the source node allocation is
# moved from the instance consumer to the migration record consumer,
# and the instance consumer doesn't have any allocations. If this is
# the first time through here (not a reschedule), select_destinations
# below will allocate resources on the selected destination node for
# the instance consumer. If we're rescheduling, host_list is not None
# and we'll call claim_resources for the instance and the selected
# alternate. If we exhaust our alternates and raise MaxRetriesExceeded,
# the rollback() method should revert the allocation swaparoo and move
# the source node allocation from the migration record back to the
# instance record.
migration = self._preallocate_migration()
self.request_spec.ensure_project_and_user_id(self.instance)
self.request_spec.ensure_network_metadata(self.instance)
compute_utils.heal_reqspec_is_bfv(
self.context, self.request_spec, self.instance)
# On an initial call to migrate, 'self.host_list' will be None, so we
# have to call the scheduler to get a list of acceptable hosts to
# migrate to. That list will consist of a selected host, along with
# zero or more alternates. On a reschedule, though, the alternates will
# be passed to this object and stored in 'self.host_list', so we can
# pop the first alternate from the list to use for the destination, and
# pass the remaining alternates to the compute.
if self.host_list is None:
selection = self._schedule()
else:
# This is a reschedule that will use the supplied alternate hosts
# in the host_list as destinations.
selection = self._reschedule()
scheduler_utils.populate_filter_properties(legacy_props, selection)
# context is not serializable
legacy_props.pop('context', None)
(host, node) = (selection.service_host, selection.nodename)
# The availability_zone field was added in v1.1 of the Selection
# object so make sure to handle the case where it is missing.
if 'availability_zone' in selection:
self.instance.availability_zone = selection.availability_zone
else:
self.instance.availability_zone = (
availability_zones.get_host_availability_zone(
self.context, host))
LOG.debug("Calling prep_resize with selected host: %s; "
"Selected node: %s; Alternates: %s", host, node,
self.host_list, instance=self.instance)
# RPC cast to the destination host to start the migration process.
self.compute_rpcapi.prep_resize(
# NOTE(mriedem): Using request_spec.image here is potentially
# dangerous if it is not kept up to date (i.e. rebuild/unshelve);
# seems like the sane thing to do would be to pass the current
# instance.image_meta since that is what MoveClaim will use for
# any NUMA topology claims on the destination host...
self.context, self.instance, self.request_spec.image,
self.flavor, host, migration,
request_spec=self.request_spec, filter_properties=legacy_props,
node=node, clean_shutdown=self.clean_shutdown,
host_list=self.host_list)
def _execute(self):
# TODO(sbauza): Remove once all the scheduler.utils methods accept a
# RequestSpec object in the signature.
legacy_props = self.request_spec.to_legacy_filter_properties_dict()
scheduler_utils.setup_instance_group(self.context, self.request_spec)
# If a target host is set in a requested destination,
# 'populate_retry' need not be executed.
if not ('requested_destination' in self.request_spec and
self.request_spec.requested_destination and
'host' in self.request_spec.requested_destination):
scheduler_utils.populate_retry(legacy_props,
self.instance.uuid)
# NOTE(sbauza): Force_hosts/nodes needs to be reset
# if we want to make sure that the next destination
# is not forced to be the original host
self.request_spec.reset_forced_destinations()
# TODO(gibi): We need to make sure that the requested_resources field
# is re calculated based on neutron ports.
self._restrict_request_spec_to_cell(legacy_props)
# Once _preallocate_migration() is done, the source node allocation is
# moved from the instance consumer to the migration record consumer,
# and the instance consumer doesn't have any allocations. If this is
# the first time through here (not a reschedule), select_destinations
# below will allocate resources on the selected destination node for
# the instance consumer. If we're rescheduling, host_list is not None
# and we'll call claim_resources for the instance and the selected
# alternate. If we exhaust our alternates and raise MaxRetriesExceeded,
# the rollback() method should revert the allocation swaparoo and move
# the source node allocation from the migration record back to the
# instance record.
migration = self._preallocate_migration()
self.request_spec.ensure_project_and_user_id(self.instance)
self.request_spec.ensure_network_metadata(self.instance)
compute_utils.heal_reqspec_is_bfv(
self.context, self.request_spec, self.instance)
# On an initial call to migrate, 'self.host_list' will be None, so we
# have to call the scheduler to get a list of acceptable hosts to
# migrate to. That list will consist of a selected host, along with
# zero or more alternates. On a reschedule, though, the alternates will
# be passed to this object and stored in 'self.host_list', so we can
# pop the first alternate from the list to use for the destination, and
# pass the remaining alternates to the compute.
if self.host_list is None:
selection_lists = self.query_client.select_destinations(
self.context, self.request_spec, [self.instance.uuid],
return_objects=True, return_alternates=True)
# Since there is only ever one instance to migrate per call, we
# just need the first returned element.
selection_list = selection_lists[0]
# The selected host is the first item in the list, with the
# alternates being the remainder of the list.
selection, self.host_list = selection_list[0], selection_list[1:]
else:
# This is a reschedule that will use the supplied alternate hosts
# in the host_list as destinations. Since the resources on these
# alternates may have been consumed and might not be able to
# support the migrated instance, we need to first claim the
# resources to verify the host still has sufficient availabile
# resources.
elevated = self.context.elevated()
host_available = False
while self.host_list and not host_available:
selection = self.host_list.pop(0)
if selection.allocation_request:
alloc_req = jsonutils.loads(selection.allocation_request)
else:
alloc_req = None
if alloc_req:
# If this call succeeds, the resources on the destination
# host will be claimed by the instance.
host_available = scheduler_utils.claim_resources(
elevated, self.reportclient, self.request_spec,
self.instance.uuid, alloc_req,
selection.allocation_request_version)
else:
# Some deployments use different schedulers that do not
# use Placement, so they will not have an
# allocation_request to claim with. For those cases,
# there is no concept of claiming, so just assume that
# the host is valid.
host_available = True
# There are no more available hosts. Raise a MaxRetriesExceeded
# exception in that case.
if not host_available:
reason = ("Exhausted all hosts available for retrying build "
"failures for instance %(instance_uuid)s." %
{"instance_uuid": self.instance.uuid})
raise exception.MaxRetriesExceeded(reason=reason)
scheduler_utils.populate_filter_properties(legacy_props, selection)
# context is not serializable
legacy_props.pop('context', None)
(host, node) = (selection.service_host, selection.nodename)
self.instance.availability_zone = (
availability_zones.get_host_availability_zone(
self.context, host))
LOG.debug("Calling prep_resize with selected host: %s; "
"Selected node: %s; Alternates: %s", host, node,
self.host_list, instance=self.instance)
# RPC cast to the destination host to start the migration process.
self.compute_rpcapi.prep_resize(
# NOTE(mriedem): Using request_spec.image here is potentially
# dangerous if it is not kept up to date (i.e. rebuild/unshelve);
# seems like the sane thing to do would be to pass the current
# instance.image_meta since that is what MoveClaim will use for
# any NUMA topology claims on the destination host...
self.context, self.instance, self.request_spec.image,
self.flavor, host, migration,
request_spec=self.request_spec, filter_properties=legacy_props,
node=node, clean_shutdown=self.clean_shutdown,
host_list=self.host_list)
def _execute(self):
# TODO(sbauza): Remove that once prep_resize() accepts a RequestSpec
# object in the signature and all the scheduler.utils methods too
legacy_spec = self.request_spec.to_legacy_request_spec_dict()
legacy_props = self.request_spec.to_legacy_filter_properties_dict()
scheduler_utils.setup_instance_group(self.context, self.request_spec)
# If a target host is set in a requested destination,
# 'populate_retry' need not be executed.
if not ('requested_destination' in self.request_spec
and self.request_spec.requested_destination
and 'host' in self.request_spec.requested_destination):
scheduler_utils.populate_retry(legacy_props, self.instance.uuid)
# NOTE(sbauza): Force_hosts/nodes needs to be reset
# if we want to make sure that the next destination
# is not forced to be the original host
self.request_spec.reset_forced_destinations()
# NOTE(danms): Right now we only support migrate to the same
# cell as the current instance, so request that the scheduler
# limit thusly.
instance_mapping = objects.InstanceMapping.get_by_instance_uuid(
self.context, self.instance.uuid)
LOG.debug('Requesting cell %(cell)s while migrating',
{'cell': instance_mapping.cell_mapping.identity},
instance=self.instance)
if ('requested_destination' in self.request_spec
and self.request_spec.requested_destination):
self.request_spec.requested_destination.cell = (
instance_mapping.cell_mapping)
# NOTE(takashin): In the case that the target host is specified,
# if the migration is failed, it is not necessary to retry
# the cold migration to the same host. So make sure that
# reschedule will not occur.
if 'host' in self.request_spec.requested_destination:
legacy_props.pop('retry', None)
self.request_spec.retry = None
else:
self.request_spec.requested_destination = objects.Destination(
cell=instance_mapping.cell_mapping)
# Once _preallocate_migration() is done, the source node allocation is
# moved from the instance consumer to the migration record consumer,
# and the instance consumer doesn't have any allocations. If this is
# the first time through here (not a reschedule), select_destinations
# below will allocate resources on the selected destination node for
# the instance consumer. If we're rescheduling, host_list is not None
# and we'll call claim_resources for the instance and the selected
# alternate. If we exhaust our alternates and raise MaxRetriesExceeded,
# the rollback() method should revert the allocation swaparoo and move
# the source node allocation from the migration record back to the
# instance record.
migration = self._preallocate_migration()
self.request_spec.ensure_project_and_user_id(self.instance)
compute_utils.heal_reqspec_is_bfv(self.context, self.request_spec,
self.instance)
# On an initial call to migrate, 'self.host_list' will be None, so we
# have to call the scheduler to get a list of acceptable hosts to
# migrate to. That list will consist of a selected host, along with
# zero or more alternates. On a reschedule, though, the alternates will
# be passed to this object and stored in 'self.host_list', so we can
# pop the first alternate from the list to use for the destination, and
# pass the remaining alternates to the compute.
if self.host_list is None:
selection_lists = self.scheduler_client.select_destinations(
self.context,
self.request_spec, [self.instance.uuid],
return_objects=True,
return_alternates=True)
# Since there is only ever one instance to migrate per call, we
# just need the first returned element.
selection_list = selection_lists[0]
# The selected host is the first item in the list, with the
# alternates being the remainder of the list.
selection, self.host_list = selection_list[0], selection_list[1:]
else:
# This is a reschedule that will use the supplied alternate hosts
# in the host_list as destinations. Since the resources on these
# alternates may have been consumed and might not be able to
# support the migrated instance, we need to first claim the
# resources to verify the host still has sufficient availabile
# resources.
elevated = self.context.elevated()
host_available = False
while self.host_list and not host_available:
selection = self.host_list.pop(0)
if selection.allocation_request:
alloc_req = jsonutils.loads(selection.allocation_request)
else:
alloc_req = None
if alloc_req:
# If this call succeeds, the resources on the destination
# host will be claimed by the instance.
host_available = scheduler_utils.claim_resources(
elevated, self.reportclient, self.request_spec,
self.instance.uuid, alloc_req,
selection.allocation_request_version)
else:
# Some deployments use different schedulers that do not
# use Placement, so they will not have an
# allocation_request to claim with. For those cases,
# there is no concept of claiming, so just assume that
# the host is valid.
host_available = True
# There are no more available hosts. Raise a MaxRetriesExceeded
# exception in that case.
if not host_available:
reason = ("Exhausted all hosts available for retrying build "
"failures for instance %(instance_uuid)s." % {
"instance_uuid": self.instance.uuid
})
raise exception.MaxRetriesExceeded(reason=reason)
scheduler_utils.populate_filter_properties(legacy_props, selection)
# context is not serializable
legacy_props.pop('context', None)
(host, node) = (selection.service_host, selection.nodename)
self.instance.availability_zone = (
availability_zones.get_host_availability_zone(self.context, host))
# FIXME(sbauza): Serialize/Unserialize the legacy dict because of
# oslo.messaging #1529084 to transform datetime values into strings.
# tl;dr: datetimes in dicts are not accepted as correct values by the
# rpc fake driver.
legacy_spec = jsonutils.loads(jsonutils.dumps(legacy_spec))
LOG.debug(
"Calling prep_resize with selected host: %s; "
"Selected node: %s; Alternates: %s",
host,
node,
self.host_list,
instance=self.instance)
# RPC cast to the destination host to start the migration process.
self.compute_rpcapi.prep_resize(self.context,
self.instance,
legacy_spec['image'],
self.flavor,
host,
migration,
request_spec=legacy_spec,
filter_properties=legacy_props,
node=node,
clean_shutdown=self.clean_shutdown,
host_list=self.host_list)
def _execute(self):
# TODO(sbauza): Remove once all the scheduler.utils methods accept a
# RequestSpec object in the signature.
legacy_props = self.request_spec.to_legacy_filter_properties_dict()
scheduler_utils.setup_instance_group(self.context, self.request_spec)
# If a target host is set in a requested destination,
# 'populate_retry' need not be executed.
if not ('requested_destination' in self.request_spec
and self.request_spec.requested_destination
and 'host' in self.request_spec.requested_destination):
scheduler_utils.populate_retry(legacy_props, self.instance.uuid)
# NOTE(sbauza): Force_hosts/nodes needs to be reset
# if we want to make sure that the next destination
# is not forced to be the original host
self.request_spec.reset_forced_destinations()
# TODO(gibi): We need to make sure that the requested_resources field
# is re calculated based on neutron ports.
self._restrict_request_spec_to_cell(legacy_props)
# Once _preallocate_migration() is done, the source node allocation is
# moved from the instance consumer to the migration record consumer,
# and the instance consumer doesn't have any allocations. If this is
# the first time through here (not a reschedule), select_destinations
# below will allocate resources on the selected destination node for
# the instance consumer. If we're rescheduling, host_list is not None
# and we'll call claim_resources for the instance and the selected
# alternate. If we exhaust our alternates and raise MaxRetriesExceeded,
# the rollback() method should revert the allocation swaparoo and move
# the source node allocation from the migration record back to the
# instance record.
migration = self._preallocate_migration()
self.request_spec.ensure_project_and_user_id(self.instance)
self.request_spec.ensure_network_metadata(self.instance)
compute_utils.heal_reqspec_is_bfv(self.context, self.request_spec,
self.instance)
# On an initial call to migrate, 'self.host_list' will be None, so we
# have to call the scheduler to get a list of acceptable hosts to
# migrate to. That list will consist of a selected host, along with
# zero or more alternates. On a reschedule, though, the alternates will
# be passed to this object and stored in 'self.host_list', so we can
# pop the first alternate from the list to use for the destination, and
# pass the remaining alternates to the compute.
if self.host_list is None:
selection_lists = self.query_client.select_destinations(
self.context,
self.request_spec, [self.instance.uuid],
return_objects=True,
return_alternates=True)
# Since there is only ever one instance to migrate per call, we
# just need the first returned element.
selection_list = selection_lists[0]
# The selected host is the first item in the list, with the
# alternates being the remainder of the list.
selection, self.host_list = selection_list[0], selection_list[1:]
else:
# This is a reschedule that will use the supplied alternate hosts
# in the host_list as destinations. Since the resources on these
# alternates may have been consumed and might not be able to
# support the migrated instance, we need to first claim the
# resources to verify the host still has sufficient availabile
# resources.
elevated = self.context.elevated()
host_available = False
while self.host_list and not host_available:
selection = self.host_list.pop(0)
if selection.allocation_request:
alloc_req = jsonutils.loads(selection.allocation_request)
else:
alloc_req = None
if alloc_req:
# If this call succeeds, the resources on the destination
# host will be claimed by the instance.
host_available = scheduler_utils.claim_resources(
elevated, self.reportclient, self.request_spec,
self.instance.uuid, alloc_req,
selection.allocation_request_version)
else:
# Some deployments use different schedulers that do not
# use Placement, so they will not have an
# allocation_request to claim with. For those cases,
# there is no concept of claiming, so just assume that
# the host is valid.
host_available = True
# There are no more available hosts. Raise a MaxRetriesExceeded
# exception in that case.
if not host_available:
reason = ("Exhausted all hosts available for retrying build "
"failures for instance %(instance_uuid)s." % {
"instance_uuid": self.instance.uuid
})
raise exception.MaxRetriesExceeded(reason=reason)
scheduler_utils.populate_filter_properties(legacy_props, selection)
# context is not serializable
legacy_props.pop('context', None)
(host, node) = (selection.service_host, selection.nodename)
self.instance.availability_zone = (
availability_zones.get_host_availability_zone(self.context, host))
LOG.debug(
"Calling prep_resize with selected host: %s; "
"Selected node: %s; Alternates: %s",
host,
node,
self.host_list,
instance=self.instance)
# RPC cast to the destination host to start the migration process.
self.compute_rpcapi.prep_resize(
# NOTE(mriedem): Using request_spec.image here is potentially
# dangerous if it is not kept up to date (i.e. rebuild/unshelve);
# seems like the sane thing to do would be to pass the current
# instance.image_meta since that is what MoveClaim will use for
# any NUMA topology claims on the destination host...
self.context,
self.instance,
self.request_spec.image,
self.flavor,
host,
migration,
request_spec=self.request_spec,
filter_properties=legacy_props,
node=node,
clean_shutdown=self.clean_shutdown,
host_list=self.host_list)
def _execute(self):
# TODO(sbauza): Remove that once prep_resize() accepts a RequestSpec
# object in the signature and all the scheduler.utils methods too
legacy_spec = self.request_spec.to_legacy_request_spec_dict()
legacy_props = self.request_spec.to_legacy_filter_properties_dict()
scheduler_utils.setup_instance_group(self.context, self.request_spec)
# If a target host is set in a requested destination,
# 'populate_retry' need not be executed.
if not ('requested_destination' in self.request_spec and
self.request_spec.requested_destination and
'host' in self.request_spec.requested_destination):
scheduler_utils.populate_retry(legacy_props,
self.instance.uuid)
# NOTE(sbauza): Force_hosts/nodes needs to be reset
# if we want to make sure that the next destination
# is not forced to be the original host
self.request_spec.reset_forced_destinations()
# NOTE(danms): Right now we only support migrate to the same
# cell as the current instance, so request that the scheduler
# limit thusly.
instance_mapping = objects.InstanceMapping.get_by_instance_uuid(
self.context, self.instance.uuid)
LOG.debug('Requesting cell %(cell)s while migrating',
{'cell': instance_mapping.cell_mapping.identity},
instance=self.instance)
if ('requested_destination' in self.request_spec and
self.request_spec.requested_destination):
self.request_spec.requested_destination.cell = (
instance_mapping.cell_mapping)
# NOTE(takashin): In the case that the target host is specified,
# if the migration is failed, it is not necessary to retry
# the cold migration to the same host. So make sure that
# reschedule will not occur.
if 'host' in self.request_spec.requested_destination:
legacy_props.pop('retry', None)
self.request_spec.retry = None
else:
self.request_spec.requested_destination = objects.Destination(
cell=instance_mapping.cell_mapping)
# Once _preallocate_migration() is done, the source node allocation is
# moved from the instance consumer to the migration record consumer,
# and the instance consumer doesn't have any allocations. If this is
# the first time through here (not a reschedule), select_destinations
# below will allocate resources on the selected destination node for
# the instance consumer. If we're rescheduling, host_list is not None
# and we'll call claim_resources for the instance and the selected
# alternate. If we exhaust our alternates and raise MaxRetriesExceeded,
# the rollback() method should revert the allocation swaparoo and move
# the source node allocation from the migration record back to the
# instance record.
migration = self._preallocate_migration()
self.request_spec.ensure_project_and_user_id(self.instance)
self.request_spec.ensure_network_metadata(self.instance)
compute_utils.heal_reqspec_is_bfv(
self.context, self.request_spec, self.instance)
# On an initial call to migrate, 'self.host_list' will be None, so we
# have to call the scheduler to get a list of acceptable hosts to
# migrate to. That list will consist of a selected host, along with
# zero or more alternates. On a reschedule, though, the alternates will
# be passed to this object and stored in 'self.host_list', so we can
# pop the first alternate from the list to use for the destination, and
# pass the remaining alternates to the compute.
if self.host_list is None:
selection_lists = self.scheduler_client.select_destinations(
self.context, self.request_spec, [self.instance.uuid],
return_objects=True, return_alternates=True)
# Since there is only ever one instance to migrate per call, we
# just need the first returned element.
selection_list = selection_lists[0]
# The selected host is the first item in the list, with the
# alternates being the remainder of the list.
selection, self.host_list = selection_list[0], selection_list[1:]
else:
# This is a reschedule that will use the supplied alternate hosts
# in the host_list as destinations. Since the resources on these
# alternates may have been consumed and might not be able to
# support the migrated instance, we need to first claim the
# resources to verify the host still has sufficient availabile
# resources.
elevated = self.context.elevated()
host_available = False
while self.host_list and not host_available:
selection = self.host_list.pop(0)
if selection.allocation_request:
alloc_req = jsonutils.loads(selection.allocation_request)
else:
alloc_req = None
if alloc_req:
# If this call succeeds, the resources on the destination
# host will be claimed by the instance.
host_available = scheduler_utils.claim_resources(
elevated, self.reportclient, self.request_spec,
self.instance.uuid, alloc_req,
selection.allocation_request_version)
else:
# Some deployments use different schedulers that do not
# use Placement, so they will not have an
# allocation_request to claim with. For those cases,
# there is no concept of claiming, so just assume that
# the host is valid.
host_available = True
# There are no more available hosts. Raise a MaxRetriesExceeded
# exception in that case.
if not host_available:
reason = ("Exhausted all hosts available for retrying build "
"failures for instance %(instance_uuid)s." %
{"instance_uuid": self.instance.uuid})
raise exception.MaxRetriesExceeded(reason=reason)
scheduler_utils.populate_filter_properties(legacy_props, selection)
# context is not serializable
legacy_props.pop('context', None)
(host, node) = (selection.service_host, selection.nodename)
self.instance.availability_zone = (
availability_zones.get_host_availability_zone(
self.context, host))
# FIXME(sbauza): Serialize/Unserialize the legacy dict because of
# oslo.messaging #1529084 to transform datetime values into strings.
# tl;dr: datetimes in dicts are not accepted as correct values by the
# rpc fake driver.
legacy_spec = jsonutils.loads(jsonutils.dumps(legacy_spec))
LOG.debug("Calling prep_resize with selected host: %s; "
"Selected node: %s; Alternates: %s", host, node,
self.host_list, instance=self.instance)
# RPC cast to the destination host to start the migration process.
self.compute_rpcapi.prep_resize(
self.context, self.instance, legacy_spec['image'],
self.flavor, host, migration,
request_spec=legacy_spec, filter_properties=legacy_props,
node=node, clean_shutdown=self.clean_shutdown,
host_list=self.host_list)
