deb-manila/manila/scheduler/host_manager.py
Clinton Knight af2e103514 Reorganize scheduler and merge code from Oslo incubator
With oslo-incubator going away, we need to pull those classes into
the Manila code base, along with their unit tests.  This presents a
good opportunity to do some long-needed housecleaning.  This commit
does the following:

1. Moves the scheduler classes from openstack.common to manila.
2. Adds the unit tests from olso-incubator into Manila.
3. Removes duplication among the combined scheduler modules.
4. Moves scheduler drivers into a sub-module.
5. Normalizes class and module naming throughout the scheduler.
6. Splits some unit test files so they match the names of the
   modules that they test.
7. Converts usage of mox & oslotest to mock & unittest.
8. Adds a few unit tests to boost coverage levels.

Implements: blueprint reorganize-manila-scheduler
Change-Id: I7aa237e17787e89a95bb198093ea9bc9498279cd
2015-12-01 20:54:17 +00:00

589 lines
23 KiB
Python

# Copyright (c) 2011 OpenStack, LLC.
# Copyright (c) 2015 Rushil Chugh
# Copyright (c) 2015 Clinton Knight
# Copyright (c) 2015 EMC Corporation
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
"""
Manage hosts in the current zone.
"""
import re
try:
from UserDict import IterableUserDict # noqa
except ImportError:
from collections import UserDict as IterableUserDict # noqa
from oslo_config import cfg
from oslo_log import log
from oslo_utils import timeutils
import six
from manila import db
from manila import exception
from manila.i18n import _LI, _LW
from manila.scheduler.filters import base_host as base_host_filter
from manila.scheduler.weighers import base_host as base_host_weigher
from manila.share import utils as share_utils
from manila import utils
host_manager_opts = [
cfg.ListOpt('scheduler_default_filters',
default=[
'AvailabilityZoneFilter',
'CapacityFilter',
'CapabilitiesFilter',
'ConsistencyGroupFilter',
],
help='Which filter class names to use for filtering hosts '
'when not specified in the request.'),
cfg.ListOpt('scheduler_default_weighers',
default=[
'CapacityWeigher'
],
help='Which weigher class names to use for weighing hosts.')
]
CONF = cfg.CONF
CONF.register_opts(host_manager_opts)
CONF.import_opt('max_over_subscription_ratio', 'manila.share.driver')
LOG = log.getLogger(__name__)
class ReadOnlyDict(IterableUserDict):
"""A read-only dict."""
def __init__(self, source=None):
self.data = {}
self.update(source)
def __setitem__(self, key, item):
raise TypeError
def __delitem__(self, key):
raise TypeError
def clear(self):
raise TypeError
def pop(self, key, *args):
raise TypeError
def popitem(self):
raise TypeError
def update(self, source=None):
if source is None:
return
elif isinstance(source, IterableUserDict):
self.data = source.data
elif isinstance(source, type({})):
self.data = source
else:
raise TypeError
class HostState(object):
"""Mutable and immutable information tracked for a host."""
def __init__(self, host, capabilities=None, service=None):
self.capabilities = None
self.service = None
self.host = host
self.update_capabilities(capabilities, service)
self.share_backend_name = None
self.vendor_name = None
self.driver_version = 0
self.storage_protocol = None
self.QoS_support = False
# Mutable available resources.
# These will change as resources are virtually "consumed".
self.total_capacity_gb = 0
self.free_capacity_gb = None
self.reserved_percentage = 0
self.allocated_capacity_gb = 0
# NOTE(xyang): The apparent allocated space indicating how much
# capacity has been provisioned. This could be the sum of sizes
# of all shares on a backend, which could be greater than or
# equal to the allocated_capacity_gb.
self.provisioned_capacity_gb = 0
self.max_over_subscription_ratio = 1.0
self.thin_provisioning = False
self.driver_handles_share_servers = False
self.snapshot_support = True
self.consistency_group_support = False
self.dedupe = False
self.compression = False
# PoolState for all pools
self.pools = {}
self.updated = None
def update_capabilities(self, capabilities=None, service=None):
# Read-only capability dicts
if capabilities is None:
capabilities = {}
self.capabilities = ReadOnlyDict(capabilities)
if service is None:
service = {}
self.service = ReadOnlyDict(service)
def update_from_share_capability(self, capability, service=None):
"""Update information about a host from its share_node info.
'capability' is the status info reported by share backend, a typical
capability looks like this:
capability = {
'share_backend_name': 'Local NFS', #\
'vendor_name': 'OpenStack', # backend level
'driver_version': '1.0', # mandatory/fixed
'storage_protocol': 'NFS', #/ stats&capabilities
'active_shares': 10, #\
'IOPS_provisioned': 30000, # optional custom
'fancy_capability_1': 'eat', # stats & capabilities
'fancy_capability_2': 'drink', #/
'pools': [
{'pool_name': '1st pool', #\
'total_capacity_gb': 500, # mandatory stats for
'free_capacity_gb': 230, # pools
'allocated_capacity_gb': 270, # |
'QoS_support': 'False', # |
'reserved_percentage': 0, #/
'dying_disks': 100, #\
'super_hero_1': 'spider-man', # optional custom
'super_hero_2': 'flash', # stats & capabilities
'super_hero_3': 'neoncat' #/
},
{'pool_name': '2nd pool',
'total_capacity_gb': 1024,
'free_capacity_gb': 1024,
'allocated_capacity_gb': 0,
'QoS_support': 'False',
'reserved_percentage': 0,
'dying_disks': 200,
'super_hero_1': 'superman',
'super_hero_2': ' ',
'super_hero_2': 'Hulk',
}
]
}
"""
self.update_capabilities(capability, service)
if capability:
if self.updated and self.updated > capability['timestamp']:
return
# Update backend level info
self.update_backend(capability)
# Update pool level info
self.update_pools(capability, service)
def update_pools(self, capability, service):
"""Update storage pools information from backend reported info."""
if not capability:
return
pools = capability.get('pools', None)
active_pools = set()
if pools and isinstance(pools, list):
# Update all pools stats according to information from list
# of pools in share capacity
for pool_cap in pools:
pool_name = pool_cap['pool_name']
self._append_backend_info(pool_cap)
cur_pool = self.pools.get(pool_name, None)
if not cur_pool:
# Add new pool
cur_pool = PoolState(self.host, pool_cap, pool_name)
self.pools[pool_name] = cur_pool
cur_pool.update_from_share_capability(pool_cap, service)
active_pools.add(pool_name)
elif pools is None:
# To handle legacy driver that doesn't report pool
# information in the capability, we have to prepare
# a pool from backend level info, or to update the one
# we created in self.pools.
pool_name = self.share_backend_name
if pool_name is None:
# To get DEFAULT_POOL_NAME
pool_name = share_utils.extract_host(self.host, 'pool', True)
if len(self.pools) == 0:
# No pool was there
single_pool = PoolState(self.host, capability, pool_name)
self._append_backend_info(capability)
self.pools[pool_name] = single_pool
else:
# This is a update from legacy driver
try:
single_pool = self.pools[pool_name]
except KeyError:
single_pool = PoolState(self.host, capability, pool_name)
self._append_backend_info(capability)
self.pools[pool_name] = single_pool
single_pool.update_from_share_capability(capability, service)
active_pools.add(pool_name)
# Remove non-active pools from self.pools
nonactive_pools = set(self.pools.keys()) - active_pools
for pool in nonactive_pools:
LOG.debug("Removing non-active pool %(pool)s @ %(host)s "
"from scheduler cache.",
{'pool': pool, 'host': self.host})
del self.pools[pool]
def _append_backend_info(self, pool_cap):
# Fill backend level info to pool if needed.
if not pool_cap.get('share_backend_name'):
pool_cap['share_backend_name'] = self.share_backend_name
if not pool_cap.get('storage_protocol'):
pool_cap['storage_protocol'] = self.storage_protocol
if not pool_cap.get('vendor_name'):
pool_cap['vendor_name'] = self.vendor_name
if not pool_cap.get('driver_version'):
pool_cap['driver_version'] = self.driver_version
if not pool_cap.get('timestamp'):
pool_cap['timestamp'] = self.updated
if not pool_cap.get('storage_protocol'):
pool_cap['storage_protocol'] = self.storage_protocol
if 'driver_handles_share_servers' not in pool_cap:
pool_cap['driver_handles_share_servers'] = (
self.driver_handles_share_servers)
if 'snapshot_support' not in pool_cap:
pool_cap['snapshot_support'] = self.snapshot_support
if not pool_cap.get('consistency_group_support'):
pool_cap['consistency_group_support'] = \
self.consistency_group_support
if 'dedupe' not in pool_cap:
pool_cap['dedupe'] = self.dedupe
if 'compression' not in pool_cap:
pool_cap['compression'] = self.compression
def update_backend(self, capability):
self.share_backend_name = capability.get('share_backend_name')
self.vendor_name = capability.get('vendor_name')
self.driver_version = capability.get('driver_version')
self.storage_protocol = capability.get('storage_protocol')
self.driver_handles_share_servers = capability.get(
'driver_handles_share_servers')
self.snapshot_support = capability.get('snapshot_support')
self.consistency_group_support = capability.get(
'consistency_group_support', False)
self.updated = capability['timestamp']
def consume_from_share(self, share):
"""Incrementally update host state from an share."""
if (isinstance(self.free_capacity_gb, six.string_types)
and self.free_capacity_gb != 'unknown'):
raise exception.InvalidCapacity(
name='free_capacity_gb',
value=six.text_type(self.free_capacity_gb)
)
if self.free_capacity_gb != 'unknown':
self.free_capacity_gb -= share['size']
self.updated = timeutils.utcnow()
def __repr__(self):
return ("host: '%(host)s', free_capacity_gb: %(free)s, "
"pools: %(pools)s" % {'host': self.host,
'free': self.free_capacity_gb,
'pools': self.pools}
)
class PoolState(HostState):
def __init__(self, host, capabilities, pool_name):
new_host = share_utils.append_host(host, pool_name)
super(PoolState, self).__init__(new_host, capabilities)
self.pool_name = pool_name
# No pools in pool
self.pools = None
def update_from_share_capability(self, capability, service=None):
"""Update information about a pool from its share_node info."""
self.update_capabilities(capability, service)
if capability:
if self.updated and self.updated > capability['timestamp']:
return
self.update_backend(capability)
self.total_capacity_gb = capability['total_capacity_gb']
self.free_capacity_gb = capability['free_capacity_gb']
self.allocated_capacity_gb = capability.get(
'allocated_capacity_gb', 0)
self.QoS_support = capability.get('QoS_support', False)
self.reserved_percentage = capability['reserved_percentage']
# NOTE(xyang): provisioned_capacity_gb is the apparent total
# capacity of all the shares created on a backend, which is
# greater than or equal to allocated_capacity_gb, which is the
# apparent total capacity of all the shares created on a backend
# in Manila. Using allocated_capacity_gb as the default of
# provisioned_capacity_gb if it is not set.
self.provisioned_capacity_gb = capability.get(
'provisioned_capacity_gb', self.allocated_capacity_gb)
self.max_over_subscription_ratio = capability.get(
'max_over_subscription_ratio',
CONF.max_over_subscription_ratio)
self.thin_provisioning = capability.get(
'thin_provisioning', False)
self.dedupe = capability.get(
'dedupe', False)
self.compression = capability.get(
'compression', False)
def update_pools(self, capability):
# Do nothing, since we don't have pools within pool, yet
pass
class HostManager(object):
"""Base HostManager class."""
host_state_cls = HostState
def __init__(self):
self.service_states = {} # { <host>: {<service>: {cap k : v}}}
self.host_state_map = {}
self.filter_handler = base_host_filter.HostFilterHandler(
'manila.scheduler.filters')
self.filter_classes = self.filter_handler.get_all_classes()
self.weight_handler = base_host_weigher.HostWeightHandler(
'manila.scheduler.weighers')
self.weight_classes = self.weight_handler.get_all_classes()
def _choose_host_filters(self, filter_cls_names):
"""Choose acceptable filters.
Since the caller may specify which filters to use we need to
have an authoritative list of what is permissible. This
function checks the filter names against a predefined set of
acceptable filters.
"""
if filter_cls_names is None:
filter_cls_names = CONF.scheduler_default_filters
if not isinstance(filter_cls_names, (list, tuple)):
filter_cls_names = [filter_cls_names]
good_filters = []
bad_filters = []
for filter_name in filter_cls_names:
found_class = False
for cls in self.filter_classes:
if cls.__name__ == filter_name:
found_class = True
good_filters.append(cls)
break
if not found_class:
bad_filters.append(filter_name)
if bad_filters:
msg = ", ".join(bad_filters)
raise exception.SchedulerHostFilterNotFound(filter_name=msg)
return good_filters
def _choose_host_weighers(self, weight_cls_names):
"""Choose acceptable weighers.
Since the caller may specify which weighers to use, we need to
have an authoritative list of what is permissible. This
function checks the weigher names against a predefined set of
acceptable weighers.
"""
if weight_cls_names is None:
weight_cls_names = CONF.scheduler_default_weighers
if not isinstance(weight_cls_names, (list, tuple)):
weight_cls_names = [weight_cls_names]
good_weighers = []
bad_weighers = []
for weigher_name in weight_cls_names:
found_class = False
for cls in self.weight_classes:
if cls.__name__ == weigher_name:
good_weighers.append(cls)
found_class = True
break
if not found_class:
bad_weighers.append(weigher_name)
if bad_weighers:
msg = ", ".join(bad_weighers)
raise exception.SchedulerHostWeigherNotFound(weigher_name=msg)
return good_weighers
def get_filtered_hosts(self, hosts, filter_properties,
filter_class_names=None):
"""Filter hosts and return only ones passing all filters."""
filter_classes = self._choose_host_filters(filter_class_names)
return self.filter_handler.get_filtered_objects(filter_classes,
hosts,
filter_properties)
def get_weighed_hosts(self, hosts, weight_properties,
weigher_class_names=None):
"""Weigh the hosts."""
weigher_classes = self._choose_host_weighers(weigher_class_names)
weight_properties['server_pools_mapping'] = {}
for backend, info in self.service_states.items():
weight_properties['server_pools_mapping'].update(
info.get('server_pools_mapping', {}))
return self.weight_handler.get_weighed_objects(weigher_classes,
hosts,
weight_properties)
def update_service_capabilities(self, service_name, host, capabilities):
"""Update the per-service capabilities based on this notification."""
if service_name not in ('share',):
LOG.debug('Ignoring %(service_name)s service update '
'from %(host)s',
{'service_name': service_name, 'host': host})
return
# Copy the capabilities, so we don't modify the original dict
capability_copy = dict(capabilities)
capability_copy["timestamp"] = timeutils.utcnow() # Reported time
self.service_states[host] = capability_copy
LOG.debug("Received %(service_name)s service update from "
"%(host)s: %(cap)s" %
{'service_name': service_name, 'host': host,
'cap': capabilities})
def _update_host_state_map(self, context):
# Get resource usage across the available share nodes:
topic = CONF.share_topic
share_services = db.service_get_all_by_topic(context, topic)
for service in share_services:
host = service['host']
# Warn about down services and remove them from host_state_map
if not utils.service_is_up(service) or service['disabled']:
LOG.warn(_LW("Share service is down. (host: %s)") % host)
if self.host_state_map.pop(host, None):
LOG.info(_LI("Removing non-active host: %s from "
"scheduler cache.") % host)
continue
# Create and register host_state if not in host_state_map
capabilities = self.service_states.get(host, None)
host_state = self.host_state_map.get(host)
if not host_state:
host_state = self.host_state_cls(
host,
capabilities=capabilities,
service=dict(six.iteritems(service)))
self.host_state_map[host] = host_state
# Update capabilities and attributes in host_state
host_state.update_from_share_capability(
capabilities, service=dict(six.iteritems(service)))
def get_all_host_states_share(self, context):
"""Returns a dict of all the hosts the HostManager knows about.
Each of the consumable resources in HostState are
populated with capabilities scheduler received from RPC.
For example:
{'192.168.1.100': HostState(), ...}
"""
self._update_host_state_map(context)
# Build a pool_state map and return that map instead of host_state_map
all_pools = {}
for host, state in self.host_state_map.items():
for key in state.pools:
pool = state.pools[key]
# Use host.pool_name to make sure key is unique
pool_key = '.'.join([host, pool.pool_name])
all_pools[pool_key] = pool
return six.itervalues(all_pools)
def get_pools(self, context, filters=None):
"""Returns a dict of all pools on all hosts HostManager knows about."""
self._update_host_state_map(context)
all_pools = []
for host, host_state in self.host_state_map.items():
for pool in host_state.pools.values():
fully_qualified_pool_name = share_utils.append_host(
host, pool.pool_name)
host_name = share_utils.extract_host(
fully_qualified_pool_name, level='host')
backend_name = share_utils.extract_host(
fully_qualified_pool_name, level='backend').split('@')[1] \
if '@' in fully_qualified_pool_name else None
pool_name = share_utils.extract_host(
fully_qualified_pool_name, level='pool')
new_pool = {
'name': fully_qualified_pool_name,
'host': host_name,
'backend': backend_name,
'pool': pool_name,
'capabilities': pool.capabilities,
}
if self._passes_filters(new_pool, filters):
all_pools.append(new_pool)
return all_pools
def _passes_filters(self, dict_to_check, filter_dict):
"""Applies a set of regex filters to a dictionary.
If no filter keys are supplied, the data passes unfiltered and
the method returns True. Otherwise, each key in the filter
(filter_dict) must be present in the data (dict_to_check)
and the filter values are applied as regex expressions to
the data values. If any of the filter values fail to match
their corresponding data values, the method returns False.
But if all filters match, the method returns True.
"""
if not filter_dict:
return True
for filter_key, filter_value in six.iteritems(filter_dict):
if filter_key not in dict_to_check:
return False
if not re.match(filter_value, dict_to_check.get(filter_key)):
return False
return True