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author | Sandy Walsh <sandy.walsh@rackspace.com> | 2011-05-07 15:36:55 +0000 |
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committer | Tarmac <> | 2011-05-07 15:36:55 +0000 |
commit | 02b97593d0b3ee60ab879e5184be742ef3ac1b64 (patch) | |
tree | 32fcd95b42cd899809c0955ee3e5238c8cdc11bd | |
parent | 621f42274e1fdc2dc0d075c7e7b3508547bb9a96 (diff) | |
parent | a845a769671066a684e38b82c34ded7ded55eed4 (diff) | |
download | nova-02b97593d0b3ee60ab879e5184be742ef3ac1b64.tar.gz nova-02b97593d0b3ee60ab879e5184be742ef3ac1b64.tar.xz nova-02b97593d0b3ee60ab879e5184be742ef3ac1b64.zip |
Host Filtering for Distributed Scheduler (done before weighing)
-rw-r--r-- | nova/exception.py | 5 | ||||
-rw-r--r-- | nova/scheduler/api.py | 8 | ||||
-rw-r--r-- | nova/scheduler/host_filter.py | 288 | ||||
-rw-r--r-- | nova/scheduler/manager.py | 7 | ||||
-rw-r--r-- | nova/scheduler/zone_manager.py | 20 | ||||
-rw-r--r-- | nova/tests/api/openstack/test_zones.py | 2 | ||||
-rw-r--r-- | nova/tests/test_host_filter.py | 208 | ||||
-rw-r--r-- | nova/tests/test_zones.py | 18 |
8 files changed, 523 insertions, 33 deletions
diff --git a/nova/exception.py b/nova/exception.py index 5caad4cf3..9905fb19b 100644 --- a/nova/exception.py +++ b/nova/exception.py @@ -457,6 +457,11 @@ class ZoneNotFound(NotFound): message = _("Zone %(zone_id)s could not be found.") +class SchedulerHostFilterDriverNotFound(NotFound): + message = _("Scheduler Host Filter Driver %(driver_name)s could" + " not be found.") + + class InstanceMetadataNotFound(NotFound): message = _("Instance %(instance_id)s has no metadata with " "key %(metadata_key)s.") diff --git a/nova/scheduler/api.py b/nova/scheduler/api.py index 6bb3bf3cd..816ae5513 100644 --- a/nova/scheduler/api.py +++ b/nova/scheduler/api.py @@ -76,11 +76,9 @@ def zone_update(context, zone_id, data): return db.zone_update(context, zone_id, data) -def get_zone_capabilities(context, service=None): - """Returns a dict of key, value capabilities for this zone, - or for a particular class of services running in this zone.""" - return _call_scheduler('get_zone_capabilities', context=context, - params=dict(service=service)) +def get_zone_capabilities(context): + """Returns a dict of key, value capabilities for this zone.""" + return _call_scheduler('get_zone_capabilities', context=context) def update_service_capabilities(context, service_name, host, capabilities): diff --git a/nova/scheduler/host_filter.py b/nova/scheduler/host_filter.py new file mode 100644 index 000000000..ed8e65c77 --- /dev/null +++ b/nova/scheduler/host_filter.py @@ -0,0 +1,288 @@ +# Copyright (c) 2011 Openstack, LLC. +# 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. + +""" +Host Filter is a driver mechanism for requesting instance resources. +Three drivers are included: AllHosts, Flavor & JSON. AllHosts just +returns the full, unfiltered list of hosts. Flavor is a hard coded +matching mechanism based on flavor criteria and JSON is an ad-hoc +filter grammar. + +Why JSON? The requests for instances may come in through the +REST interface from a user or a parent Zone. +Currently Flavors and/or InstanceTypes are used for +specifing the type of instance desired. Specific Nova users have +noted a need for a more expressive way of specifying instances. +Since we don't want to get into building full DSL this is a simple +form as an example of how this could be done. In reality, most +consumers will use the more rigid filters such as FlavorFilter. + +Note: These are "required" capability filters. These capabilities +used must be present or the host will be excluded. The hosts +returned are then weighed by the Weighted Scheduler. Weights +can take the more esoteric factors into consideration (such as +server affinity and customer separation). +""" + +import json + +from nova import exception +from nova import flags +from nova import log as logging +from nova import utils + +LOG = logging.getLogger('nova.scheduler.host_filter') + +FLAGS = flags.FLAGS +flags.DEFINE_string('default_host_filter_driver', + 'nova.scheduler.host_filter.AllHostsFilter', + 'Which driver to use for filtering hosts.') + + +class HostFilter(object): + """Base class for host filter drivers.""" + + def instance_type_to_filter(self, instance_type): + """Convert instance_type into a filter for most common use-case.""" + raise NotImplementedError() + + def filter_hosts(self, zone_manager, query): + """Return a list of hosts that fulfill the filter.""" + raise NotImplementedError() + + def _full_name(self): + """module.classname of the filter driver""" + return "%s.%s" % (self.__module__, self.__class__.__name__) + + +class AllHostsFilter(HostFilter): + """NOP host filter driver. Returns all hosts in ZoneManager. + This essentially does what the old Scheduler+Chance used + to give us.""" + + def instance_type_to_filter(self, instance_type): + """Return anything to prevent base-class from raising + exception.""" + return (self._full_name(), instance_type) + + def filter_hosts(self, zone_manager, query): + """Return a list of hosts from ZoneManager list.""" + return [(host, services) + for host, services in zone_manager.service_states.iteritems()] + + +class FlavorFilter(HostFilter): + """HostFilter driver hard-coded to work with flavors.""" + + def instance_type_to_filter(self, instance_type): + """Use instance_type to filter hosts.""" + return (self._full_name(), instance_type) + + def filter_hosts(self, zone_manager, query): + """Return a list of hosts that can create instance_type.""" + instance_type = query + selected_hosts = [] + for host, services in zone_manager.service_states.iteritems(): + capabilities = services.get('compute', {}) + host_ram_mb = capabilities['host_memory']['free'] + disk_bytes = capabilities['disk']['available'] + if host_ram_mb >= instance_type['memory_mb'] and \ + disk_bytes >= instance_type['local_gb']: + selected_hosts.append((host, capabilities)) + return selected_hosts + +#host entries (currently) are like: +# {'host_name-description': 'Default install of XenServer', +# 'host_hostname': 'xs-mini', +# 'host_memory': {'total': 8244539392, +# 'overhead': 184225792, +# 'free': 3868327936, +# 'free-computed': 3840843776}, +# 'host_other-config': {}, +# 'host_ip_address': '192.168.1.109', +# 'host_cpu_info': {}, +# 'disk': {'available': 32954957824, +# 'total': 50394562560, +# 'used': 17439604736}, +# 'host_uuid': 'cedb9b39-9388-41df-8891-c5c9a0c0fe5f', +# 'host_name-label': 'xs-mini'} + +# instance_type table has: +#name = Column(String(255), unique=True) +#memory_mb = Column(Integer) +#vcpus = Column(Integer) +#local_gb = Column(Integer) +#flavorid = Column(Integer, unique=True) +#swap = Column(Integer, nullable=False, default=0) +#rxtx_quota = Column(Integer, nullable=False, default=0) +#rxtx_cap = Column(Integer, nullable=False, default=0) + + +class JsonFilter(HostFilter): + """Host Filter driver to allow simple JSON-based grammar for + selecting hosts.""" + + def _equals(self, args): + """First term is == all the other terms.""" + if len(args) < 2: + return False + lhs = args[0] + for rhs in args[1:]: + if lhs != rhs: + return False + return True + + def _less_than(self, args): + """First term is < all the other terms.""" + if len(args) < 2: + return False + lhs = args[0] + for rhs in args[1:]: + if lhs >= rhs: + return False + return True + + def _greater_than(self, args): + """First term is > all the other terms.""" + if len(args) < 2: + return False + lhs = args[0] + for rhs in args[1:]: + if lhs <= rhs: + return False + return True + + def _in(self, args): + """First term is in set of remaining terms""" + if len(args) < 2: + return False + return args[0] in args[1:] + + def _less_than_equal(self, args): + """First term is <= all the other terms.""" + if len(args) < 2: + return False + lhs = args[0] + for rhs in args[1:]: + if lhs > rhs: + return False + return True + + def _greater_than_equal(self, args): + """First term is >= all the other terms.""" + if len(args) < 2: + return False + lhs = args[0] + for rhs in args[1:]: + if lhs < rhs: + return False + return True + + def _not(self, args): + """Flip each of the arguments.""" + if len(args) == 0: + return False + return [not arg for arg in args] + + def _or(self, args): + """True if any arg is True.""" + return True in args + + def _and(self, args): + """True if all args are True.""" + return False not in args + + commands = { + '=': _equals, + '<': _less_than, + '>': _greater_than, + 'in': _in, + '<=': _less_than_equal, + '>=': _greater_than_equal, + 'not': _not, + 'or': _or, + 'and': _and, + } + + def instance_type_to_filter(self, instance_type): + """Convert instance_type into JSON filter object.""" + required_ram = instance_type['memory_mb'] + required_disk = instance_type['local_gb'] + query = ['and', + ['>=', '$compute.host_memory.free', required_ram], + ['>=', '$compute.disk.available', required_disk] + ] + return (self._full_name(), json.dumps(query)) + + def _parse_string(self, string, host, services): + """Strings prefixed with $ are capability lookups in the + form '$service.capability[.subcap*]'""" + if not string: + return None + if string[0] != '$': + return string + + path = string[1:].split('.') + for item in path: + services = services.get(item, None) + if not services: + return None + return services + + def _process_filter(self, zone_manager, query, host, services): + """Recursively parse the query structure.""" + if len(query) == 0: + return True + cmd = query[0] + method = self.commands[cmd] # Let exception fly. + cooked_args = [] + for arg in query[1:]: + if isinstance(arg, list): + arg = self._process_filter(zone_manager, arg, host, services) + elif isinstance(arg, basestring): + arg = self._parse_string(arg, host, services) + if arg != None: + cooked_args.append(arg) + result = method(self, cooked_args) + return result + + def filter_hosts(self, zone_manager, query): + """Return a list of hosts that can fulfill filter.""" + expanded = json.loads(query) + hosts = [] + for host, services in zone_manager.service_states.iteritems(): + r = self._process_filter(zone_manager, expanded, host, services) + if isinstance(r, list): + r = True in r + if r: + hosts.append((host, services)) + return hosts + + +DRIVERS = [AllHostsFilter, FlavorFilter, JsonFilter] + + +def choose_driver(driver_name=None): + """Since the caller may specify which driver to use we need + to have an authoritative list of what is permissible. This + function checks the driver name against a predefined set + of acceptable drivers.""" + + if not driver_name: + driver_name = FLAGS.default_host_filter_driver + for driver in DRIVERS: + if "%s.%s" % (driver.__module__, driver.__name__) == driver_name: + return driver() + raise exception.SchedulerHostFilterDriverNotFound(driver_name=driver_name) diff --git a/nova/scheduler/manager.py b/nova/scheduler/manager.py index 7d62cfc4e..55cd7208b 100644 --- a/nova/scheduler/manager.py +++ b/nova/scheduler/manager.py @@ -60,10 +60,9 @@ class SchedulerManager(manager.Manager): """Get a list of zones from the ZoneManager.""" return self.zone_manager.get_zone_list() - def get_zone_capabilities(self, context=None, service=None): - """Get the normalized set of capabilites for this zone, - or for a particular service.""" - return self.zone_manager.get_zone_capabilities(context, service) + def get_zone_capabilities(self, context=None): + """Get the normalized set of capabilites for this zone.""" + return self.zone_manager.get_zone_capabilities(context) def update_service_capabilities(self, context=None, service_name=None, host=None, capabilities={}): diff --git a/nova/scheduler/zone_manager.py b/nova/scheduler/zone_manager.py index 198f9d4cc..3ddf6f3c3 100644 --- a/nova/scheduler/zone_manager.py +++ b/nova/scheduler/zone_manager.py @@ -106,28 +106,26 @@ class ZoneManager(object): def __init__(self): self.last_zone_db_check = datetime.min self.zone_states = {} # { <zone_id> : ZoneState } - self.service_states = {} # { <service> : { <host> : { cap k : v }}} + self.service_states = {} # { <host> : { <service> : { cap k : v }}} self.green_pool = greenpool.GreenPool() def get_zone_list(self): """Return the list of zones we know about.""" return [zone.to_dict() for zone in self.zone_states.values()] - def get_zone_capabilities(self, context, service=None): + def get_zone_capabilities(self, context): """Roll up all the individual host info to generic 'service' capabilities. Each capability is aggregated into <cap>_min and <cap>_max values.""" - service_dict = self.service_states - if service: - service_dict = {service: self.service_states.get(service, {})} + hosts_dict = self.service_states # TODO(sandy) - be smarter about fabricating this structure. # But it's likely to change once we understand what the Best-Match # code will need better. combined = {} # { <service>_<cap> : (min, max), ... } - for service_name, host_dict in service_dict.iteritems(): - for host, caps_dict in host_dict.iteritems(): - for cap, value in caps_dict.iteritems(): + for host, host_dict in hosts_dict.iteritems(): + for service_name, service_dict in host_dict.iteritems(): + for cap, value in service_dict.iteritems(): key = "%s_%s" % (service_name, cap) min_value, max_value = combined.get(key, (value, value)) min_value = min(min_value, value) @@ -171,6 +169,6 @@ class ZoneManager(object): """Update the per-service capabilities based on this notification.""" logging.debug(_("Received %(service_name)s service update from " "%(host)s: %(capabilities)s") % locals()) - service_caps = self.service_states.get(service_name, {}) - service_caps[host] = capabilities - self.service_states[service_name] = service_caps + service_caps = self.service_states.get(host, {}) + service_caps[service_name] = capabilities + self.service_states[host] = service_caps diff --git a/nova/tests/api/openstack/test_zones.py b/nova/tests/api/openstack/test_zones.py index a3f191aaa..5d5799b59 100644 --- a/nova/tests/api/openstack/test_zones.py +++ b/nova/tests/api/openstack/test_zones.py @@ -75,7 +75,7 @@ def zone_get_all_db(context): ] -def zone_capabilities(method, context, params): +def zone_capabilities(method, context): return dict() diff --git a/nova/tests/test_host_filter.py b/nova/tests/test_host_filter.py new file mode 100644 index 000000000..31e40ae1d --- /dev/null +++ b/nova/tests/test_host_filter.py @@ -0,0 +1,208 @@ +# Copyright 2011 OpenStack LLC. +# 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. +""" +Tests For Scheduler Host Filter Drivers. +""" + +import json + +from nova import exception +from nova import flags +from nova import test +from nova.scheduler import host_filter + +FLAGS = flags.FLAGS + + +class FakeZoneManager: + pass + + +class HostFilterTestCase(test.TestCase): + """Test case for host filter drivers.""" + + def _host_caps(self, multiplier): + # Returns host capabilities in the following way: + # host1 = memory:free 10 (100max) + # disk:available 100 (1000max) + # hostN = memory:free 10 + 10N + # disk:available 100 + 100N + # in other words: hostN has more resources than host0 + # which means ... don't go above 10 hosts. + return {'host_name-description': 'XenServer %s' % multiplier, + 'host_hostname': 'xs-%s' % multiplier, + 'host_memory': {'total': 100, + 'overhead': 10, + 'free': 10 + multiplier * 10, + 'free-computed': 10 + multiplier * 10}, + 'host_other-config': {}, + 'host_ip_address': '192.168.1.%d' % (100 + multiplier), + 'host_cpu_info': {}, + 'disk': {'available': 100 + multiplier * 100, + 'total': 1000, + 'used': 0}, + 'host_uuid': 'xxx-%d' % multiplier, + 'host_name-label': 'xs-%s' % multiplier} + + def setUp(self): + self.old_flag = FLAGS.default_host_filter_driver + FLAGS.default_host_filter_driver = \ + 'nova.scheduler.host_filter.AllHostsFilter' + self.instance_type = dict(name='tiny', + memory_mb=50, + vcpus=10, + local_gb=500, + flavorid=1, + swap=500, + rxtx_quota=30000, + rxtx_cap=200) + + self.zone_manager = FakeZoneManager() + states = {} + for x in xrange(10): + states['host%02d' % (x + 1)] = {'compute': self._host_caps(x)} + self.zone_manager.service_states = states + + def tearDown(self): + FLAGS.default_host_filter_driver = self.old_flag + + def test_choose_driver(self): + # Test default driver ... + driver = host_filter.choose_driver() + self.assertEquals(driver._full_name(), + 'nova.scheduler.host_filter.AllHostsFilter') + # Test valid driver ... + driver = host_filter.choose_driver( + 'nova.scheduler.host_filter.FlavorFilter') + self.assertEquals(driver._full_name(), + 'nova.scheduler.host_filter.FlavorFilter') + # Test invalid driver ... + try: + host_filter.choose_driver('does not exist') + self.fail("Should not find driver") + except exception.SchedulerHostFilterDriverNotFound: + pass + + def test_all_host_driver(self): + driver = host_filter.AllHostsFilter() + cooked = driver.instance_type_to_filter(self.instance_type) + hosts = driver.filter_hosts(self.zone_manager, cooked) + self.assertEquals(10, len(hosts)) + for host, capabilities in hosts: + self.assertTrue(host.startswith('host')) + + def test_flavor_driver(self): + driver = host_filter.FlavorFilter() + # filter all hosts that can support 50 ram and 500 disk + name, cooked = driver.instance_type_to_filter(self.instance_type) + self.assertEquals('nova.scheduler.host_filter.FlavorFilter', name) + hosts = driver.filter_hosts(self.zone_manager, cooked) + self.assertEquals(6, len(hosts)) + just_hosts = [host for host, caps in hosts] + just_hosts.sort() + self.assertEquals('host05', just_hosts[0]) + self.assertEquals('host10', just_hosts[5]) + + def test_json_driver(self): + driver = host_filter.JsonFilter() + # filter all hosts that can support 50 ram and 500 disk + name, cooked = driver.instance_type_to_filter(self.instance_type) + self.assertEquals('nova.scheduler.host_filter.JsonFilter', name) + hosts = driver.filter_hosts(self.zone_manager, cooked) + self.assertEquals(6, len(hosts)) + just_hosts = [host for host, caps in hosts] + just_hosts.sort() + self.assertEquals('host05', just_hosts[0]) + self.assertEquals('host10', just_hosts[5]) + + # Try some custom queries + + raw = ['or', + ['and', + ['<', '$compute.host_memory.free', 30], + ['<', '$compute.disk.available', 300] + ], + ['and', + ['>', '$compute.host_memory.free', 70], + ['>', '$compute.disk.available', 700] + ] + ] + cooked = json.dumps(raw) + hosts = driver.filter_hosts(self.zone_manager, cooked) + + self.assertEquals(5, len(hosts)) + just_hosts = [host for host, caps in hosts] + just_hosts.sort() + for index, host in zip([1, 2, 8, 9, 10], just_hosts): + self.assertEquals('host%02d' % index, host) + + raw = ['not', + ['=', '$compute.host_memory.free', 30], + ] + cooked = json.dumps(raw) + hosts = driver.filter_hosts(self.zone_manager, cooked) + + self.assertEquals(9, len(hosts)) + just_hosts = [host for host, caps in hosts] + just_hosts.sort() + for index, host in zip([1, 2, 4, 5, 6, 7, 8, 9, 10], just_hosts): + self.assertEquals('host%02d' % index, host) + + raw = ['in', '$compute.host_memory.free', 20, 40, 60, 80, 100] + cooked = json.dumps(raw) + hosts = driver.filter_hosts(self.zone_manager, cooked) + + self.assertEquals(5, len(hosts)) + just_hosts = [host for host, caps in hosts] + just_hosts.sort() + for index, host in zip([2, 4, 6, 8, 10], just_hosts): + self.assertEquals('host%02d' % index, host) + + # Try some bogus input ... + raw = ['unknown command', ] + cooked = json.dumps(raw) + try: + driver.filter_hosts(self.zone_manager, cooked) + self.fail("Should give KeyError") + except KeyError, e: + pass + + self.assertTrue(driver.filter_hosts(self.zone_manager, json.dumps([]))) + self.assertTrue(driver.filter_hosts(self.zone_manager, json.dumps({}))) + self.assertTrue(driver.filter_hosts(self.zone_manager, json.dumps( + ['not', True, False, True, False] + ))) + + try: + driver.filter_hosts(self.zone_manager, json.dumps( + 'not', True, False, True, False + )) + self.fail("Should give KeyError") + except KeyError, e: + pass + + self.assertFalse(driver.filter_hosts(self.zone_manager, json.dumps( + ['=', '$foo', 100] + ))) + self.assertFalse(driver.filter_hosts(self.zone_manager, json.dumps( + ['=', '$.....', 100] + ))) + self.assertFalse(driver.filter_hosts(self.zone_manager, json.dumps( + ['>', ['and', ['or', ['not', ['<', ['>=', ['<=', ['in', ]]]]]]]] + ))) + + self.assertFalse(driver.filter_hosts(self.zone_manager, json.dumps( + ['=', {}, ['>', '$missing....foo']] + ))) diff --git a/nova/tests/test_zones.py b/nova/tests/test_zones.py index 688dc704d..e132809dc 100644 --- a/nova/tests/test_zones.py +++ b/nova/tests/test_zones.py @@ -78,38 +78,32 @@ class ZoneManagerTestCase(test.TestCase): def test_service_capabilities(self): zm = zone_manager.ZoneManager() - caps = zm.get_zone_capabilities(self, None) + caps = zm.get_zone_capabilities(None) self.assertEquals(caps, {}) zm.update_service_capabilities("svc1", "host1", dict(a=1, b=2)) - caps = zm.get_zone_capabilities(self, None) + caps = zm.get_zone_capabilities(None) self.assertEquals(caps, dict(svc1_a=(1, 1), svc1_b=(2, 2))) zm.update_service_capabilities("svc1", "host1", dict(a=2, b=3)) - caps = zm.get_zone_capabilities(self, None) + caps = zm.get_zone_capabilities(None) self.assertEquals(caps, dict(svc1_a=(2, 2), svc1_b=(3, 3))) zm.update_service_capabilities("svc1", "host2", dict(a=20, b=30)) - caps = zm.get_zone_capabilities(self, None) + caps = zm.get_zone_capabilities(None) self.assertEquals(caps, dict(svc1_a=(2, 20), svc1_b=(3, 30))) zm.update_service_capabilities("svc10", "host1", dict(a=99, b=99)) - caps = zm.get_zone_capabilities(self, None) + caps = zm.get_zone_capabilities(None) self.assertEquals(caps, dict(svc1_a=(2, 20), svc1_b=(3, 30), svc10_a=(99, 99), svc10_b=(99, 99))) zm.update_service_capabilities("svc1", "host3", dict(c=5)) - caps = zm.get_zone_capabilities(self, None) + caps = zm.get_zone_capabilities(None) self.assertEquals(caps, dict(svc1_a=(2, 20), svc1_b=(3, 30), svc1_c=(5, 5), svc10_a=(99, 99), svc10_b=(99, 99))) - caps = zm.get_zone_capabilities(self, 'svc1') - self.assertEquals(caps, dict(svc1_a=(2, 20), svc1_b=(3, 30), - svc1_c=(5, 5))) - caps = zm.get_zone_capabilities(self, 'svc10') - self.assertEquals(caps, dict(svc10_a=(99, 99), svc10_b=(99, 99))) - def test_refresh_from_db_replace_existing(self): zm = zone_manager.ZoneManager() zone_state = zone_manager.ZoneState() |