Adds LeastCostScheduler which uses a series of cost functions and associated weights to determine which host to provision to.
Left for future work: * Handle scheduling of many instances (currently assumes n=1) * Handle scheduling of arbitrary resources (currently weigh_hosts only handles instances) * Add more cost functions (currently just noop and fill-first) * Simulator so we can determine sensible values for cost-function-weights NOTE: This patch depends on Sandy's dist-scheduler-2a patch.
This commit is contained in:
commit
56c3418d53
@ -486,6 +486,15 @@ class SchedulerHostFilterNotFound(NotFound):
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message = _("Scheduler Host Filter %(filter_name)s could not be found.")
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class SchedulerCostFunctionNotFound(NotFound):
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message = _("Scheduler cost function %(cost_fn_str)s could"
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" not be found.")
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class SchedulerWeightFlagNotFound(NotFound):
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message = _("Scheduler weight flag not found: %(flag_name)s")
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class InstanceMetadataNotFound(NotFound):
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message = _("Instance %(instance_id)s has no metadata with "
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"key %(metadata_key)s.")
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@ -41,6 +41,7 @@ import json
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from nova import exception
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from nova import flags
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from nova import log as logging
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from nova.scheduler import zone_aware_scheduler
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from nova import utils
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from nova.scheduler import zone_aware_scheduler
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156
nova/scheduler/least_cost.py
Normal file
156
nova/scheduler/least_cost.py
Normal file
@ -0,0 +1,156 @@
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# Copyright (c) 2011 Openstack, LLC.
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# All Rights Reserved.
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#
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# Licensed under the Apache License, Version 2.0 (the "License"); you may
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# not use this file except in compliance with the License. You may obtain
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# a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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# License for the specific language governing permissions and limitations
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# under the License.
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"""
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Least Cost Scheduler is a mechanism for choosing which host machines to
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provision a set of resources to. The input of the least-cost-scheduler is a
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set of objective-functions, called the 'cost-functions', a weight for each
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cost-function, and a list of candidate hosts (gathered via FilterHosts).
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The cost-function and weights are tabulated, and the host with the least cost
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is then selected for provisioning.
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"""
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import collections
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from nova import flags
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from nova import log as logging
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from nova.scheduler import zone_aware_scheduler
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from nova import utils
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LOG = logging.getLogger('nova.scheduler.least_cost')
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FLAGS = flags.FLAGS
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flags.DEFINE_list('least_cost_scheduler_cost_functions',
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['nova.scheduler.least_cost.noop_cost_fn'],
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'Which cost functions the LeastCostScheduler should use.')
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# TODO(sirp): Once we have enough of these rules, we can break them out into a
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# cost_functions.py file (perhaps in a least_cost_scheduler directory)
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flags.DEFINE_integer('noop_cost_fn_weight', 1,
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'How much weight to give the noop cost function')
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def noop_cost_fn(host):
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"""Return a pre-weight cost of 1 for each host"""
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return 1
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flags.DEFINE_integer('fill_first_cost_fn_weight', 1,
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'How much weight to give the fill-first cost function')
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def fill_first_cost_fn(host):
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"""Prefer hosts that have less ram available, filter_hosts will exclude
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hosts that don't have enough ram"""
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hostname, caps = host
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free_mem = caps['compute']['host_memory_free']
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return free_mem
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class LeastCostScheduler(zone_aware_scheduler.ZoneAwareScheduler):
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def get_cost_fns(self):
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"""Returns a list of tuples containing weights and cost functions to
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use for weighing hosts
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"""
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cost_fns = []
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for cost_fn_str in FLAGS.least_cost_scheduler_cost_functions:
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try:
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# NOTE(sirp): import_class is somewhat misnamed since it can
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# any callable from a module
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cost_fn = utils.import_class(cost_fn_str)
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except exception.ClassNotFound:
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raise exception.SchedulerCostFunctionNotFound(
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cost_fn_str=cost_fn_str)
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try:
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weight = getattr(FLAGS, "%s_weight" % cost_fn.__name__)
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except AttributeError:
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raise exception.SchedulerWeightFlagNotFound(
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flag_name=flag_name)
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cost_fns.append((weight, cost_fn))
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return cost_fns
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def weigh_hosts(self, num, request_spec, hosts):
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"""Returns a list of dictionaries of form:
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[ {weight: weight, hostname: hostname} ]"""
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# FIXME(sirp): weigh_hosts should handle more than just instances
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hostnames = [hostname for hostname, caps in hosts]
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cost_fns = self.get_cost_fns()
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costs = weighted_sum(domain=hosts, weighted_fns=cost_fns)
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weighted = []
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weight_log = []
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for cost, hostname in zip(costs, hostnames):
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weight_log.append("%s: %s" % (hostname, "%.2f" % cost))
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weight_dict = dict(weight=cost, hostname=hostname)
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weighted.append(weight_dict)
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LOG.debug(_("Weighted Costs => %s") % weight_log)
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return weighted
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def normalize_list(L):
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"""Normalize an array of numbers such that each element satisfies:
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0 <= e <= 1"""
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if not L:
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return L
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max_ = max(L)
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if max_ > 0:
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return [(float(e) / max_) for e in L]
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return L
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def weighted_sum(domain, weighted_fns, normalize=True):
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"""Use the weighted-sum method to compute a score for an array of objects.
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Normalize the results of the objective-functions so that the weights are
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meaningful regardless of objective-function's range.
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domain - input to be scored
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weighted_fns - list of weights and functions like:
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[(weight, objective-functions)]
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Returns an unsorted of scores. To pair with hosts do: zip(scores, hosts)
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"""
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# Table of form:
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# { domain1: [score1, score2, ..., scoreM]
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# ...
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# domainN: [score1, score2, ..., scoreM] }
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score_table = collections.defaultdict(list)
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for weight, fn in weighted_fns:
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scores = [fn(elem) for elem in domain]
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if normalize:
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norm_scores = normalize_list(scores)
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else:
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norm_scores = scores
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for idx, score in enumerate(norm_scores):
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weighted_score = score * weight
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score_table[idx].append(weighted_score)
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# Sum rows in table to compute score for each element in domain
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domain_scores = []
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for idx in sorted(score_table):
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elem_score = sum(score_table[idx])
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elem = domain[idx]
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domain_scores.append(elem_score)
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return domain_scores
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@ -39,7 +39,7 @@ class ZoneAwareScheduler(driver.Scheduler):
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return api.call_zone_method(context, method, specs=specs)
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def schedule_run_instance(self, context, instance_id, request_spec,
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*args, **kwargs):
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*args, **kwargs):
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"""This method is called from nova.compute.api to provision
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an instance. However we need to look at the parameters being
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passed in to see if this is a request to:
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@ -116,6 +116,9 @@ class ZoneAwareScheduler(driver.Scheduler):
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# Filter local hosts based on requirements ...
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host_list = self.filter_hosts(num_instances, request_spec)
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# TODO(sirp): weigh_hosts should also be a function of 'topic' or
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# resources, so that we can apply different objective functions to it
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# then weigh the selected hosts.
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# weighted = [{weight=weight, name=hostname}, ...]
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weighted = self.weigh_hosts(num_instances, request_spec, host_list)
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@ -139,12 +142,16 @@ class ZoneAwareScheduler(driver.Scheduler):
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def filter_hosts(self, num, request_spec):
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"""Derived classes must override this method and return
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a list of hosts in [(hostname, capability_dict)] format.
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a list of hosts in [(hostname, capability_dict)] format.
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"""
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raise NotImplemented()
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# NOTE(sirp): The default logic is the equivalent to AllHostsFilter
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service_states = self.zone_manager.service_states
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return [(host, services)
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for host, services in service_states.iteritems()]
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def weigh_hosts(self, num, request_spec, hosts):
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"""Derived classes must override this method and return
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a lists of hosts in [{weight, hostname}] format.
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"""Derived classes may override this to provide more sophisticated
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scheduling objectives
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"""
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raise NotImplemented()
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# NOTE(sirp): The default logic is the same as the NoopCostFunction
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return [dict(weight=1, hostname=host) for host, caps in hosts]
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18
nova/test.py
18
nova/test.py
@ -184,7 +184,7 @@ class TestCase(unittest.TestCase):
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wsgi.Server.start = _wrapped_start
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# Useful assertions
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def assertDictMatch(self, d1, d2):
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def assertDictMatch(self, d1, d2, approx_equal=False, tolerance=0.001):
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"""Assert two dicts are equivalent.
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This is a 'deep' match in the sense that it handles nested
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@ -215,15 +215,26 @@ class TestCase(unittest.TestCase):
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for key in d1keys:
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d1value = d1[key]
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d2value = d2[key]
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try:
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error = abs(float(d1value) - float(d2value))
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within_tolerance = error <= tolerance
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except (ValueError, TypeError):
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# If both values aren't convertable to float, just ignore
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# ValueError if arg is a str, TypeError if it's something else
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# (like None)
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within_tolerance = False
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if hasattr(d1value, 'keys') and hasattr(d2value, 'keys'):
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self.assertDictMatch(d1value, d2value)
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elif 'DONTCARE' in (d1value, d2value):
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continue
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elif approx_equal and within_tolerance:
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continue
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elif d1value != d2value:
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raise_assertion("d1['%(key)s']=%(d1value)s != "
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"d2['%(key)s']=%(d2value)s" % locals())
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def assertDictListMatch(self, L1, L2):
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def assertDictListMatch(self, L1, L2, approx_equal=False, tolerance=0.001):
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"""Assert a list of dicts are equivalent."""
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def raise_assertion(msg):
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L1str = str(L1)
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@ -239,4 +250,5 @@ class TestCase(unittest.TestCase):
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'len(L2)=%(L2count)d' % locals())
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for d1, d2 in zip(L1, L2):
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self.assertDictMatch(d1, d2)
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self.assertDictMatch(d1, d2, approx_equal=approx_equal,
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tolerance=tolerance)
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0
nova/tests/scheduler/__init__.py
Normal file
0
nova/tests/scheduler/__init__.py
Normal file
206
nova/tests/scheduler/test_host_filter.py
Normal file
206
nova/tests/scheduler/test_host_filter.py
Normal file
@ -0,0 +1,206 @@
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# Copyright 2011 OpenStack LLC.
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# All Rights Reserved.
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#
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# Licensed under the Apache License, Version 2.0 (the "License"); you may
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# not use this file except in compliance with the License. You may obtain
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# a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
|
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# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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# License for the specific language governing permissions and limitations
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# under the License.
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"""
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Tests For Scheduler Host Filters.
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"""
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import json
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from nova import exception
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from nova import flags
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from nova import test
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from nova.scheduler import host_filter
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FLAGS = flags.FLAGS
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class FakeZoneManager:
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pass
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class HostFilterTestCase(test.TestCase):
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"""Test case for host filters."""
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def _host_caps(self, multiplier):
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# Returns host capabilities in the following way:
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# host1 = memory:free 10 (100max)
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# disk:available 100 (1000max)
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# hostN = memory:free 10 + 10N
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# disk:available 100 + 100N
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# in other words: hostN has more resources than host0
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# which means ... don't go above 10 hosts.
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return {'host_name-description': 'XenServer %s' % multiplier,
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'host_hostname': 'xs-%s' % multiplier,
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'host_memory_total': 100,
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'host_memory_overhead': 10,
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'host_memory_free': 10 + multiplier * 10,
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'host_memory_free-computed': 10 + multiplier * 10,
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'host_other-config': {},
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'host_ip_address': '192.168.1.%d' % (100 + multiplier),
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'host_cpu_info': {},
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'disk_available': 100 + multiplier * 100,
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'disk_total': 1000,
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'disk_used': 0,
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'host_uuid': 'xxx-%d' % multiplier,
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'host_name-label': 'xs-%s' % multiplier}
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def setUp(self):
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self.old_flag = FLAGS.default_host_filter
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FLAGS.default_host_filter = \
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'nova.scheduler.host_filter.AllHostsFilter'
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self.instance_type = dict(name='tiny',
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memory_mb=50,
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vcpus=10,
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local_gb=500,
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flavorid=1,
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swap=500,
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rxtx_quota=30000,
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rxtx_cap=200)
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self.zone_manager = FakeZoneManager()
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states = {}
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for x in xrange(10):
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states['host%02d' % (x + 1)] = {'compute': self._host_caps(x)}
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self.zone_manager.service_states = states
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def tearDown(self):
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FLAGS.default_host_filter = self.old_flag
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|
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def test_choose_filter(self):
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# Test default filter ...
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hf = host_filter.choose_host_filter()
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self.assertEquals(hf._full_name(),
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'nova.scheduler.host_filter.AllHostsFilter')
|
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# Test valid filter ...
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hf = host_filter.choose_host_filter(
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'nova.scheduler.host_filter.InstanceTypeFilter')
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self.assertEquals(hf._full_name(),
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'nova.scheduler.host_filter.InstanceTypeFilter')
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# Test invalid filter ...
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try:
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host_filter.choose_host_filter('does not exist')
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self.fail("Should not find host filter.")
|
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except exception.SchedulerHostFilterNotFound:
|
||||
pass
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|
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def test_all_host_filter(self):
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hf = host_filter.AllHostsFilter()
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||||
cooked = hf.instance_type_to_filter(self.instance_type)
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hosts = hf.filter_hosts(self.zone_manager, cooked)
|
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self.assertEquals(10, len(hosts))
|
||||
for host, capabilities in hosts:
|
||||
self.assertTrue(host.startswith('host'))
|
||||
|
||||
def test_instance_type_filter(self):
|
||||
hf = host_filter.InstanceTypeFilter()
|
||||
# filter all hosts that can support 50 ram and 500 disk
|
||||
name, cooked = hf.instance_type_to_filter(self.instance_type)
|
||||
self.assertEquals('nova.scheduler.host_filter.InstanceTypeFilter',
|
||||
name)
|
||||
hosts = hf.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_filter(self):
|
||||
hf = host_filter.JsonFilter()
|
||||
# filter all hosts that can support 50 ram and 500 disk
|
||||
name, cooked = hf.instance_type_to_filter(self.instance_type)
|
||||
self.assertEquals('nova.scheduler.host_filter.JsonFilter', name)
|
||||
hosts = hf.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 = hf.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',
|
||||
['=', '$compute.host_memory_free', 30],
|
||||
]
|
||||
cooked = json.dumps(raw)
|
||||
hosts = hf.filter_hosts(self.zone_manager, cooked)
|
||||
|
||||
self.assertEquals(9, len(hosts))
|
||||
just_hosts = [host for host, caps in hosts]
|
||||
just_hosts.sort()
|
||||
for index, host in zip([1, 2, 4, 5, 6, 7, 8, 9, 10], just_hosts):
|
||||
self.assertEquals('host%02d' % index, host)
|
||||
|
||||
raw = ['in', '$compute.host_memory_free', 20, 40, 60, 80, 100]
|
||||
cooked = json.dumps(raw)
|
||||
hosts = hf.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:
|
||||
hf.filter_hosts(self.zone_manager, cooked)
|
||||
self.fail("Should give KeyError")
|
||||
except KeyError, e:
|
||||
pass
|
||||
|
||||
self.assertTrue(hf.filter_hosts(self.zone_manager, json.dumps([])))
|
||||
self.assertTrue(hf.filter_hosts(self.zone_manager, json.dumps({})))
|
||||
self.assertTrue(hf.filter_hosts(self.zone_manager, json.dumps(
|
||||
['not', True, False, True, False]
|
||||
)))
|
||||
|
||||
try:
|
||||
hf.filter_hosts(self.zone_manager, json.dumps(
|
||||
'not', True, False, True, False
|
||||
))
|
||||
self.fail("Should give KeyError")
|
||||
except KeyError, e:
|
||||
pass
|
||||
|
||||
self.assertFalse(hf.filter_hosts(self.zone_manager,
|
||||
json.dumps(['=', '$foo', 100])))
|
||||
self.assertFalse(hf.filter_hosts(self.zone_manager,
|
||||
json.dumps(['=', '$.....', 100])))
|
||||
self.assertFalse(hf.filter_hosts(self.zone_manager,
|
||||
json.dumps(
|
||||
['>', ['and', ['or', ['not', ['<', ['>=', ['<=', ['in', ]]]]]]]])))
|
||||
|
||||
self.assertFalse(hf.filter_hosts(self.zone_manager,
|
||||
json.dumps(['=', {}, ['>', '$missing....foo']])))
|
144
nova/tests/scheduler/test_least_cost_scheduler.py
Normal file
144
nova/tests/scheduler/test_least_cost_scheduler.py
Normal file
@ -0,0 +1,144 @@
|
||||
# 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 Least Cost Scheduler
|
||||
"""
|
||||
|
||||
from nova import flags
|
||||
from nova import test
|
||||
from nova.scheduler import least_cost
|
||||
from nova.tests.scheduler import test_zone_aware_scheduler
|
||||
|
||||
MB = 1024 * 1024
|
||||
FLAGS = flags.FLAGS
|
||||
|
||||
|
||||
class FakeHost(object):
|
||||
def __init__(self, host_id, free_ram, io):
|
||||
self.id = host_id
|
||||
self.free_ram = free_ram
|
||||
self.io = io
|
||||
|
||||
|
||||
class WeightedSumTestCase(test.TestCase):
|
||||
def test_empty_domain(self):
|
||||
domain = []
|
||||
weighted_fns = []
|
||||
result = least_cost.weighted_sum(domain, weighted_fns)
|
||||
expected = []
|
||||
self.assertEqual(expected, result)
|
||||
|
||||
def test_basic_costing(self):
|
||||
hosts = [
|
||||
FakeHost(1, 512 * MB, 100),
|
||||
FakeHost(2, 256 * MB, 400),
|
||||
FakeHost(3, 512 * MB, 100)
|
||||
]
|
||||
|
||||
weighted_fns = [
|
||||
(1, lambda h: h.free_ram), # Fill-first, free_ram is a *cost*
|
||||
(2, lambda h: h.io), # Avoid high I/O
|
||||
]
|
||||
|
||||
costs = least_cost.weighted_sum(
|
||||
domain=hosts, weighted_fns=weighted_fns)
|
||||
|
||||
# Each 256 MB unit of free-ram contributes 0.5 points by way of:
|
||||
# cost = weight * (score/max_score) = 1 * (256/512) = 0.5
|
||||
# Each 100 iops of IO adds 0.5 points by way of:
|
||||
# cost = 2 * (100/400) = 2 * 0.25 = 0.5
|
||||
expected = [1.5, 2.5, 1.5]
|
||||
self.assertEqual(expected, costs)
|
||||
|
||||
|
||||
class LeastCostSchedulerTestCase(test.TestCase):
|
||||
def setUp(self):
|
||||
super(LeastCostSchedulerTestCase, self).setUp()
|
||||
|
||||
class FakeZoneManager:
|
||||
pass
|
||||
|
||||
zone_manager = FakeZoneManager()
|
||||
|
||||
states = test_zone_aware_scheduler.fake_zone_manager_service_states(
|
||||
num_hosts=10)
|
||||
zone_manager.service_states = states
|
||||
|
||||
self.sched = least_cost.LeastCostScheduler()
|
||||
self.sched.zone_manager = zone_manager
|
||||
|
||||
def tearDown(self):
|
||||
super(LeastCostSchedulerTestCase, self).tearDown()
|
||||
|
||||
def assertWeights(self, expected, num, request_spec, hosts):
|
||||
weighted = self.sched.weigh_hosts(num, request_spec, hosts)
|
||||
self.assertDictListMatch(weighted, expected, approx_equal=True)
|
||||
|
||||
def test_no_hosts(self):
|
||||
num = 1
|
||||
request_spec = {}
|
||||
hosts = []
|
||||
|
||||
expected = []
|
||||
self.assertWeights(expected, num, request_spec, hosts)
|
||||
|
||||
def test_noop_cost_fn(self):
|
||||
FLAGS.least_cost_scheduler_cost_functions = [
|
||||
'nova.scheduler.least_cost.noop_cost_fn'
|
||||
]
|
||||
FLAGS.noop_cost_fn_weight = 1
|
||||
|
||||
num = 1
|
||||
request_spec = {}
|
||||
hosts = self.sched.filter_hosts(num, request_spec)
|
||||
|
||||
expected = [dict(weight=1, hostname=hostname)
|
||||
for hostname, caps in hosts]
|
||||
self.assertWeights(expected, num, request_spec, hosts)
|
||||
|
||||
def test_cost_fn_weights(self):
|
||||
FLAGS.least_cost_scheduler_cost_functions = [
|
||||
'nova.scheduler.least_cost.noop_cost_fn'
|
||||
]
|
||||
FLAGS.noop_cost_fn_weight = 2
|
||||
|
||||
num = 1
|
||||
request_spec = {}
|
||||
hosts = self.sched.filter_hosts(num, request_spec)
|
||||
|
||||
expected = [dict(weight=2, hostname=hostname)
|
||||
for hostname, caps in hosts]
|
||||
self.assertWeights(expected, num, request_spec, hosts)
|
||||
|
||||
def test_fill_first_cost_fn(self):
|
||||
FLAGS.least_cost_scheduler_cost_functions = [
|
||||
'nova.scheduler.least_cost.fill_first_cost_fn'
|
||||
]
|
||||
FLAGS.fill_first_cost_fn_weight = 1
|
||||
|
||||
num = 1
|
||||
request_spec = {}
|
||||
hosts = self.sched.filter_hosts(num, request_spec)
|
||||
|
||||
expected = []
|
||||
for idx, (hostname, caps) in enumerate(hosts):
|
||||
# Costs are normalized so over 10 hosts, each host with increasing
|
||||
# free ram will cost 1/N more. Since the lowest cost host has some
|
||||
# free ram, we add in the 1/N for the base_cost
|
||||
weight = 0.1 + (0.1 * idx)
|
||||
weight_dict = dict(weight=weight, hostname=hostname)
|
||||
expected.append(weight_dict)
|
||||
|
||||
self.assertWeights(expected, num, request_spec, hosts)
|
@ -61,7 +61,8 @@ class SchedulerTestCase(test.TestCase):
|
||||
"""Test case for scheduler"""
|
||||
def setUp(self):
|
||||
super(SchedulerTestCase, self).setUp()
|
||||
self.flags(scheduler_driver='nova.tests.test_scheduler.TestDriver')
|
||||
driver = 'nova.tests.scheduler.test_scheduler.TestDriver'
|
||||
self.flags(scheduler_driver=driver)
|
||||
|
||||
def _create_compute_service(self):
|
||||
"""Create compute-manager(ComputeNode and Service record)."""
|
@ -22,6 +22,37 @@ from nova.scheduler import zone_aware_scheduler
|
||||
from nova.scheduler import zone_manager
|
||||
|
||||
|
||||
def _host_caps(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,
|
||||
'host_memory_overhead': 10,
|
||||
'host_memory_free': 10 + multiplier * 10,
|
||||
'host_memory_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,
|
||||
'disk_total': 1000,
|
||||
'disk_used': 0,
|
||||
'host_uuid': 'xxx-%d' % multiplier,
|
||||
'host_name-label': 'xs-%s' % multiplier}
|
||||
|
||||
|
||||
def fake_zone_manager_service_states(num_hosts):
|
||||
states = {}
|
||||
for x in xrange(num_hosts):
|
||||
states['host%02d' % (x + 1)] = {'compute': _host_caps(x)}
|
||||
return states
|
||||
|
||||
|
||||
class FakeZoneAwareScheduler(zone_aware_scheduler.ZoneAwareScheduler):
|
||||
def filter_hosts(self, num, specs):
|
||||
# NOTE(sirp): this is returning [(hostname, services)]
|
Loading…
Reference in New Issue
Block a user