diff --git a/nova/scheduler/host_filter.py b/nova/scheduler/host_filter.py index bd6b266080..818ae4a30f 100644 --- a/nova/scheduler/host_filter.py +++ b/nova/scheduler/host_filter.py @@ -305,8 +305,11 @@ class HostFilterScheduler(zone_aware_scheduler.ZoneAwareScheduler): 'instance_type': } """ - def filter_hosts(self, num, request_spec): + def filter_hosts(self, topic, request_spec, hosts): """Filter the full host list (from the ZoneManager)""" + + if hosts: + return hosts filter_name = request_spec.get('filter', None) host_filter = choose_host_filter(filter_name) @@ -317,8 +320,9 @@ class HostFilterScheduler(zone_aware_scheduler.ZoneAwareScheduler): name, query = host_filter.instance_type_to_filter(instance_type) return host_filter.filter_hosts(self.zone_manager, query) - def weigh_hosts(self, num, request_spec, hosts): + def weigh_hosts(self, topic, request_spec, hosts): """Derived classes must override this method and return a lists of hosts in [{weight, hostname}] format. """ - return [dict(weight=1, hostname=host) for host, caps in hosts] + return [dict(weight=1, hostname=hostname, capabilities=caps) + for hostname, caps in hosts] diff --git a/nova/scheduler/least_cost.py b/nova/scheduler/least_cost.py index 629fe2e42f..72db2fd1b8 100644 --- a/nova/scheduler/least_cost.py +++ b/nova/scheduler/least_cost.py @@ -48,25 +48,36 @@ def noop_cost_fn(host): return 1 -flags.DEFINE_integer('fill_first_cost_fn_weight', 1, +flags.DEFINE_integer('compute_fill_first_cost_fn_weight', 1, 'How much weight to give the fill-first cost function') -def fill_first_cost_fn(host): +def compute_fill_first_cost_fn(host): """Prefer hosts that have less ram available, filter_hosts will exclude hosts that don't have enough ram""" hostname, caps = host - free_mem = caps['compute']['host_memory_free'] + free_mem = caps['host_memory_free'] return free_mem class LeastCostScheduler(zone_aware_scheduler.ZoneAwareScheduler): - def get_cost_fns(self): + def __init__(self, *args, **kwargs): + self.cost_fns_cache = {} + super(LeastCoastScheduler, self).__init__(*args, **kwargs) + + def get_cost_fns(self, topic): """Returns a list of tuples containing weights and cost functions to use for weighing hosts """ + + if topic in self.cost_fns_cache: + return self.cost_fns_cache[topic] + cost_fns = [] for cost_fn_str in FLAGS.least_cost_scheduler_cost_functions: + if not cost_fn_str.startswith('%s_' % topic) and \ + not cost_fn_str.startswith('noop'): + continue try: # NOTE(sirp): import_class is somewhat misnamed since it can @@ -84,23 +95,23 @@ class LeastCostScheduler(zone_aware_scheduler.ZoneAwareScheduler): cost_fns.append((weight, cost_fn)) + self.cost_fns_cache[topic] = cost_fns return cost_fns - def weigh_hosts(self, num, request_spec, hosts): + def weigh_hosts(self, topic, request_spec, hosts): """Returns a list of dictionaries of form: - [ {weight: weight, hostname: hostname} ]""" + [ {weight: weight, hostname: hostname, capabilities: capabs} ] + """ - # FIXME(sirp): weigh_hosts should handle more than just instances - hostnames = [hostname for hostname, caps in hosts] - - cost_fns = self.get_cost_fns() + cost_fns = self.get_cost_fns(topic) costs = weighted_sum(domain=hosts, weighted_fns=cost_fns) weighted = [] weight_log = [] - for cost, hostname in zip(costs, hostnames): + for cost, (hostname, caps) in zip(costs, hosts): weight_log.append("%s: %s" % (hostname, "%.2f" % cost)) - weight_dict = dict(weight=cost, hostname=hostname) + weight_dict = dict(weight=cost, hostname=hostname, + capabilities=caps) weighted.append(weight_dict) LOG.debug(_("Weighted Costs => %s") % weight_log) @@ -127,7 +138,8 @@ def weighted_sum(domain, weighted_fns, normalize=True): weighted_fns - list of weights and functions like: [(weight, objective-functions)] - Returns an unsorted of scores. To pair with hosts do: zip(scores, hosts) + Returns an unsorted list of scores. To pair with hosts do: + zip(scores, hosts) """ # Table of form: # { domain1: [score1, score2, ..., scoreM] @@ -150,7 +162,6 @@ def weighted_sum(domain, weighted_fns, normalize=True): domain_scores = [] for idx in sorted(score_table): elem_score = sum(score_table[idx]) - elem = domain[idx] domain_scores.append(elem_score) return domain_scores diff --git a/nova/scheduler/zone_aware_scheduler.py b/nova/scheduler/zone_aware_scheduler.py index e7bff2faa5..d4d3d04143 100644 --- a/nova/scheduler/zone_aware_scheduler.py +++ b/nova/scheduler/zone_aware_scheduler.py @@ -224,18 +224,34 @@ class ZoneAwareScheduler(driver.Scheduler): raise NotImplemented(_("Zone Aware Scheduler only understands " "Compute nodes (for now)")) - #TODO(sandy): how to infer this from OS API params? - num_instances = 1 + num_instances = request_spec['num_instances'] + instance_type = request_spec['instance_type'] - # Filter local hosts based on requirements ... - host_list = self.filter_hosts(num_instances, request_spec) + weighted = [] + host_list = None - # TODO(sirp): weigh_hosts should also be a function of 'topic' or - # resources, so that we can apply different objective functions to it + for i in xrange(num_instances): + # Filter local hosts based on requirements ... + # + # The first pass through here will pass 'None' as the + # host_list.. which tells the filter to build the full + # list of hosts. + # On a 2nd pass, the filter can modify the host_list with + # any updates it needs to make based on resources that + # may have been consumed from a previous build.. + host_list = self.filter_hosts(topic, request_spec, host_list) + if not host_list: + break - # then weigh the selected hosts. - # weighted = [{weight=weight, name=hostname}, ...] - weighted = self.weigh_hosts(num_instances, request_spec, host_list) + # then weigh the selected hosts. + # weighted = [{weight=weight, hostname=hostname, + # capabilities=capabs}, ...] + weights = self.weigh_hosts(topic, request_spec, host_list) + weights.sort(key=operator.itemgetter('weight')) + best_weight = weights[0] + weighted.append(best_weight) + self.consume_resources(best_weight['capabilities'], + instance_type) # Next, tack on the best weights from the child zones ... json_spec = json.dumps(request_spec) @@ -254,18 +270,58 @@ class ZoneAwareScheduler(driver.Scheduler): weighted.sort(key=operator.itemgetter('weight')) return weighted - def filter_hosts(self, num, request_spec): - """Derived classes must override this method and return - a list of hosts in [(hostname, capability_dict)] format. + def compute_filter(self, hostname, capabilities, request_spec): + """Return whether or not we can schedule to this compute node. + Derived classes should override this and return True if the host + is acceptable for scheduling. """ - # NOTE(sirp): The default logic is the equivalent to AllHostsFilter - service_states = self.zone_manager.service_states - return [(host, services) - for host, services in service_states.iteritems()] + instance_type = request_spec['instance_type'] + reqested_mem = instance_type['memory_mb'] + return capabilities['host_memory_free'] >= requested_mem - def weigh_hosts(self, num, request_spec, hosts): + def filter_hosts(self, topic, request_spec, host_list=None): + """Return a list of hosts which are acceptable for scheduling. + Return value should be a list of (hostname, capability_dict)s. + Derived classes may override this, but may find the + '_filter' function more appropriate. + """ + + def _default_filter(self, hostname, capabilities, request_spec): + """Default filter function if there's no _filter""" + # NOTE(sirp): The default logic is the equivalent to + # AllHostsFilter + return True + + filter_func = getattr(self, '%s_filter' % topic, _default_filter) + + filtered_hosts = [] + if host_list is None: + host_list = self.zone_manager.service_states.iteritems() + for host, services in host_list: + if topic not in services: + continue + if filter_func(host, services['topic'], request_spec): + filtered_hosts.append((host, services['topic'])) + + def weigh_hosts(self, topic, request_spec, hosts): """Derived classes may override this to provide more sophisticated scheduling objectives """ # NOTE(sirp): The default logic is the same as the NoopCostFunction - return [dict(weight=1, hostname=host) for host, caps in hosts] + return [dict(weight=1, hostname=hostname, capabilities=capabilities) + for hostname, capabilities in hosts] + + def compute_consume(self, capabilities, instance_type): + """Consume compute resources for selected host""" + + requested_mem = max(instance_type['memory_mb'], 0) + capabilities['host_memory_free'] -= requested_mem + + def consume_resources(self, topic, capabilities, instance_type): + """Consume resources for a specific host. 'host' is a tuple + of the hostname and the services""" + + consume_func = getattr(self, '%s_consume' % topic, None) + if not consume_func: + return + consume_func(capabilities, instance_type)