def get_cost_functions(self, topic=None):
"""Returns a list of tuples containing weights and cost functions to
use for weighing hosts
"""
if topic is None:
# Schedulers only support compute right now.
topic = "compute"
if topic in self.cost_function_cache:
return self.cost_function_cache[topic]
cost_fns = []
for cost_fn_str in FLAGS.least_cost_functions:
if '.' in cost_fn_str:
short_name = cost_fn_str.split('.')[-1]
else:
short_name = cost_fn_str
cost_fn_str = "%s.%s.%s" % (__name__, self.__class__.__name__,
short_name)
if not (short_name.startswith('%s_' % topic)
or short_name.startswith('noop')):
continue
try:
# NOTE: import_class is somewhat misnamed since
# the weighing function can be any non-class callable
# (i.e., no 'self')
cost_fn = importutils.import_class(cost_fn_str)
except ImportError:
raise exception.SchedulerCostFunctionNotFound(
cost_fn_str=cost_fn_str)
try:
flag_name = "%s_weight" % cost_fn.__name__
weight = getattr(FLAGS, flag_name)
except AttributeError:
raise exception.SchedulerWeightFlagNotFound(
flag_name=flag_name)
cost_fns.append((weight, cost_fn))
self.cost_function_cache[topic] = cost_fns
return cost_fns
def _get_cost_functions():
"""Returns a list of tuples containing weights and cost functions to
use for weighing hosts
"""
cost_fns_conf = CONF.least_cost_functions
if cost_fns_conf is None:
# The old default. This will get fixed up below.
fn_str = 'nova.scheduler.least_cost.compute_fill_first_cost_fn'
cost_fns_conf = [fn_str]
cost_fns = []
for cost_fn_str in cost_fns_conf:
short_name = cost_fn_str.split('.')[-1]
if not (short_name.startswith('compute_')
or short_name.startswith('noop')):
continue
# Fix up any old paths to the new paths
if cost_fn_str.startswith('nova.scheduler.least_cost.'):
cost_fn_str = ('nova.scheduler.weights.least_cost' +
cost_fn_str[25:])
try:
# NOTE: import_class is somewhat misnamed since
# the weighing function can be any non-class callable
# (i.e., no 'self')
cost_fn = importutils.import_class(cost_fn_str)
except ImportError:
raise exception.SchedulerCostFunctionNotFound(
cost_fn_str=cost_fn_str)
try:
flag_name = "%s_weight" % cost_fn.__name__
weight = getattr(CONF, flag_name)
except AttributeError:
raise exception.SchedulerWeightFlagNotFound(flag_name=flag_name)
# Set the original default.
if (flag_name == 'compute_fill_first_cost_fn_weight'
and weight is None):
weight = -1.0
cost_fns.append((weight, cost_fn))
return cost_fns
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 '.' in cost_fn_str:
short_name = cost_fn_str.split('.')[-1]
else:
short_name = cost_fn_str
cost_fn_str = "%s.%s.%s" % (__name__, self.__class__.__name__,
short_name)
if not (short_name.startswith('%s_' % topic)
or short_name.startswith('noop')):
continue
try:
# NOTE(sirp): import_class is somewhat misnamed since it can
# any callable from a module
cost_fn = utils.import_class(cost_fn_str)
except exception.ClassNotFound:
raise exception.SchedulerCostFunctionNotFound(
cost_fn_str=cost_fn_str)
try:
weight = getattr(FLAGS, "%s_weight" % cost_fn.__name__)
except AttributeError:
raise exception.SchedulerWeightFlagNotFound(
flag_name=flag_name)
cost_fns.append((weight, cost_fn))
self.cost_fns_cache[topic] = cost_fns
return cost_fns
