62 lines
2.4 KiB
Python
62 lines
2.4 KiB
Python
# Copyright (c) 2014 Cisco Systems Inc.
|
|
# 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.
|
|
|
|
from oslo_config import cfg
|
|
from oslo_log import log as logging
|
|
|
|
from nova_solverscheduler.scheduler.solvers import constraints
|
|
|
|
CONF = cfg.CONF
|
|
CONF.import_opt("max_instances_per_host",
|
|
"nova.scheduler.filters.num_instances_filter")
|
|
|
|
LOG = logging.getLogger(__name__)
|
|
|
|
|
|
class NumInstancesConstraint(constraints.BaseLinearConstraint):
|
|
"""Constraint that specifies the maximum number of instances that
|
|
each host can launch.
|
|
"""
|
|
|
|
def _get_max_instances_per_host(self, host_state, filter_properties):
|
|
return CONF.max_instances_per_host
|
|
|
|
def get_constraint_matrix(self, hosts, filter_properties):
|
|
num_hosts = len(hosts)
|
|
num_instances = filter_properties.get('num_instances')
|
|
|
|
constraint_matrix = [[True for j in xrange(num_instances)]
|
|
for i in xrange(num_hosts)]
|
|
|
|
for i in xrange(num_hosts):
|
|
max_instances = self._get_max_instances_per_host(hosts[i],
|
|
filter_properties)
|
|
num_host_instances = hosts[i].num_instances
|
|
acceptable_num_instances = int(max_instances - num_host_instances)
|
|
if acceptable_num_instances < 0:
|
|
acceptable_num_instances = 0
|
|
if acceptable_num_instances < num_instances:
|
|
inacceptable_num = num_instances - acceptable_num_instances
|
|
constraint_matrix[i] = (
|
|
[True for j in xrange(acceptable_num_instances)] +
|
|
[False for j in xrange(inacceptable_num)])
|
|
|
|
LOG.debug("%(host)s can accept %(num)s requested instances "
|
|
"according to NumInstancesConstraint.",
|
|
{'host': hosts[i],
|
|
'num': acceptable_num_instances})
|
|
|
|
return constraint_matrix
|