41 lines
1.4 KiB
Python
41 lines
1.4 KiB
Python
# vim: tabstop=4 shiftwidth=4 softtabstop=4
|
|
|
|
# Copyright (c) 2010 Openstack, LLC.
|
|
# Copyright 2010 United States Government as represented by the
|
|
# Administrator of the National Aeronautics and Space Administration.
|
|
# 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.
|
|
|
|
"""
|
|
Chance (Random) Scheduler implementation
|
|
"""
|
|
|
|
import random
|
|
|
|
from nova.scheduler import driver
|
|
|
|
|
|
class ChanceScheduler(driver.Scheduler):
|
|
"""Implements Scheduler as a random node selector."""
|
|
|
|
def schedule(self, context, topic, *_args, **_kwargs):
|
|
"""Picks a host that is up at random."""
|
|
|
|
hosts = self.hosts_up(context, topic)
|
|
if not hosts:
|
|
raise driver.NoValidHost(_("Scheduler was unable to locate a host"
|
|
" for this request. Is the appropriate"
|
|
" service running?"))
|
|
return hosts[int(random.random() * len(hosts))]
|