cinder/cinder/scheduler/weights/__init__.py
Ben Swartzlander de66e8f811 Add stochastic weight handler to scheduler
Add a config option to the scheduler host manager to select host
weight managers other than the default. Rename the existing default
weight manager TopHostWeightHandler because its behavior is to
always choose the top weight. Add a new weight manager which
randomly chooses the host using weights as probabilities.

DocImpact

Implements blueprint stochastic-weighing-scheduler

Change-Id: Ie5985066e68aef25600f8b76948adacd4c04263a
2016-08-02 20:16:01 +00:00

46 lines
1.3 KiB
Python

# Copyright (c) 2011 OpenStack Foundation.
# 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.
"""
Scheduler host weights
"""
from cinder.scheduler import base_weight
class WeighedHost(base_weight.WeighedObject):
def to_dict(self):
return {
'weight': self.weight,
'host': self.obj.host,
}
def __repr__(self):
return ("WeighedHost [host: %s, weight: %s]" %
(self.obj.host, self.weight))
class BaseHostWeigher(base_weight.BaseWeigher):
"""Base class for host weights."""
pass
class OrderedHostWeightHandler(base_weight.BaseWeightHandler):
object_class = WeighedHost
def __init__(self, namespace):
super(OrderedHostWeightHandler, self).__init__(BaseHostWeigher,
namespace)