masakari-monitors/masakarimonitors/introspectiveinstancemonitor/cache.py
Louie KWAN a680e323b8 Introspective Instance Monitoring through QEMU Guest Agent
https://blueprints.launchpad.net/masakari/+spec/introspective-instance-monitoring

Currently, Masakari instance monitoring is strictly black-box
type monitoring through qemu and libvirt. There are however a number of
internal instance/VM faults, that if monitored and detected by Masakari,
could be recovered by existing Masakari auto-recovery mechanisms; increasing
the overall availability of the instance/VM. This blueprint introduces the
capability of performing introspective instance monitoring of VMs, in order
to detect, report and optionally recover VMs from internal VM faults.
Specifically, VM Heartbeating Monitoring via the QEMU Guest Agent.

Change-Id: I9efc6afc8d476003d3aa7fee8c31bcaa65438674
Implements: blueprint introspective-instance-monitoring
2018-07-12 14:02:34 +00:00

124 lines
5.0 KiB
Python

# Copyright (c) 2018 WindRiver Systems
#
# 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.
"""
The code related to integration between oslo.cache module and masakarimonitors.
Use 'oslo_cache.dict'
i.e. dogpile.cache backend that uses dictionary for storage
Dogpile consists of two subsystems, one building on top of the other.
dogpile provides the concept of a dogpile lock, a control structure
which allows a single thread of execution to be selected as the creator
of some resource, while allowing other threads of execution to refer
to the previous version of this resource as the creation proceeds;
if there is no previous version, then those threads block until
the object is available.
"""
from oslo_cache import core
from oslo_config import cfg
from masakarimonitors.i18n import _
WEEK = 604800
def register_cache_configurations(conf):
"""Register all configurations required for oslo.cache.
The procedure registers all configurations required for oslo.cache.
It should be called before configuring of cache region
:param conf: instance of configuration
:returns: updated configuration
"""
# register global configurations for caching
core.configure(conf)
# register specific configurations
constraint_cache_group = cfg.OptGroup('constraint_validation_cache')
constraint_cache_opts = [
cfg.IntOpt('expiration_time', default=WEEK,
help=_(
'TTL, in seconds, for any cached item in the '
'dogpile.cache region used for caching of validation '
'constraints.')),
cfg.BoolOpt("caching", default=True,
help=_(
'Toggle to enable/disable caching when Orchestration '
'Engine validates property constraints of stack.'
'During property validation with constraints '
'Orchestration Engine caches requests to other '
'OpenStack services. Please note that the global '
'toggle for oslo.cache(enabled=True in [cache] group) '
'must be enabled to use this feature.'))
]
conf.register_group(constraint_cache_group)
conf.register_opts(constraint_cache_opts, group=constraint_cache_group)
extension_cache_group = cfg.OptGroup('service_extension_cache')
extension_cache_opts = [
cfg.IntOpt('expiration_time', default=WEEK,
help=_(
'TTL, in seconds, for any cached item in the '
'dogpile.cache region used for caching of service '
'extensions.')),
cfg.BoolOpt('caching', default=True,
help=_(
'Toggle to enable/disable caching when Orchestration '
'Engine retrieves extensions from other OpenStack '
'services. Please note that the global toggle for '
'oslo.cache(enabled=True in [cache] group) must be '
'enabled to use this feature.'))
]
conf.register_group(extension_cache_group)
conf.register_opts(extension_cache_opts, group=extension_cache_group)
find_cache_group = cfg.OptGroup('resource_finder_cache')
find_cache_opts = [
cfg.IntOpt('expiration_time', default=WEEK,
help=_(
'TTL, in seconds, for any cached item in the '
'dogpile.cache region used for caching of OpenStack '
'service finder functions.')),
cfg.BoolOpt('caching', default=True,
help=_(
'Toggle to enable/disable caching when Orchestration '
'Engine looks for other OpenStack service resources '
'using name or id. Please note that the global '
'toggle for oslo.cache(enabled=True in [cache] group) '
'must be enabled to use this feature.'))
]
conf.register_group(find_cache_group)
conf.register_opts(find_cache_opts, group=find_cache_group)
return conf
# variable that stores an initialized cache region
_REGION = None
def get_cache_region():
global _REGION
if not _REGION:
_REGION = core.create_region()
_REGION.configure('oslo_cache.dict',
arguments={'expiration_time': WEEK})
core.configure_cache_region(
conf=register_cache_configurations(cfg.CONF),
region=_REGION)
return _REGION