1e1e7a842f
This adds a service plugin to introduce random delays and deadlocks to DB operations to make it easier for us to see that retry decorators are correctly applied and race conditions are handled. Change-Id: I8e283c1b53165faee548d26b3560a2c883dfb977
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1.6 KiB
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39 lines
1.6 KiB
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Licensed under the Apache License, Version 2.0 (the "License"); you may
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not use this file except in compliance with the License. You may obtain
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a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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License for the specific language governing permissions and limitations
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under the License.
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Convention for heading levels in Neutron devref:
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======= Heading 0 (reserved for the title in a document)
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------- Heading 1
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~~~~~~~ Heading 2
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+++++++ Heading 3
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''''''' Heading 4
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(Avoid deeper levels because they do not render well.)
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Transient DB Failure Injection
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==============================
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Neutron has a service plugin to inject random delays and Deadlock exceptions
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into normal Neutron operations. The service plugin is called 'Loki' and is
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located under neutron.services.loki.loki_plugin.
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To enable the plugin, just add 'loki' to the list of service_plugins in your
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neutron-server neutron.conf file.
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The plugin will inject a Deadlock exception on database flushes with a 1/50
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probability and a delay of 1 second with a 1/200 probability when SQLAlchemy
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objects are loaded into the persistent state from the DB. The goal is to ensure
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the code is tolerant of these transient delays/failures that will be experienced
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in busy production (and Galera) systems.
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