78f1c7b128
If a Health Manager is overloaded, it can begin to fall very far behind in processing health updates. This causes huge delays in the whole system and can cause two distinctly different issues: 1) If the HMs are all suddenly busy, delays can be long enough that no messages get through within the failover timeout, and amps start to fail, increasing load on the HMs and causing a cascade failure (I have witnessed this happen once and take down over 50 LBs before manual intervention could be taken).. 2) Even one overloaded HM can cause updates to queue for extremely long periods, which makes the system unreliable. Amps can go down and still have health updates register for some time as the HM processes the queue (in some cases I have seen dead amps updated for 5-10 minutes). If we short-circuit handling before we update the health table, we can solve these problems in two ways: 1) The heavy processing generally happens after this, so short-circuiting early will let some other threads finish faster and have some chance of success. 2) Amphora health won't continue to be updated long after the messages were received, so it won't be possible for zombie amphorae to eat as many brains. Change-Id: Iceeacfdcaebe1f9bb99bc08e318c9da73a66898d (cherry picked from commit 61e0c14f48130d1d0519fa5527d2712ba6ce504f)
Team and repository tags
Octavia
Octavia is an operator-grade open source scalable load balancer for use in large OpenStack deployments. It delivers load balancing services on amphorae and provides centralized command and control. Octavia is currently the reference backend for Neutron LBaaS. In the near future, Octavia is likely to become the standard OpenStack LBaaS API endpoint.
Octavia is distributed under the terms of the Apache License, Version 2.0. The full terms and conditions of this license are detailed in the LICENSE file.
Project resources
Developer documentation for the Octavia project is available at https://docs.openstack.org/octavia/latest/
The project source code repository is located at https://git.openstack.org/cgit/openstack/octavia
Project status, bugs, and requests for feature enhancements are tracked on https://launchpad.net/octavia
For more information on project direction and guiding principles for contributors, please see the CONSTITUTION.rst file in this directory, or specifications in the specs/ sub-directory.
The project roadmap is available at https://wiki.openstack.org/wiki/Octavia/Roadmap