47fa88d947
Recently in the gate we have seen a trace on some work-in-progress
patches:
OperationalError: (pymysql.err.OperationalError)
(1040, u'Too many connections')
and at least one operator has reported that the number of database
connections increased significantly going from Mitaka to Newton.
It was suspected that the increase was caused by creating new oslo.db
transaction context managers on-the-fly when switching database
connections for cells. Comparing the dstat --tcp output of runs of the
gate-tempest-dsvm-neutron-full-ubuntu-xenial job with and without
caching of the database connections showed a difference of 445 active
TCP connections and 1495 active TCP connections, respectively [1].
This adds caching of the oslo.db transaction context managers and the
oslo.messaging transports to avoid creating a large number of objects
that are not being garbage-collected as expected.
Closes-Bug: #1691545
[1] https://docs.google.com/spreadsheets/d/1DIfFfX3kaA_SRoCM-aO7BN4IBEShChXLztOBFeKryt4/edit?usp=sharing
Change-Id: I17e0eb836dd87aac5859f506e7d771d42753d31a
Team and repository tags
OpenStack Nova
OpenStack Nova provides a cloud computing fabric controller, supporting a wide variety of compute technologies, including: libvirt (KVM, Xen, LXC and more), Hyper-V, VMware, XenServer and OpenStack Ironic.
OpenStack Nova 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.
API
To learn how to use Nova's API, consult the documentation available online at:
https://developer.openstack.org/api-guide/compute/ https://developer.openstack.org/api-ref/compute/
For more information on OpenStack APIs, SDKs and CLIs, please see:
https://www.openstack.org/appdev/ https://developer.openstack.org/
Operators
To learn how to deploy and configure OpenStack Nova, consult the documentation available online at:
For information about the different compute (hypervisor) drivers supported by Nova, please read:
https://docs.openstack.org/developer/nova/feature_classification.html
In the unfortunate event that bugs are discovered, they should be reported to the appropriate bug tracker. If you obtained the software from a 3rd party operating system vendor, it is often wise to use their own bug tracker for reporting problems. In all other cases use the master OpenStack bug tracker, available at:
Developers
For information on how to contribute to Nova, please see the contents of the CONTRIBUTING.rst.
Any new code must follow the development guidelines detailed in the HACKING.rst file, and pass all unit tests.
Further developer focused documentation is available at: