yahoo-eng-team team mailing list archive

[Doug Hellmann <doug@xxxxxxxxxxxxxxxx>]

** Changed in: oslo.db/juno
       Status: Triaged => Fix Committed

** Changed in: oslo.db/juno
       Status: Fix Committed => Fix Released

-- 
You received this bug notification because you are a member of Yahoo!
Engineering Team, which is subscribed to Keystone.
https://bugs.launchpad.net/bugs/1374497

Title:
  change in oslo.db "ping" handling is causing issues in projects that
  are not using transactions

Status in OpenStack Identity (Keystone):
  Triaged
Status in Oslo Database library:
  Fix Committed
Status in oslo.db juno series:
  Fix Released

Bug description:
  in https://review.openstack.org/#/c/106491/, the "ping" listener which
  emits "SELECT 1" at connection start was moved from being a connection
  pool "checkout" handler to a "transaction on begin" handler.
  Apparently Keystone and possibly others are using the Session in
  "autocommit" mode, despite that this is explicitly warned against in
  SQLAlchemy's docs (see
  http://docs.sqlalchemy.org/en/rel_0_9/orm/session.html#autocommit-
  mode), and for these projects they are seeing failed connections not
  transparently recovered (see
  https://bugs.launchpad.net/keystone/+bug/1361378).

  Alternatives include:

  1. move the ping listener back to being a "checkout" handler

  2. fix downstream projects to not use the session in autocommit mode

  In all likelihood, the fix here should involve both.   I have a longer
  term plan to fix EngineFacade once and for all so that the correct use
  patterns are explicit, but that still has to be blueprinted.

To manage notifications about this bug go to:
https://bugs.launchpad.net/keystone/+bug/1374497/+subscriptions