mahara-contributors team mailing list archive

[Mahara Bot <1514608@xxxxxxxxxxxxxxxxxx>]

Reviewed:  https://reviews.mahara.org/5775
Committed: https://git.mahara.org/mahara/mahara/commit/6ded76ccdd402cd2bf55f465f92a76a8e8add43a
Submitter: Robert Lyon (robertl@xxxxxxxxxxxxxxx)
Branch:    15.04_STABLE

commit 6ded76ccdd402cd2bf55f465f92a76a8e8add43a
Author: Aaron Wells <aaronw@xxxxxxxxxxxxxxx>
Date:   Tue Nov 17 11:20:54 2015 +1300

Disable transactions in MySQL (Bug 1514608)

Mahara's usage of transactions has been causing
major deadlock issues in MySQL with InnoDB.
The immediate fix is to disable them.

behatnotneeded: Covered by existing tests

Change-Id: I2c7e6424e2d58502acd26fdd5d05c797e4ee5eac
(cherry picked from commit e52be8a3135c19b2ed306a5e16fdc0101d756f6d)

-- 
You received this bug notification because you are a member of Mahara
Contributors, which is subscribed to Mahara.
Matching subscriptions: Subscription for all Mahara Contributors -- please ask on #mahara-dev or mahara.org forum before editing or unsubscribing it!
https://bugs.launchpad.net/bugs/1514608

Title:
  MySQL deadlock issues with simultaneous users

Status in Mahara:
  Fix Committed
Status in Mahara 1.10 series:
  Fix Committed
Status in Mahara 15.04 series:
  Fix Committed
Status in Mahara 15.10 series:
  Fix Committed
Status in Mahara 16.04 series:
  Fix Committed

Bug description:
  The patch in Bug 1492919 resolved the deadlock issues for some users,
  but others are still reporting that they are getting deadlocks. This
  seems to be an issue unique to MySQL, and it can happen with as few as
  2 or 3 concurrent users.

  It has been reported across all stable versions. Strangely, it seems
  to be a relatively recent issue (i.e. we never heard this with Mahara
  1.8 or 1.7, etc), so this suggests it was triggered by something that
  changed fairly recently. One possible candidate is our switch to the
  mysqli driver (before that Mahara wasn't doing transactions at all, in
  mysql).

  See also:
  * https://mahara.org/interaction/forum/topic.php?id=7309
  * https://mahara.org/interaction/forum/topic.php?id=7432

To manage notifications about this bug go to:
https://bugs.launchpad.net/mahara/+bug/1514608/+subscriptions