753689 - sync: Test and deploy MySQL option READ COMMITTED

Status: RESOLVED WONTFIX

(Cloud Services :: Operations: Deployment Requests - DEPRECATED, task)

Description

[:Atoll]

+++ This bug was initially created as a clone of Bug #694222 +++

Separating bug 694222 into two pieces.

READ_COMMITTED is this bug, innodb_locks_unsafe_for_binlog=ON is bug 694222.

Comment 1

[:Atoll]

We pushed some % of servers in production with READ_UNCOMMITTED, rather than READ_COMMITTED.  So, next steps:

* Load test R_C in stage
* Ship config to production
* Schedule a ChangeWindow

ChangeWindow is a WIP at https://services.etherpad.mozilla.org/27

Comment 2

[:Atoll]

r37257 = baf736b055c3d6715e31d9272f55a0901c47ed88 (refs/remotes/git-svn)
    switch sync stage mysql from READ-UNCOMMITTED to READ-COMMITTED

-transaction-isolation=READ-UNCOMMITTED
+transaction-isolation=READ-COMMITTED

Restarted MySQL on sync{1..8}.db.scl2.stage.svc. Confirmed expected configuration is in place.

$ xapply -P8 "ssh %1 'sudo mysql -NBe \"show global variables\"' | egrep '(innodb_support_xa|innodb_locks_unsafe_for_binlog|tx_isolation)'" sync{1..8}.db.scl2.stage.svc.mozilla.com | sort -u
innodb_locks_unsafe_for_binlog	ON
innodb_support_xa	OFF
tx_isolation	READ-COMMITTED

Ready for load test.

Comment 3

[Chris Kolosiwsky [:ckolos] (ckolos has left the building)]

:bobm...