On 26 January 2012 21:53, Sumana Harihareswara <sumanah(a)wikimedia.org>wrote;wrote:
On 01/26/2012 04:45 PM, Chad wrote:
On Thu, Jan 26, 2012 at 4:31 PM, MZMcBride
<z(a)mzmcbride.com> wrote:
> What's this about "taking your site down for maintenance"? I don't
think
> Wikimedia wikis have needed to go into read-only mode or go offline(!)
for
> an upgrade since like MediaWiki 1.5 or
something. I skimmed
> <https://www.mediawiki.org/wiki/MediaWiki_1.19> and didn't see any
crazy
database
schema changes or anything. Am I missing something?
Not that I can see, there's no major schema changes this go
round so I can't see any reason we'd need to go offline/readonly.
-Chad
OK. I was under the impression that we announce these windows partly
because if something goes very wrong during the upgrade, sites might go
offline or readonly. Is that wrong or inapplicable here? Perhaps
better wording would instead just talk about possible JS breakage or
some other, more likely ill effects? Let me know and I'll send a
followup mail.
The risk of a new software bug sending a wiki offline is about the same
during a
version update as for any other individual update: more changes
are being pushed, but more testing has been done on them. Breakages can
almost always be remedied by rolling back the deployment, especially now we
have the het-deploy framework in good working order, and the more serious
the breakage, the faster it will be noticed. Updates leaving the sites
readable but readonly are pretty implausible, and a breakage leaving a site
offline for a substantial period of time pretty unlikely. I'd say
scheduling around 250 sets of national events against such remote
eventualities is substantial overkill.
--HM