In November of last year, Aaron noticed a spike in memcached traffic, which
we were eventually able to attribute to Wikibase client fetching the
SiteList on every request. When Katie fixed it, outbound memcached traffic
nearly halved.
We're now back to the same rate of outbound traffic as then, and the
culprit appears to be the same key.
See:
http://i.imgur.com/v9ebld6.png
Tracked in
https://bugzilla.wikimedia.org/show_bug.cgi?id=56602
