Please copy this to your local village pump or other relevant on-wiki forum.
Werdna's #ifexist limit feature is now live. In response to complaints of
template breakage, I have increased the limit on Wikimedia wikis
temporarily, from 100 to 2000. Barring a coup, it will stay at 2000 for
about a week, and then we'll lower it to 100.
Please use this one-week period to check pages and templates that use
#ifexist heavily. Look in the HTML source of the preview or page view.
There will be a "limit report" that looks like this:
<!--
Pre-expand include size: 617515/2048000 bytes
Post-expand include size: 360530/2048000 bytes
Template argument size: 51168/2048000 bytes
#ifexist count: 1887/2000
-->
This is the limit report from
http://commons.wikimedia.org/wiki/Template:Potd/2007-12 ,
one of the pages that will break.
At the end of the week, any pages which have a #ifexist count of over 100
will cease to be rendered correctly (after the next edit or cache clear).
All #ifexist calls after the hundredth will be treated as if the target
does not exist.
In some cases it may be possible to rewrite your templates so that they
still do the same thing, but with less #ifexist calls. In other cases, you
will need to remove template features. Removing features is always sad, as
a sofware developer I know that, but sometimes it is necessary for the
good of the project. This is one of those times.
-- Tim Starling