Last modified: 2014-11-04 12:37:48 UTC
There are a few edit filters which look at new pages, and two types of new pages that they often want to ignore are disambiguation pages, and redirect pages. Detecting disambiguation pages is especially computationally difficult on English wikipedia as we have many templates on [[MediaWiki:Disambiguationspage]].
Examples include [[Special:AbuseFilter/98]], [[Special:AbuseFilter/394]] & [[Special:AbuseFilter/402]]
page_is_redirect is already computed.
Disambiguations are easier for the backend to compute.
Bug 19455 is another way to find disambiguation pages as we could look for [[Category:All_article_disambiguation_pages]].
I think the page [[MediaWiki:Disambiguationspage]] is not needed anymore since [[mw:Extension:Disambiguator]] was deployed to WMF wikis and maybe that extension makes it easier to solve this bug.