Wikipedia:Wikipedia Signpost/2013-04-01/Technology report

English Wikipedia and other Wikidata deployments likely to be delayed
As previewed in last week's "Technology Report", users of ten Wikipedias including Italian and Russian – in total accounting for some 10% of all visits to Wikimedia sites – this week got access to phase 2 of Wikidata following its first rollout to production wikis (Wikimedia Deutschland blog).

The primary focus of this second phase is the introduction of a new  parser function. The function retrieves a named property of a given Wikidata item (at time of writing, that item must be the one linked to the current page). Thus, using  will retrieve the "CEO" property attached to the current page, if any. The team behind Wikidata reports that they are close to deploying the code necessary to allow editors to use the alternative syntax, as well as allowing them to retrieve properties of arbitrary items (the population of Paris on the article for the Eiffel Tower, for example).

Although the 27 March rollout initially appeared to be wholly a success, WMF Site Architect Asher Feldman quickly raised serious concerns about its impact on site performance. In particular, in a post to the WMF Operations mailing list, he judged two serious "jobqueue related" site outages on 28 March to be the fault, in part, of the ramping up of Wikidata. In both cases, Wikidata's change propagation mechanism had added large numbers of jobs to the jobqueue, a part of Wikipedia site maintenance widely acknowledged to be creaking around the edges. Under the strain, the under-performing job queue caused all WMF slave databases to lag, Feldman noted, ultimately causing the downtime for editors.

"The good thing is," Feldman added "the jobqueue was identified as a scaling bottleneck a while ago, and will be [upgraded] very soon." In the meantime, the Wikidata team report they are also working to limit the pressure Wikidata places on the jobqueue. They hope to avoid performance questions delaying the further rollout of Wikidata phase 2 to other client wikis (including the English Wikipedia) over the next month.

In related news, WMF Editor Engagement specialist Steven Walling gave his concerns about the Wikidata implementation currently being rolled out and, in particular, the difficulty new users will have in working out where property values can be changed (answer: the item page on wikidata.org). The problem might be solved in the short term with the addition of overt " [edit] " links and in the longer term via integration with the VisualEditor, it was suggested.

In brief
Not all fixes may have gone live to WMF sites at the time of writing; some may not be scheduled to go live for several weeks.
 * Make wikitech.wikimedia.org "developer hub", says co-ordinator: WMF Technical Contributor Coordinator Quim Gil has suggested a radical shaking up of the series of wikis devoted to developer support, most notably centralising information into two wikis. The first, MediaWiki.org, would be trimmed down to content aimed at MediaWiki reusers, including installation instructions. The second, wikitech.wikimedia.org, would be beefed up from its current form by receiving documentation relating to developer support. In this way, it would become a "developer hub", Gil wrote, covering "API, reference docs, howtos, tutorials... including bots, gadgets and templates", making it easier for new or more casual contributors to get involved. A related proposal would leverage Semantic MediaWiki and its extensions to provide "nodes" (mockup pictured right) on wikitech.wikimedia.org. In an admission that the Groups framework he founded earlier late last year (see previous Signpost coverage) had not proved successful, these nodes would help create informal groupings around common interests, Gil argued. Criticism of the proposals has so far centred on the extent to which a division between "user" and "developer" is possible when so many users are developers and so many features needed by both (e.g. API documentation).
 * The "Special:ActiveUsers" page was removed due to performance concerns, and a thread was started on mediawiki-l about it.