The Signpost

Technology report

MediaWiki problems but good news for Toolserver stability

Caching problems hurt users

The mixture of new CSS and old HTML, or old CSS and new HTML (pictured), caused rendering problems across a large number of wikis this week.

Deployments of MediaWiki 1.21wmf5 caused widespread problems for users across wikis when HTML and CSS updates were temporarily out of synchronisation. On the first wikis targeted for deployment, this was caused by the different cache invalidation rates for HTML (typically one month) and CSS (typically five minutes). The retrospective investigation of the problem highlighted the fact that the test wiki – the WMF's answer to a production environment that individual developers can no longer practically emulate themselves – actually demonstrated the exact problem that would later manifest itself on production wikis. It went unnoticed.

Despite attempts to ensure that future deployments did not cause the same problem, similar symptoms were immediately reported after Monday's deployment to the English Wikipedia. The issue was later identified as a repetition of a malfunction of ResourceLoader cache management dating back months (wikitech-l mailing list).

In unrelated news that generated similar reporting, the German Wikipedia (dewiki) was also briefly broken by a botched deployment of version 5 of the Article Feedback Tool. During its first deployment outside of the English Wikipedia, an oversight meant that the database schema changes supposed to precede the deployment had not been carried out, leaving dewiki users unable to access key pages on the site. The problem led to a review of the guidance given to staff attempting deployments, which was found to be out of date in a number of places.

Business as usual for Toolserver as volunteer admin decides to stay

Appropriately, as WMDE look to put the thorny issue of Toolserver twilight funding behind them, the latest issue of the German-language community quarterly Wikimedium focussed on why the chapter encouraged donations.

In the latest episode of a saga dating back nearly two years, German systems administrator DaB. confirmed that he will not follow through on a previous threat to stop devoting his spare time to keeping the Toolserver up and running (toolserver-l mailing list; see also previous extensive Signpost coverage for context).

DaB., like many others involved with the Wikimedia Deutschland (WMDE)-run Toolserver, is concerned that the web tool and bot hosting facility will be switched off, or more likely simply left to die, before its replacement – Wikimedia Labs – has been fully prepared for the transition. If it is, DaB. argues, tool creators will be forced into attempting difficult transitions, a not unlikely scenario if development work to improve Wikimedia Labs overruns. Tools will necessarily be lost in the process, he has repeatedly warned (also toolserver-l).

As reported last week, the issue came to a head when DaB.'s ultimatum attempt to get WMDE to fund new hardware for the Toolserver to ensure its continued availability came before the chapter's AGM. After much deliberation, the chapter settled on a "wait-and-see" policy that aimed to balance DaB.'s concerns with the realities of the WMF-WMDE relationship. That policy centres on a request for a binding roadmap from the Wikimedia Foundation, accompanied by WMDE's own assurance that all "necessary resources" (notwendigen Mittel) will be made available to ensure the "almost uninterrupted functionality" (annähernd störungsfreie Funktionalität) of the Toolserver. WMDE also agreed to bear the brunt of any attempt by the WMF to withdraw their support-in-kind for the Toolserver, currently valued at $65,000/year. Writing after the AGM, DaB. said that he was "disappointed" and would need time to consider whether the amended motion was sufficient to entice him to stay.

On Monday DaB. announced his decision: he would stay for another twelve months, though he remains unconvinced that the need for a functioning Toolserver will cease any time soon. He cited a number of factors for staying, including a need to continue advocating for financial support and his personal pride in the project. Though the path ahead would be "rocky", he wrote, "the Toolserver and you all are worth my time, the Toolserver is still helpful, and there is always the possibility that WMDE will [make the right decisions]." As of time of writing, DaB. and other involved parties were still struggling to get the Toolserver's set of replicated databases back up to date, a process that requires technical assistance from the WMF.

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.


















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