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By Jarry1250 and Aude

MediaWiki 1.17 deployed to sites; initial strife

After the attempted deployments of MediaWiki 1.17 on 8 February 2011, which were quickly reverted on performance grounds (cf. Signpost coverage), the latest edition was deployed once more to Wikimedia sites on February 16. Although a number of relatively significant problems soon appeared, these were regarded as fixable without the need for a retreat to 1.16 (Wikimedia Techblog). There was only a partial recurrence of the load spikes seen with the previous attempts at deployment.

The anecdotal evidence coming from users is that page loading times have indeed been reduced by the new ResourceLoader as hoped. However, many of the issues wikis are now facing were also related to this change: as expected, it broke a number of JavaScript gadgets, including popular scripts such as Twinkle. Although these issues were soon fixed, users were also riled by a bug with the Vector-style edit toolbar when it was re-enabled for editors who had previously tried to turn it off. On this issue, developer Roan Kattouw said that he "apologized for messing up" and explained that the temporary loss of this preference setting was the lesser of two evils. "There are about 4,200 affected users on English Wikipedia, if memory serves," he added (Technical Village Pump).

Other issues were equally temporary. For example, the new stricter SVG parser refused to accept a number of images it had previously allowed, resulting in a loss of thumbnails. Some were soon fixed with a change to the parser (being incorrectly failed); others still need to be fixed manually as they have invalid syntax which results in discrepancies between web browsers, and, in the worst case, security holes. A change in the color of the "New messages" box from orange to blue (cf. Signpost coverage), was soon reverted locally on the English Wikipedia and several other wikis; the change, which was supposed to make the box visually more similar to the Vector skin, may still be reverted globally.

Developer Rob Lanphier explained where the development team was going to go from here:

Developer attention turn to 1.18

With the deployment to WMF wikis of MediaWiki 1.17, developer attentions have begun to turn towards the strategy for MediaWiki 1.18. Mark Hershberger, developer and interim bugmeister (cf. Signpost coverage), outlined his views on where MediaWiki development should go from here (Wikitech-l mailing list):

The issue has been a hot topic in recent months (cf. Signpost coverage from October 2010: 1, 2) and this week proved no exception. Discussions included a debate of the merits of Subversion as the best version control software to be used, and whether a Mozilla-style system (where all developers submit patches, rather than adding their changes to the global codebase immediately) might be a better step. Developer Roan Kattouw expanded on Mark Hershberger's more modest proposal:

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 many weeks.

Early on Saturday, 19 February 2011, bugmeister Mark Hershberger posted a list on wikitech-l of critical bugs to work on over the weekend and fix before a MediaWiki 1.17 tarball is released.

Load on 4 servers cut in half

P.Copp reported bug #27302, a ResourceLoader bug that attached a timestamp to site JS and CSS (e.g. MediaWiki:Common.js), even if these were empty, and attached timestamps to user JS and CSS, thus bypassing the caches, even if a user is logged out and does not have user JS or CSS. Developer Roan Kattouw fixed (r82219 and r82468) the bug, and with the fix, cut load to the 4 Apache servers serving ResourceLoader in half. [1]

Other bug fixes

Over the weekend, the following other bugs were fixed:

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  • I took the liberty of editing the section about how server load was cut in half to reflect the reality that only 4 servers had their load cut in half, not all of our 100+ Apaches as the wording suggested --Catrope (talk) 19:17, 22 February 2011 (UTC)[reply]



       

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