Wikimedia Technical Operations/ICU announcement/en

Update to ICU Unicode library
Starting on April 9th we'll migrate the servers running the MediaWiki application servers to a new release of the ICU Unicode library (International Components for Unicode) (from version 52 to 57).

This migration will cause some unavoidable temporary user-visible impact: The sorting of some category pages will be distorted – all pages which have been updated with the new software version will use the new sorting while untouched pages still use the old sorting. As such, we need to run a maintenance script to update the sorting for old entries.

The distortions may last from a few hours (on medium-sized wikis), up to a day (on the largest wikis), and a few days on English Wikipedia. The start-time will depend upon when the migration script reaches each wiki.

This affects a number of large wikis (including eight out of the ten biggest Wikipedias). The detailed list and the task for the technical implementation is at T189295.

Thank you.