https://office.wikimedia.org/wiki/Health_check_survey_results/FY2014-15_Q3 indicates a growing concern about code review. Our code review queues keep growing, I'd say still faster than our concerns, and this trend can only lead to some variation of *collapse*.
http://korma.wmflabs.org/browser/gerrit_review_queue.html shows these monthly snapshots of open chagesets waiting for review (-1 and work in progress are not counted):
- May 2013: 250
- May 2014: 1033
- May 2015: 1549
In order to stop this trend, revert it, and clean our queues we need a radical change.
Any actions must be coordinated with the migration from Gerrit to Differential in T114311.
The current situation is the result of a combination of problems. Let's identify them, creating an own task when appropriate:
- Prioritization / weak open source culture: more pressure to write new code than to review patches contributed.
- Unmaintained repositories: lack of owners is a problem, lack of disclaimers for potential contributors to these repos too. (T102920)
- Volunteers having a hard time getting their contributions reviewed, also in active repos (T78768)
- Lack of sync between developer teams: team A stuck because team B doesn't review their patches.
- Our code review practices are not common across reviewers and don't focus on efficiency (T101686#1355049)
- Our Continuous Integration tooling could be better at catching trivial errors or code style issues (T101686#1355049)
- MediaWiki core, a case on its own: biggest project, unclear ownership, not all maintainers can review all areas.
- Noise in metrics: dozens of basically unmaintained repositories containing 1-2 very old patches make difficult to dig into the really problematic repositories. See also T102112; T102920
- Poor quality of patches: require a lot of effort to push forward, making reviewers to pass instead of review with -1.
- ... ?
- Gerrit review queue metrics (includes a ranking of repositories), but cf. T110520
- 100 Oldest open changesets without code review + Open changesets with most activity
- Most active Gerrit users (# actions) and top reviewers (exercising +2/-2)
Potential approaches and solutions
See preliminary results at https://www.mediawiki.org/wiki/User:AKlapper_%28WMF%29/Code_Review