There will be PHP7 - Test in Production - Berlin Edition

How we migrated the Wikimedia infrastructure to PHP7 without most of you noticing!

Transcript

1. There Will Be PHP7 Test in Production - Berlin 2019 @manjiki giuseppe lavagetto • effie mouzeli
3. MediaWiki ✺ Our core application ✺ PHP, Apache, MySQL. Yes.* ✺ Thick caching layer ✺ App servers cluster (Web) ✺ API cluster ✺ Jobrunners/Videoscalers cluster MediaWiki is a free server-based software, licensed under the GNU GPL. It is an extremely powerful, scalable software, and a feature-rich wiki implementation that uses PHP to process and display data stored in a database, such as MySQL. 3 * it’s complicated
4. HHVM & PHP-FPM ✺ Hip Hop Virtual Machine (2014) ✴ PHP5 and Hack ✴ JIT ✴ Performant ✺ PHP FastCGI Process Manager (2019) ✴ PHP7 Support ✴ Opcode Caching ✴ Performant HHVM is developed by Facebook and supports only the Hack programming language PHP-FPM is a community project and is PHP-FastCGI implementation with additional features 4 @manjiki
5. Initial Preparations ✺ Install PHP-FPM ✺ Introduce PHP7 cookie ✺ Browser extension ✺ Beta Users 5 ✺ CI ✺ Observability ✺ Cache slotting
6. Initial Preparations ✺ Install PHP-FPM ✺ Introduce PHP7 cookie ✺ Browser extension ✺ Beta Users 6 ✺ CI ✺ Observability ✺ Cache slotting
7. Rolling out
8. Rolling out: Appservers ✺ 43 servers ✺ Control percentage of anon users getting the PHP7 cookie ✺ Pushed to ~20% ✺ Not all users accept cookies 8 Issue: Opcache corruptions :( @manjiki
9. Rolling out: API servers ✺ 47 Servers ✺ A few API clients supported cookies ✺ Introduced php7_only feature flag ✺ Converted servers to PHP7 ✴ Each server serves ~2% of API traffic 9 Issue: This actually went well!
10. Rolling out: Jobrunners ✺ 24 Servers ✺ Catalogued jobs ✺ Migrated high traffic jobs ✺ Migrated lower traffic ones ✺ Enabled php7_only on all 10 Issue: This actually went well! @manjiki
11. Finish Line
12. Test encyclopaedias in prod? https://jobs.wikimedia.org https://grafana.wikimedia.org/ https://github.com/wikimedia/operations-puppet https://phabricator.wikimedia.org/ https://wikitech.wikimedia.org/ Test in Production - Berlin 2019 @manjiki