Wikimedia Technology/Annual Plans/FY2019/TEC4: PHP7 Migration/Goals

=Program Goals and Status for FY18/19=

TEC4 PHP Migration
 * Goal Owners: Mark Bergsma and Ian Marlier
 * Program Goals for FY18/19: At the conclusion of this program, Zend PHP7 will be the only PHP runtime supported or used in the Wikimedia Foundation production environment.
 * Annual Plan: PHP7 Migration
 * Primary Goal is Knowledge as a Service: Evolve our systems and structures
 * Tech Goal: Sustaining



 = Q1 Goals =

Outcome 1 / Output 1.2
Zend PHP7 is the only PHP runtime in use in the WMF environment
 * All wikis, including wikitech/office/etc, are being run under the Zend PHP7 runtime

Dependencies on: Traffic & Performance teams; Primary team: Service Operations

Goal(s)
Allow MediaWiki requests to be served by PHP7 alongside HHVM
 * Install and configure php-fpm alongside HHVM on the application servers
 * Refactor Apache configuration to allow selection of PHP engine based on HTTP request
 * Stretch: Evaluate performance of PHP 7.0, 7.2 versus HHVM, and pick one. ❌
 * Stretch: Refactor the puppet module "mediawiki" classes to role/profile structure

Status
July 2018

August 14, 2018

September 11, 2018
 * This goal is ongoing but slightly behind schedule due to high priority work on the data center switchover, as well as unexpected absence & vacations. It is though expected to complete shortly after EOQ. The stretch goal of evaluating PHP7 performance is currently stalled, as MediaWiki currently still does not pass all tests on PHP7.2

Outcome 1 / Output 1.2
Zend PHP7 is the only PHP runtime in use in the WMF environment
 * All wikis, including wikitech/office/etc, are being run under the Zend PHP7 runtime

Primary teams: Performance & Core Platform

Goal(s)

 * A sampling profiler that works under PHP7 has been identified and is prepared for use in the WMF production environment. If no appropriate profiler can be identified, then a statement of work for contractor effort to build one is prepared.

Status
July 30, 2018

August 2018
 * Somewhat at risk due to Core Platform's other work load, might be at risk for completion this quarter.

September 11, 2018
 * Somewhat at risk due to Core Platform's other work load, might be at risk for completion this quarter.



= Q2 Goals =

Outcome 1 / Output 1.2
Zend PHP7 is the only PHP runtime in use in the WMF environment
 * All wikis, including wikitech/office/etc, are being run under the Zend PHP7 runtime

Dependencies on: Traffic, Performance, Core Platform teams; Primary team: Service Operations

Goal(s)
Ability to serve a % of production traffic from PHP7
 * Separate Traffic layer caches for PHP7/HHVM
 * Allow directing users to PHP7 based on a cookie/header/beta feature
 * Evaluate scalability and performance of php7 compared to HHVM
 * Evaluate PHP 7.0, 7.2 and pick a version to use.
 * Identify and address code issues and opportunities under PHP 7.2

Status
October 2018
 * Discussed...

November 2018
 * Discussed...

December 2018
 * Discussed...