[wp-trac] [WordPress Trac] #63026: Investigate potential performance regressions when using PHP 8.4

[WordPress Trac]

#63026: Investigate potential performance regressions when using PHP 8.4
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 Reporter:  desrosj        |       Owner:  (none)
     Type:  defect (bug)   |      Status:  new
 Priority:  normal         |   Milestone:  6.8
Component:  Database       |     Version:
 Severity:  normal         |  Resolution:
 Keywords:  needs-testing  |     Focuses:  performance
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Changes (by desrosj):

 * milestone:  Awaiting Review => 6.8


Comment:

 Some additional context. There was a
 [https://wordpress.slack.com/archives/C08D0Q6BHNY/p1740590291554779 brief
 conversation in Slack around this] where build tool specific issues were
 mostly ruled out.

 I've also gone and created a PR that runs the performance tests using PHP
 8.4, and it seems to confirm that there is a [https://github.com/WordPress
 /wordpress-develop/actions/runs/13549791988#summary-37871201258 1-5%
 decrease in nearly all metrics across the board]. I also tried using MySQL
 9.2 and the results were more mixed (he majority of metrics declined,
 though not by as much).

 For the short term, I am going to change the timeout value for the PHPUnit
 workflows when 8.4 is being tested to prevent cancellations. The
 conservative timeout value did it's job here and helped us find a
 performance problem! 🙌

 I'm also going to milestone this for 6.8 for investigation purposes. If
 there's nothing actionable prior to RC1, we can punt and continue
 exploring for 6.9.

-- 
Ticket URL: <https://core.trac.wordpress.org/ticket/63026#comment:1>
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