Since WordPress forums deleted my solution for this particular issue, I might as well post it here since I want to help the WordPress and CyberPanel communities.
I have searched the Internet, forums, and bulletin boards, but no one has had a solution that would actually fix it. The fix was just to disable JIT. I have over 200 WordPress installations, and disabling JIT is not an option since I am obsessed with speed. My clients demand performance. I have proof that JIT lowers CPU load on my AMD EPYC servers.
The fix is for WordPress 6.9.4 and 7.0-RC2-62197 running on PHP 8.5.3 and 8.2, 8.3, 8.4, with JIT enabled and tracing. We all love HOT paths; functions are for the others. HOT paths are what make JIT incredibly fast, especially when clients add like 50 plugins.
Root cause: PHP JIT tracing builds a corrupted hot path through get_stylesheet() in wp-includes/theme.php over thousands of requests. After 15-18 hours, the corrupted trace produces a -1 value interpreted as an unsigned 32-bit, resulting in a 4,295,229,440 byte allocation request. This is a PHP JIT compiler bug (not 100% sure), not a WordPress or theme issue.
Verified fix keeps JIT running without crashing:
Add to your PHP php.ini:
opcache.blacklist_filename=/etc/php-jit-blacklist.txt
Create or whatever your hosting path is /etc/php-jit-blacklist.txt:
/home/*/public_html/wp-includes/theme.php
Adjust path prefix to match your server layout.
What this does:
Removes theme.php from JIT compilation while keeping JIT active for all other files. The corrupted trace never builds. The crash may or may not happen, depending on your setup(feedback would be helpful).
Verified against: PHP 8.2, 8.3, 8.5, and some Valkey 9.0.3 with MariaDB 11.8, LiteSpeed LSPHP on about 200 WordPress installs, 10M page views, 1200+ hours crash-free after previously crashing every 15-18 hours without fail.
Turning off JIT entirely also works, but is unnecessary unless you like quitting(looking at the WordPress forum).
My goal was performance, helping the community, and MWA.
Please do your own DD, ask me questions, challenge this assumption, 4295229440 bytes, question everything.
Let me know if you have any questions or need help.