Invalidate opcache after theme / plugin updates

[seebeen]

Depending on the server opcache configuration, there is a high possibility of getting an Internal Server Error, or similar after updating a plugin / theme.

Specific opchache settings I've verified that trigger the error are:

[opcache]
opcache.enable=1
opcache.enable_cli=1
opcache.memory_consumption=256
opcache.interned_strings_buffer=24
opcache.max_accelerated_files=130987
opcache.max_wasted_percentage=2
opcache.use_cwd=1
opcache.validate_timestamps=1
opcache.revalidate_freq=5
opcache.revalidate_path=0
opcache.save_comments=1
opcache.enable_file_override=1

Error happens because validate_timestamps is set to 1 and revalidate_freq is greater than 0. This means that after plugin update, error 500 will stay for up to revalidate_freq seconds due to invalid opcache.

This can be mitigated by adding a opcache_invalidate or opcache_reset call upon successful update.

[seebeen]

P.S. I'm willing to make a PR and work on the bug.

[swissspidy]

Hi there and welcome to WordPress Trac!

Is this happening with manual updates on Dashboard -> Updates or when uploading a new ZIP file? Some steps to reproduce would be helpful.

In most places core uses its own move_dir() function which already does OPcache invalidation. See wp_opcache_invalidate_directory() and wp_opcache_invalidate(). So this kind of issue shouldn't be happening. But if there's a place where this was forgotten, the more info we have the better.

[seebeen]

Happening on the following places:

• Manual plugin updates via plugin list admin page
• Manual plugin updates via updates admin page
• WP CLI

I've narrowed it down even further.
Exact combination of opcache settings is:

[opcache]
opcache.enabla=1
opcache.use_cwd=1
opcache.enable_file_override=1
opcache.validate_timestamps=1
opcache.revalidate_freq=5
opcache.revalidate_path=0

Any number greateer than 0 will work for revalidate_freq

You can reproduce the bug I'm getting by setting these settings, updating a plugin and once you see a success notice, reload the admin page -> bam error 500.