Hmm interesting. I see instructions on setting up Wordpress with FastCGI but no comments about any impact that would have on plugins. Maybe they just don’t worry about it the same way most Koha folk don’t worry about it hehe.
As I recall, Zend Opcache has various settings to control if and when it will recompile the PHP scripts in caches. Depending on what settings you choose, in a FastCGI environment it can periodically check to see if a script has been updated and update the cache if need be - or, if you choose, never revalidate the cache, in which case you'd need to reload or restart php-fpm after changing code.
Also, WordPress has code that tries to clear opcache. [1, 2]
Regards,
Galen
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