From what I understand, the difference between num_cached_keys and num_cached_scripts does not equal the amount of wasted keys.
OPcache Keys are all the relative and absolute paths leading to a script.
So there are naturally more Keys than there are Scripts, the difference here however is not the amount of wasted keys.
https://github.com/PeeHaa/OpCacheGUI/blob/7de269210b596104f6cdf59f897a6a71026f0bf4/src/OpCacheGUI/OpCache/Status.php#L204
From what I understand, the difference between num_cached_keys and num_cached_scripts does not equal the amount of wasted keys. OPcache Keys are all the relative and absolute paths leading to a script. So there are naturally more Keys than there are Scripts, the difference here however is not the amount of wasted keys.
https://image.slidesharecdn.com/yoopeecacheopcacheinternals-140222091502-phpapp02/95/yoopee-cache-op-cache-internals-45-638.jpg?cb=1445541473 https://www.slideshare.net/jpauli/yoopee-cache-op-cache-internals