Opcache issue: opcache.file_cache_callback (or documentation issue?)

Hello togehter, many people seem to have problems with opcache on windows. https://bugs.php.net/bug.php?id=70022 http://stackoverflow.com/questions/35908029/zend-opcache-issue-windows-server-2012-iis-plesk-php-7 https://github.com/zendtech/ZendOptimizerPlus/issues/167 My message currently was: Base address marks unusable memory region. Please setup opcache.file_cache and opcache.file_cache_callback directives for more convenient Opcache usage Attempt to access invalid address. I found the "opcache.file_cache" option and set it to, which seem to fixed my problem for now. But what is the option "opcache.file_cache_callback"? I found this option only there https://github.com/php/php-src/blob/3d3f11ede4cc7c83d64cc5edaae7c29ce9c6986f/ext/opcache/shared_alloc_win32.c#L189 Best regards Martin