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Please help me to understand where is difference between APC and APCu lies. While inspecting CentOS web-server (set up not by me) found that it has APCu 4.0.2 installed and phpinfo(); reports that APC Emulated. It was bit confusing, anyway tried to use settings for normal APC in php.ini

apc.shm_size = 768M                       
apc.cache_by_default = 0                  
apc.stat = 0 

Then checked apc.php status page and it revealed that only apc.shm_size changed, but no cache entries for selected domains. So how can i adapt APCu to cache selected domains as APC did ?

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up vote 2 down vote accepted

Since version 5.5, PHP comes with the Zend OpCache engine that substitutes APC. APC had two parts. The APC opcache that is no longer used and is instead emulated in php 5.5, and the APC cache that you can use to store data. That part is now used through the APCu extension.

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