To use the new separate backward compatibility extension, you must load apcu.so first, then apc.so.
extension=apcu.so
extension=apc.so
apc.enabled=1
apc.shm_size=256M
apc.ttl=7200
apc.enable_cli=1
apc.gc_ttl=3600
apc.entries_hint=4096
apc.slam_defense=1
apc.serializer=php
See: krakjoe/apcu#137 (comment)
To use the new separate backward compatibility extension, you must load apcu.so first, then apc.so.
See: krakjoe/apcu#137 (comment)