On production servers, if you frequently find yourself running out of available space in PHP’s app cache, you can increase this value by editing the file below.
$ sudo vim /etc/php/5.6/mods-available/apcu.ini
Add this line to the apcu.ini file, swapping out 512M with the amount of your choice.
apc.shm_size=512M
Finally, stop / start php for changes to take effect. This will dump all existing caches which may put strain on your server if done during production hours.
Check your available app cache
To see how much space you currently have available, go to the /site-admin
page of any Emergence powered site and look at the Used App Cache
and Available App Cache
values.