When enabling OPcache via Ploi, Ploi will automatically set the memory consumption variable to use 512MB. At some point, you might want to increase this limit as your number of sites grow.
Luckily, changing this via Ploi is rather easy. First head over to your server and visit the PHP tab. Next press the menu button for the PHP version you'd like to change and select "Edit FPM".
A modal will open with the PHP configuration, you can use CTRL + F or CMD + F to search inside this file and search for opcache preferably. You will see a variable called memory_consumption, feel free to change this to a number to your liking. Make sure to not go over your available RAM.
After you've changed your OPcache memory consumption, make sure to reload the FPM worker by either restarting or reloading it.