How to configure memcache properly in moodle?

Question

Test performance defines the plugin as Invalid.

Answer 1

Just to follow up on question, altough its a bit old, but maybe somebody will stumble upon this: U have to have installed memcached server on OS (Ubuntu: apt install memcached) and correctly configured, you have to have install php extension of memcached (apt install php-memcached) and in my instance, I also had to install php-memcache (without d) for things to work (no idea why tho).

After that, plugin becomes available. Then you have to define mapping for each Known cache definitions and of course configure store instances.