When trying to upgrade nextcloud, I get the following error
www-data@mail:/www/nextcloud$ php7.3 occ upgrade An unhandled exception has been thrown: OC\HintException: [0]: Memcache \OC\Memcache\APCu not available for local cache (Is the matching PHP module installed and enabled?) www-data@mail:/www/nextcloud$
To fix this, you need to install APC cache.
apt install php7.3-apcu
For CLI, you need to edit PHP configuration file
vi /etc/php/7.2/cli/php.ini
at the end of the file, add
apc.enable_cli = 1
You can also enable apc for the current command with option
php7.3 -d apc.enable_cli=1 occ upgrade
