No memory cache configured error after installing and configuring memcached

Nextcloud version: 15.0.12
Operating system and version:: Ubuntu 18.04
Apache or nginx version: 2.4.29
PHP version: 7.2.19-0ubuntu0.18.04.2
Memcached Version: 3.0.1
libmemcached version: 1.0.18

I’m going through clearing out Security & setup warnings and got to:

  • No memory cache has been configured. To enhance performance, please configure a memcache, if available. Further information can be found in the documentation.

So I installed memcached and configured it, double checked it was running:

memcached.service - memcached daemon
   Loaded: loaded (/lib/systemd/system/memcached.service; enabled; vendor preset: enabled)
   Active: active (running) since Thu 2019-09-26 21:31:52 PDT; 3min 15s ago
     Docs: man:memcached(1)
 Main PID: 15159 (memcached)
    Tasks: 10 (limit: 4915)
   CGroup: /system.slice/memcached.service
           └─15159 /usr/bin/memcached -m 256 -p 11211 -u memcache -l -P /var/run/memcached/

Sep 26 21:31:52 ENCOM systemd[1]: Started memcached daemon.

And then configured it in config.php following the directions:

'memcache.distributed' => '\\OC\\Memcache\\Memcached',
  'memcached_servers' => array(
        // hostname, port and optional weight. Also see:
        array('localhost', 11211),
        //array('', 11211),
  'memcached_options' => array(
        // Set timeouts to 50ms
        \Memcached::OPT_CONNECT_TIMEOUT => 50,
        \Memcached::OPT_RETRY_TIMEOUT =>   50,
        \Memcached::OPT_SEND_TIMEOUT =>    50,
        \Memcached::OPT_RECV_TIMEOUT =>    50,
        \Memcached::OPT_POLL_TIMEOUT =>    50,

        // Enable compression
        \Memcached::OPT_COMPRESSION =>          true,

        // Turn on consistent hashing
        \Memcached::OPT_LIBKETAMA_COMPATIBLE => true,

        // Enable Binary Protocol
        \Memcached::OPT_BINARY_PROTOCOL =>      true,


I’ve restarted apache and memecached, but still I get the error.

What am I doing wrong?