Afert upgrade to Nextcloud Hub 6 (27.1.2) broken transactional locking

Hi.

After upgrade to version Nextcloud Hub 6 (27.1.2), my installation broke trasnactional locking.

Nextcloud version: 27.1.2
Operating system and version: Ubuntu 20.04.6 LTS
Apache or nginx version: Apache/2.4.41 (Ubuntu)
PHP version: 8.1 (mod)

The issue you are facing:

You run upgrade from occ in shell.

Upgrade without issues. But after run web checker, get message:

The database is used for transactional file locking. To enhance performance, please configure memcache, if available.

Is this the first time you’ve seen this error? Y

Config

'memcache.local' => '\\OC\\Memcache\\APCu',
  'filelocking.enabled' => true,
  'memcache.locking' => '\\OC\\Memcache\\Redis',
  'redis' =>
  array (
    'host' => '/var/run/redis/redis-server.sock',
    'port' => 0,
    'password' => '',
    'dbindex' => 0,
  ),

The output of your Nextcloud log in Admin > Logging:

{"reqId":"HHHHHSHHSHSHSHS","level":3,"time":"October 25, 2023 05:02:07","remoteAddr":"81.32.2.33","user":"MYUSER","app":"jsresourceloader","method":"GET","url":"/index.php/settings/user/theming","message":"Could not find resource unsplash/js/user.js to load","userAgent":"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/118.0.0.0 Safari/537.36","version":"27.1.2.1","data":{"app":"jsresourceloader"}}

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):

<?php
$CONFIG = array (
  'instanceid' => 'ociz9efdik2y',
  'passwordsalt' => '+HJKHJHJHHHKHJKHK',
  'secret' => 'jhasdhjkhajkhdkjahjksdhjkhasjkdhkjahsdkhjjkahsd+mGo',
  'trusted_domains' =>
  array (
    0 => 'diwan.mydomain.net',
  ),
  'datadirectory' => '/data',
  'dbtype' => 'mysql',
  'version' => '27.1.2.1',
  'overwrite.cli.url' => 'https://diwan.mydomain.net',
  'dbname' => 'nextcloud',
  'dbhost' => 'localhost',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'mysql.utf8mb4' => true,
  'dbuser' => 'clouduser',
  'dbpassword' => 'jdshkjhaJKSH8Y7',
  'installed' => true,
  'mail_smtpmode' => 'smtp',
  'mail_smtpsecure' => 'tls',
  'mail_sendmailmode' => 'smtp',
  'mail_from_address' => 'sistemas',
  'mail_domain' => 'MYDOMAIN.com',
  'mail_smtpauthtype' => 'PLAIN',
  'mail_smtpauth' => 1,
  'mail_smtphost' => 'smtp.MYDOMAIN.es',
  'mail_smtpport' => '587',
  'mail_smtpname' => 'sistemas@MYDOMAIN.com',
  'mail_smtppassword' => '#/(&sadasjhdahgj',
  'memcache.local' => '\\OC\\Memcache\\APCu',
  'filelocking.enabled' => true,
  'memcache.locking' => '\\OC\\Memcache\\Redis',
  'redis' =>
  array (
    'host' => '/var/run/redis/redis-server.sock',
    'port' => 0,
    'password' => '',
    'dbindex' => 0,
  ),
  'activity_expire_days' => 90,
  'default_phone_region' => 'ES',
  'maintenance' => false,
  'log_type' => 'file',
  'logfile' => '/var/www/nextcloud/nextcloud.log',
  'loglevel' => 3,
  'logdateformat' => 'F d, Y H:i:s',
  'theme' => '',
  'trashbin_retention_obligation' => '1, auto',
  'versions_retention_obligation' => '1, auto',
  'updater.secret' => '$2y$10$CP.78632487932487932478943279234789423897.QzJIs1GAwskkunt23UR28YvutYyhM0u',
);

The output of your Apache/nginx/system log in /var/log/____:
Not show anithing about this issue. Irrelevant

Of course check

root@diwan:/var/www/nextcloud# sudo -u www-data /usr/bin/php8.1 --define apc.enable_cli=1 -m | grep memcache
memcached
root@diwan:/var/www/nextcloud# redis-cli -s /var/run/redis/redis-server.sock ping
PONG