Installing and upgrading help

We had problems with Redis and session locking handling. We have faced the same problems with memcached too:

[28-Feb-2018 18:12:32 Europe/Berlin] Cannot obtain session lock for sid: e9g9mt3294u0grq5ft4adr124h within 120. It is likely another page has a long session lock, or the session lock was never released.

[28-Feb-2018 18:12:32 Europe/Berlin] Default exception handler: error/Unable to obtain session lock Debug:

Error code: Unable to obtain session lock

$a contents:

* line 366 of /lib/classes/session/redis.php: core\session\exception thrown

* line 258 of /lib/classes/session/redis.php: call to core\session\redis->lock_session()

* line ? of unknownfile: call to core\session\redis->handler_read()

* line 42 of /lib/classes/session/handler.php: call to session_start()

* line 124 of /lib/classes/session/redis.php: call to core\session\handler->start()

* line 77 of /lib/classes/session/manager.php: call to core\session\redis->start()

* line 785 of /lib/setup.php: call to core\session\manager::start()

* line 45 of /config.php: call to require_once()

* line 5 of /course/view.php: call to require_once()

Our configuration is as follows:

#$CFG->session_handler_class = '\core\session\redis';

#$CFG->session_redis_host = 'XXXXX';

#$CFG->session_redis_port = 6379;  // Optional.

#$CFG->session_redis_database = 0;  // Optional, default is db 0.

#$CFG->session_redis_prefix = $CFG->dbname.'.sess.key.'; // Optional, default is don't set one.

#$CFG->session_redis_acquire_lock_timeout = 120;

#$CFG->session_redis_lock_expire = 7200;

#$CFG->session_redis_serializer_use_igbinary = true;

Are you experiencing these problems with memcached or Redis too?

Thank you very much in advance