Building upon the RedisLockingStrategy we have implemented a locking strategy that works with redis replication. If you are interested, I'll submit a PR.

There should be a destructor in RedisLockStrategy.php to release the lock otherwise it takes the full ttl time until lock is released (maybe not in every case, i encounter this issue with redirects).

    /**
     * Destructor:
     * Releases lock automatically when instance is destroyed and release resources
     */
    public function __destruct()
    {
        $this->release();
    }

According to the TYPO3 v8 LTS documentation https://api.typo3.org/typo3cms/8/html/interface_t_y_p_o3_1_1_c_m_s_1_1_core_1_1_locking_1_1_locking_strategy_interface.html#a09d8a107b07d88279198923eb92a8737
this function called without arguments should acquire an exclusive lock. If the lock is acquired by another process, it should block (wait) until the lock is released by that process, acquire the lock and return. In fact, this function as implemented does nothing of that but does return in (nearly) every case the boolean value TRUE, what makes the whole locker unnecessary.