private function setSplit($key, $value)
    {
        $values = str_split($value, self::VALUE_SPLIT_SIZE);

        $to_set       = array();
        $to_set[$key] = self::VALUE_SPLIT.count($values);

        foreach ($values as $part_nr => $v) {
            $to_set[$key.$part_nr] = $v;
        }

        if (false === $this->memcached->setMulti($to_set)) {
            $msg = sprintf(
                'Unable to store split values for key "%s": %s.',
                $key,
                $this->memcached->getResultMessage()
            );

            $this->getLogger()->log(LogLevel::NOTICE, $msg);
            throw new \RuntimeException($msg);
        }

        return $value;
    }