protected function execute() {
        $this->log('creating the stash storage', backup::LOG_DEBUG);
        $this->create_stash_storage();

        $this->log('parsing moodle.xml starts', backup::LOG_DEBUG);
        $this->xmlparser->process();
        $this->log('parsing moodle.xml done', backup::LOG_DEBUG);

        $this->log('dropping the stash storage', backup::LOG_DEBUG);
        $this->drop_stash_storage();
    }