def hiveconfs(self):
        """
        Returns a dict of key=value settings to be passed along
        to the hive command line via --hiveconf. By default, sets
        mapred.job.name to task_id and if not None, sets:

        * mapred.reduce.tasks (n_reduce_tasks)
        * mapred.fairscheduler.pool (pool) or mapred.job.queue.name (pool)
        * hive.exec.reducers.bytes.per.reducer (bytes_per_reducer)
        * hive.exec.reducers.max (reducers_max)
        """
        jcs = {}
        jcs['mapred.job.name'] = "'" + self.task_id + "'"
        if self.n_reduce_tasks is not None:
            jcs['mapred.reduce.tasks'] = self.n_reduce_tasks
        if self.pool is not None:
            # Supporting two schedulers: fair (default) and capacity using the same option
            scheduler_type = luigi.configuration.get_config().get('hadoop', 'scheduler', 'fair')
            if scheduler_type == 'fair':
                jcs['mapred.fairscheduler.pool'] = self.pool
            elif scheduler_type == 'capacity':
                jcs['mapred.job.queue.name'] = self.pool
        if self.bytes_per_reducer is not None:
            jcs['hive.exec.reducers.bytes.per.reducer'] = self.bytes_per_reducer
        if self.reducers_max is not None:
            jcs['hive.exec.reducers.max'] = self.reducers_max
        return jcs