请参考https://docs.pingcap.com/zh/tidb/stable/troubleshoot-hot-spot-issues#%E4%BD%BF%E7%94%A8-shard_row_id_bits-%E5%A4%84%E7%90%86%E7%83%AD%E7%82%B9%E8%A1%A8和https://docs.pingcap.com/zh/tidb/stable/troubleshoot-hot-spot-issues#%E4%BD%BF%E7%94%A8-auto_random-%E5%A4%84%E7%90%86%E8%87%AA%E5%A2%9E%E4%B8%BB%E9%94%AE%E7%83%AD%E7%82%B9%E8%A1%A8