Archery 平台执行DDL error：Threads_connected exceeds its critical threshold

在数据库管理平台Archery上定时任务执行DDL操作，第二天发现报错，报错信息如下：

Error copying rows from `DB`.`TABLE_NAME` to `DB`.`_TABLE_NAME_new`: Threads_connected=1358 exceeds its critical threshold 1300

登录查看Threads_connected信息，Threads_connected 一直处于大于1300个连接：

mysql> show status like '%thread%';
+------------------------------------------+----------+
| Variable_name                            | Value    |
+------------------------------------------+----------+
| Com_show_thread_statistics               | 0        |
| Delayed_insert_threads                   | 0        |
| Innodb_master_thread_active_loops        | 30810790 |
| Innodb_master_thread_idle_loops          | 45       |
| Performance_schema_thread_classes_lost   | 0        |
| Performance_schema_thread_instances_lost | 0        |
| Slow_launch_threads                      | 0        |
| Threadpool_idle_threads                  | 92       |
| Threadpool_threads                       | 99       |
| Threads_cached                           | 0        |
| Threads_connected                        | 1368     |
| Threads_created                          | 2283216  |
| Threads_running                          | 8        |
+------------------------------------------+----------+

查看inception中变量值设置：

[root@hankyoon ~]# mysql -h127.0.0.1 -uroot -P6669

mysql> inception get variables ;
...
...
...
| inception_osc_critical_thread_connected  | 1300                                      |
...
...
...

修改inception_osc_critical_thread_connected值，为1800

mysql> inception set inception_osc_max_thread_connected = 1800;

在Archery平台重新提交DDL SQL即可.