MySQL每隔一小会不操作报错ERROR 2013 (HY000) Lost connection to MySQL server during query问题

连接OA的MySQL库发现每隔一小会不操作就报错如下：

mysql> select now();
+---------------------+
| now()               |
+---------------------+
| 2022-01-11 09:47:41 |
+---------------------+
1 row in set (0.00 sec)

mysql> select now();
ERROR 2013 (HY000): Lost connection to MySQL server during query
mysql> select now();
ERROR 2006 (HY000): MySQL server has gone away
No connection. Trying to reconnect...
Connection id:    453751
Current database: *** NONE ***

+---------------------+
| now()               |
+---------------------+
| 2022-01-11 09:48:27 |
+---------------------+
1 row in set (0.00 sec)

实际上有两个参数如下：

interactive_timeout = 1800  ##交互式会话空闲超时时间(mysql工具、mysqldump等)

wait_timeout = 1800  ##非交互式会话空闲超时时间，mysql api程序,jdbc连接数据库等

查看数据库的这两个参数值（单位：s）：

mysql> show variables where Variable_name in ('interactive_timeout','wait_timeout');
+---------------------+-------+
| Variable_name       | Value |
+---------------------+-------+
| interactive_timeout | 30    |
| wait_timeout        | 30    |
+---------------------+-------+
2 rows in set (0.00 sec)

由于我是使用mysql数据库本身的命令行交互式客户端mysql，因此调整调整interactive_timeout的值即可。

通过调整interactive_timeout=10,30,60后，会话1连接进去不操作，会话2持续观察：

会话2：
mysql> show full processlist;
+--------+------+---------------------+-------+---------+------+-------+-----------------------+
| Id     | User | Host                | db    | Command | Time | State | Info                  |
+--------+------+---------------------+-------+---------+------+-------+-----------------------+
|      2 | root | ::1:53493           | td_oa | Sleep   |    1 |       | NULL                  |
|     41 | root | ::1:53566           | td_oa | Sleep   |   28 |       | NULL                  |
|     45 | root | ::1:53574           | td_oa | Sleep   |   20 |       | NULL                  |
|   1709 | root | ::1:56311           | td_oa | Sleep   |   68 |       | NULL                  |
| 454546 | root | 192.168.1.188:54046 | NULL  | Sleep   |    7 |       | NULL                  |
| 454553 | root | 192.168.1.188:54048 | NULL  | Query   |    0 | init  | show full processlist |
+--------+------+---------------------+-------+---------+------+-------+-----------------------+
6 rows in set (0.00 sec)