MySQL常见问题入坑出坑

# 1.查看MySQL8.x默认最大链接数。
mysql> show variables like "max_connect%";
+--------------------+-------+
| Variable_name      | Value |
+--------------------+-------+
| max_connect_errors | 100   |
| max_connections    | 151   |
+--------------------+-------+
2 rows in set (0.04 sec)

# 2.设置临时生效的全局命令设置。
set global max_connections=2000;
set global max_connect_errors=500;

# 查看最大睡眠时间
mysql> show global variables like 'wait_timeout';

# 设置300自动杀死线程
mysql> set global wait_timeout=300;