mysql5.7在线更改innodb_buffer_pool_size

show variables like 'innodb_buffer_pool_size';

set global innodb_buffer_pool_size=;
# 在线更改该值时，不会立即生效，大概需要30s左右的时间才会完全生效。
########################################################
> show variables like 'innodb_buffer_pool_size';
+-------------------------+-------------+
| Variable_name           | Value       |
+-------------------------+-------------+
| innodb_buffer_pool_size |  |
+-------------------------+-------------+
 row in set (0.00 sec)

Fri Oct  :: > set global innodb_buffer_pool_size=;
Query OK,  rows affected (0.00 sec)

Fri Oct  :: > show variables like 'innodb_buffer_pool_size';
+-------------------------+-------------+
| Variable_name           | Value       |
+-------------------------+-------------+
| innodb_buffer_pool_size |  |
+-------------------------+-------------+
 row in set (0.00 sec)

Fri Oct  :: > show variables like 'innodb_buffer_pool_size';
+-------------------------+-------------+
| Variable_name           | Value       |
+-------------------------+-------------+
| innodb_buffer_pool_size |  |
+-------------------------+-------------+
 row in set (0.00 sec)

Fri Oct  ::  > show variables like 'innodb_buffer_pool_size';
+-------------------------+-------------+
| Variable_name           | Value       |
+-------------------------+-------------+
| innodb_buffer_pool_size |  |
+-------------------------+-------------+
 row in set (0.00 sec)

Fri Oct  :: > show variables like 'innodb_buffer_pool_size';
+-------------------------+-------------+
| Variable_name           | Value       |
+-------------------------+-------------+
| innodb_buffer_pool_size |  |
+-------------------------+-------------+
 row in set (0.00 sec)

Fri Oct  ::  >