show variables like 'innodb_buffer_pool_size';
set global innodb_buffer_pool_size=53687091200;# 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 | 85899345920 |
+-------------------------+-------------+
1 row in set (0.00 sec)
Fri Oct 25 12:34:46 2019> set global innodb_buffer_pool_size=53687091200;
Query OK, 0 rows affected (0.00 sec)
Fri Oct 25 12:35:25 2019> show variables like 'innodb_buffer_pool_size';
+-------------------------+-------------+
| Variable_name | Value |
+-------------------------+-------------+
| innodb_buffer_pool_size | 85899345920 |
+-------------------------+-------------+
1 row in set (0.00 sec)
Fri Oct 25 12:35:28 2019> show variables like 'innodb_buffer_pool_size';
+-------------------------+-------------+
| Variable_name | Value |
+-------------------------+-------------+
| innodb_buffer_pool_size | 85899345920 |
+-------------------------+-------------+
1 row in set (0.00 sec)
Fri Oct 25 12:35:38 2019 > show variables like 'innodb_buffer_pool_size';
+-------------------------+-------------+
| Variable_name | Value |
+-------------------------+-------------+
| innodb_buffer_pool_size | 85899345920 |
+-------------------------+-------------+
1 row in set (0.00 sec)
Fri Oct 25 12:35:55 2019> show variables like 'innodb_buffer_pool_size';
+-------------------------+-------------+
| Variable_name | Value |
+-------------------------+-------------+
| innodb_buffer_pool_size | 52848230400 |
+-------------------------+-------------+
1 row in set (0.00 sec)
Fri Oct 25 12:36:16 2019 >