#####################################

在线更改是有风险的：

 

 ################

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 >

 

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