New features introduced in 8.0

mysql> set persist innodb_buffer_pool_size=2048*1024*1024;
Query OK, 0 rows affected (0.01 sec)

MysqL> show variables like 'innodb_buffer_pool_size';
+-------------------------+------------+
| Variable_name           | Value      |
+-------------------------+------------+
| innodb_buffer_pool_size | 2147483648 |
+-------------------------+------------+
1 row in set (0.00 sec)

MysqL> set persist innodb_buffer_pool_size=4096*1024*1024;
Query OK, 0 rows affected (0.01 sec)

MysqL> show variables like 'innodb_buffer_pool_size';
+-------------------------+------------+
| Variable_name           | Value      |
+-------------------------+------------+
| innodb_buffer_pool_size | 4294967296 |
+-------------------------+------------+
1 row in set (0.00 sec)

MysqL> 

[root@roidb3 data]# pwd
/zxdata/my3311/data
[root@roidb3 data]# ls -l MysqLd-auto.cnf 
-rw-r-----. 1 MysqL MysqL 186 Dec 24 08:59 MysqLd-auto.cnf
[root@roidb3 data]# more MysqLd-auto.cnf 
{ "Version" : 1 , "MysqL_server" : { "innodb_buffer_pool_size" : { "Value" : "4294967296" , "Metadata" : { "Timestamp" : 
1577149148131600 , "User" : "root" , "Host" : "localhost" } } } }
[root@roidb3 data]# 

持久化参数直接写入到MysqLd-auto.cnf文件中。具体内容看官方文档。