MySQL max_connections of Ubuntu 20.04 LTS

I updated the file /etc/mysql/mysql.conf.d/mysqld.cnf to include line max_connections = 65535. I restarted the MySQL server with sudo service mysql restart. Then in the MySQL client I entered the command SHOW VARIABLES LIKE 'max_connections'; and got the following output:

+-----------------+-------+ | Variable_name | Value | +-----------------+-------+ | max_connections | 9190 | +-----------------+-------+ 1 row in set (0.00 sec) 

I tried this on my desktop and on my dedicated server both running Ubuntu 20.04 LTS. I got the exact same results on both boxes.

What's going on? Why isn't the new max_connections value 65535?

1 Answer

To manage a connection , you need a file descriptor .

The max-connections will be constraint by the max open files .

So check the value of open_files_limit

show global variables like '%open_files_limit%' ; 

To change the value of open_files_limit to 20000 by example you must

1) run the command systemctl edit mysql and this

[Service] LimitNOFILE=20000 

2) systemctl stop mysql

3) systemctl start mysql