https://confluence.atlassian.com/adminjiraserver0817/connecting-jira-applications-to-mysql-5-7-1071815640.html
https://confluence.atlassian.com/adminjiraserver0817/connecting-jira-applications-to-a-database-1071815634.html#ConnectingJiraapplicationstoadatabase-UpgradingJiraormigratingJiratoanotherserver?

[mysqld]

Remove leading # and set to the amount of RAM for the most important data

cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%.

innodb_buffer_pool_size = 128M

Remove leading # to turn on a very important data integrity option: logging

changes to the binary log between backups.

log_bin

Remove leading # to set options mainly useful for reporting servers.

The server defaults are faster for transactions and fast SELECTs.

Adjust sizes as needed, experiment to find the optimal values.

join_buffer_size = 128M

sort_buffer_size = 2M

read_rnd_buffer_size = 2M

datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock

Disabling symbolic-links is recommended to prevent assorted security risks

symbolic-links=0

log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

below are customed

validate_password=off
default-storage-engine=INNODB
character_set_server=utf8mb4
innodb_default_row_format=DYNAMIC
innodb_large_prefix=ON
innodb_log_file_size=2G
innodb_file_format=Barracuda
~