Cannot find the Mariadb Storang Engine Innodb configuration file

Hi developers,
I have installed the Frappe & Erpnext version 13, now i am going to make some changes related to mariadb performance configuration but can not find the innodb settings like innodb_buffer_pool_size etc. I have looked into my.cnf , 50-server.cnf but did’t find the innodb settings. can you people please guide me, where i can find those configurations?