Which php.ini file is loaded for octane with Roadrunner in Laravel?

I have installed Octane server with Roadrunner and I have a request which have more than 1000 lines of request payload which was even a problem in php-fpm. I could adjust the value in the php.ini file for the key max_input_vars and the problem was solved. Now since I am using the Octance server, I am not sure how to customize the php.ini settings.