PHP-FPM NGiNC Memory

Hello.
I have site on nginx1.10.3 wich reads from db a lot of records, makes an ordering with php7.3-fpm and then served to the public.
Records are quite few and I would like to give it more memory so as to perform better.
I dont know where this extre memory should be given. To nginx or to php7.3-fpm?

any help is appreciated.