How to fix problem with Nginx and buffer?

Question

PHP

I have a problem with the fact that the site should give static large files (zip, rar). But the problem is that the error "an upstream response is buffered to a temporary file" appears in the logs. I wrote "fastcgi_buffering off;" in the config, but because of this, the site starts to load for a long time, a 502 error appears, and in the logs
" connect() to unix:/var/www/php-fpm/socket.sock failed (11: Resource temporarily unavailable)".
Server 12gb, 2 cores. php
config pm.max_children = 400
pm.start_servers = 8
pm.min_spare_servers = 8
pm.max_spare_servers = 16

Answer 1

Do not give large files through fastcgi.
https://www.nginx.com/resources/wiki/start/topics/...
https://www.opennet.ru/base/net/nginx_x_accel_redi...