Response from proxy server buffered in memory? (no replies)

I configured nginx as reverse proxy to an application server java disabling the proxy buffering:

proxy_buffering off;
proxy_request_buffering off;

I noticed that when a client makes a request to the java server (e.g. download a file), nginx buffered the response in memory (around 3Mb).
I would like to configure nginx so as not buffered the response (or at least minimize this buffer) it is possible?


Thanks,
Danilo Limatola Esterno