Performance tuning

[Gabri Mate]

Dear List,

I'm quite newbie concerning nginx so please forgive me for my really
basic questions.

I'd like to use nginx as a caching reverse proxy. After reading the docs
i'm not quite sure about the proxy_buffer_size, proxy_buffers options.

Right now my settings are:

    proxy_max_temp_file_size 256k;
    proxy_temp_file_write_size 64k;
    proxy_buffering     on;
    proxy_buffer_size 4k;
    proxy_buffers 32 32k;

proxy_max_temp_file_size is low because i have to use tmpfs under it
cause the disks are really slow and i have just 512MB on the servers
now, but more memory is on the way.

The proxy servers around 10k states/s.

Please could someone give me a short explanation about these options? I
don't have any performance problems, but with these settings half of my
memory is unused. Could they be utilized with tuned settings?

Best regards,
-- 
Gabri Mate