We are using nginx as reverse proxy. There are 4 servers (1x nginx, 2x uWSGI, 1x DB + Memcached). One user told me some time ago, that he has for 3 months problems with loading speed of website. Every request takes 5-10 secs, when for me it takes less than second. What can cause problem? When I did test, and give him access to other IP but NATed to same local address:port, he told me that it's faster, but not yet fast enough.
Our structure - Network -> NAT external IP to internal -> nginx.
I would approach this problem in a three step fashion:
1) Use tcping from your computer and his computer to see the latency differences. tcping.exe is a small console application that operates similarly to 'ping', however it works over a tcp port.
2) Use the Firefox plug-in FireBug and/or Yahoo's YSlow. These will tell you which part of the web page is loading slowly.
3) Check that slow DNS resolution is not slowing him down.
ipconfig -flushdns if you havent tried it yet, then also clear his cashe in the browser. maybe clear your cashe in your proxy device, our bluecoat devices will cashe sites behind the reverse proxy. i just clear the cashe and things run smoother.
