nginx request slowdown.

nginx.conf

http {
# ...
  server {
  
      listen       8081;
      server_name  localhost;
  
      location / {
          proxy_pass       http://localhost:8000/;
          proxy_buffering on;
          # if ($http_x_requested_with = XMLHttpRequest) {
              limit_rate 5k;
          # }
      }
      
      location ^~ /static/ {
          # limit_rate_after 1m;
          limit_rate 200k;
          proxy_pass       http://localhost:8000/static/;
          proxy_buffering on;
      }
  }
# ...
}