title: Proxy choices: mod_proxy_balancer, nginx + proxy balancer, haproxy?
body: <p>We're running a Rails site at <a href="http://hansard.millbanksystems.com" rel="nofollow noreferrer">http://hansard.millbanksystems.com</a>, on a dedicated Accelerator. We currently have Apache setup with mod-proxy-balancer, proxying to four mongrels running the application.</p>
  
  <p>Some requests are rather slow and in order to prevent the situation where other requests get queued up behind them, we're considering options for proxying that will direct requests to an idle mongrel if there is one.</p>
  
  <p>Options appear to include:</p>
  
  <ul>
  <li><p>recompiling mod_proxy_balancer for Apache as described at <a href="http://labs.reevoo.com/2008/7/30/fixing-uneven-load-balancing-between-apache-and-mongrel-for-ruby-on-rails-applications" rel="nofollow noreferrer">http://labs.reevoo.com/</a></p></li>
  <li><p>compiling nginx with the fair proxy balancer for Solaris</p></li>
  <li><p>compiling haproxy for Open Solaris (although this may not work well with SMF)</p></li>
  </ul>
  
  <p>Are these reasonable options? Have we missed anything obvious? We'd be very grateful for your advice.</p>