apache w/modphp has the best latency in comparison to any fastcgi setup. When it comes to high concurrency latency and time to finish is your biggest issue. S

apache w/modphp has the best latency in comparison to any fastcgi setup. When it comes to high concurrency latency and time to finish is your biggest issue. Slow clients are another killer (slow clients are users who have a slow connection and take an order of magnitude longer or more do download the page data as compared to generation). If you application is fast (less than 20ms) page generation your best bet is the following setup... nginx or varnish reverse proxy front end. (depending on your load you can turn keepalives on here) This front end isolates your www/php/db from slow clients making sure that your request gets processed fast, resources are released, and then a light process of your proxy handles the delivery of the data. On the back end use apache/mod_php with a limit of only 50-100 clients.