I work on an e-commerce website and we have important performances difference between our production server and our test server.
Both are VM running on Windows Server 2008 R2 64bits with WampServer 2.5 (Apache 2.4.9 / PHP 5.5.12).
(Note : I know that WampServer is not for production uses, but at this time it's still the best solution for us as we highly depend on Windows environment for our databases and other stuff. We tried to optimize Apache & PHP configuration for production, and we replicated that conf on our test server, so we have the same environment on both machines.)
Everything was running okay from there, until today. We were attempting to improve Apache files compression configuration (disabling it on images, enabling on html files, etc) when we noticed a major difference between the two servers.
On the same page (for test needs : an huge products list with a lot of content and images to display), same request, same user, same browser :
The production server seems to "prepare" the whole document before sending it. During several seconds I've to wait and watch a blank browser, then all shows up instantly. In Chrome Dev Tools, Waiting time is around 7 sec and Receiving time around 50 msec.
The test server seems to do just the opposite : no blank page during seconds, the header is displaying very quickly and the rest of the content comes step by step while I can already browse the page. Waiting time is around 200 msec and Receiving time around 11 sec.
On my own development machine, I can observe both situations when I toggle Apache's configuration for mod_deflate.
So after several attempts, we just disabled the mod_deflate on the production server, and then on the test server. Both have the exact same configuration, and still there is this big difference. I also looked on php.ini files, thinking about cache issues or something like that, but same deal here : both configuration files are matching but the two servers are still working differently.
We spent hours searching answers on the web, but nothing seems to work...
Please, can somebody help us on that ?
