Very interesting test results from some regression testing I did today for a client. I was using Siege and Apache AB for anonymous user testing, and attempting to simulate authenticated users by specifying cookie data with AB. The tests were done remotely from an EC2 instance.
Here were the basic commands:
ab -t 300 -kc 50 http://example.com/ ab -t 300 -kc 50 -CSESS[...]=[...] http://example.com/ siege -c 50 -t 300s -f url_list.txt
|No Drupal caching; No opcode caching|
|Normal Drupal caching; No opcode caching|
|Normal Drupal caching; eaccelerator enabled|
I ran each test a few times and selected the median value. So, these aren't 100% conclusive, but there is definitely a trend here. The interesting thing is the huge difference between anonymous and authenticated users.