I'm Kevin. I live in Salem, Mass with my wife and little boy and I build software.

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

Rough Results:

No Drupal caching; No opcode caching
AB	Anonymous	5.23 req./sec.
AB	Authenticated	3.20 req./sec.
Siege	Anonymous	7.0 req./sec.
Normal Drupal caching; No opcode caching
AB	Anonymous	121.34 req./sec.
AB	Authenticated	6.40 req./sec.
Siege	Anonymous	218.83 req./sec.
Normal Drupal caching; eaccelerator enabled
AB	Anonymous	338.31 req./sec.
AB	Authenticated	14.49 req./sec.
Siege	Anonymous	543.50 req./sec.

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.