i am performing some httperf tests against apache and nginx. something i noticed that piqued my interest were the consistency of response times (0.4 ms each run regardless of number of request, much lower than apache in all cases) and network I/O (consistently higher than apache regardless of number of request). it also uses less cpu than apache and doesn't nearly drive up the load.

are these normal results? is there a mechanism in nginx that keeps the response times low and consistent? also, is it normal that it uses more network I/O? if so, what is the cause? to me it would seem like that it uses more bandwidth to respond to the same number of requests which seems inefficient.

please correct me if i am wrong. i am just trying to understand the core differences in how nginx works in comparison to apache and why i would see these performance differences.

thanks for the help.