Apache Benchmark

[fafabone]

I'm using AB (Apache Benchmark) for testing concurrent connections on Apache Server on a Linux Server.
I'm using connectd to store server parameters as cpu delays, memory consumption and load.
All these parameters are really under the critical values: memory is less than 2GB on 24GB total, cpus are busy less than 30% of time and load is less than 10. What is strange is the time that requests take to be delivered.
With 4096 concurent connections and 50'000 request this is the output (percentage of the request served in the time of the second column). Max load:6
Percentage served Time in ms
0 174990
1 461443
2 662093
3 1098610
10 3589700
15 4589651
25 10583467
30 16469471
40 63096433
50 63102546
60 63103907
70 63107560
80 63126287
90 63156905
99 63905927
Can you suggest why the connections take so long time to be delivered?
I have not insert directives on httpd.conf of apache server. Do I need to insert max_connection or others?

[Nobbie]

Do you have a real problem or are you simply wasting your time by useless benchmarks?

What is your actual problem with Xampp? Xampp is not designed to work in online environment - what is the idea of running an online benchmark on a development environment?