[httperf] httperf doesn´t generate desired request rate

Florian Berger florib@arcor.de
Wed, 03 Dec 2003 15:12:50 +0100


Hi to all,

I encounter a problem with httperf: It does not generate the request
rate I want it to do.

I´m testing a site involving CGI and generate (just for the example) 50
requests at a increasing rate. No timeouts are involved.

With no rate, httperf reports to issue 2.7 req/s. I take this as a
measure of what the webserver can handle easily.

The second test runs with --rate=2. According to the value above, this
should be no problem. httperf reports 2.0 req/s and nearly the same
connection time values, as expected.

Now I increase the load very slightly: --rate=3. But now httperf still
reports it run at a request rate of 2.7 req/s.

Last test: --rate=5. Still got 2.7 req/s.

You can find the test reports at
http://home.arcor.de/florib/rate-tests.txt

As I understand it, httperf should _send_out_ requests at the given
rate, even if the server cannot _handle_ them. But it obviously does
not, preventing me to run useful tests with som dozens requests a
second and some thousand requests in total. Any ideas why?


My setup:

Server: Celeron 300 MHz, 98 MB RAM, Linux 2.2.16, Apache 1.3, mod_perl,
Realtek 8029AS 10 MBit NIC

Client: Pentium 166 MHz, 64 MB RAM, Linux 2.2.16, httperf 0.8, Realtek
8029AS 10 MBit NIC

Connected via 10baseT, Twisted Pair crossover cable


Any help would be greatly appreciated.

Regards,

     Florian Berger, Leipzig, Germany