First, benchmarking a web server is not an easy thing. To benchmark a
web server the time it will take to give a page is not important: you don't
care if a user can have his page in 0.1 ms or in 0.05 ms as nobody can have
such delays on the Internet.
What is important is the average time it will take when you have
a maximum number of users on your site simultaneously. Another
important thing is how much more time it will take when there
are 2 times more users: a server that take 2 times more for 2
times more users is better than another that take 4 times more
for the same amount of users. If you run more than a web server
on your computer, you will also want to look at the load average
and CPU time of your system. Here is a typical output of the
command uptime:
22:39:49 up 2:22, 5 users, load average: 0.01, 0.01, 0.00
And an extract from the top(1) man page:
"
The load averages are the average number of process ready to run during
the last 1, 5 and 15 minutes
"
So the lower your load average is, the better for the other
programs on your machine.
Now comes the next problem: how can you stress your web server with a maximum
number of connections when your client (the machine making the request) will
usually not be able to cope with the server and with the number of users you
have.
To do this, increase the number of sockets you can have on your
system. Under some systems it is 1024, which is too low, see
Section 5.3 for more information. The
next thing to do is to have a good client program written with
threads and non-blocking sockets. If you use a multi-fork
program on a single client, it will never cope with any web
server. It is also good to have several clients stressing the
server together.
Last, if you want to compare two web servers, be sure that they are on the
same hardware, OS, and network. The same holds for the client(s).
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