Linux System Administration

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Chapter 6: Administering Apache

Benchmarking

Our primary goal was to install and configure our web server correctly and securely.

Beyond this, we want to ensure that it can handle the expected load for our web

sites. The Web has many moving parts, and it’s easy for one to get stuck or fly off

with a faint whistle. To see how our system performs, we’ll use benchmarking tools

to simulate hundreds of fast-typing users (which is much cheaper than actually hir-

ing hundreds of fast-typing users).

Apache can run with different versions, called models. The default

installation under Debian is the prefork model, in which multiple

Apache processes are started to handle requests. This seems to be the

model that works best under Linux.

At least one static HTML file is required for benchmarking. Create a file called /var/

www/bench.html. It should be roughly the size you expect a typical web page on your

site to be. You can impress your friends by generating Latin text at http://www.

lipsum.com to cut and paste into bench.html. The benchmarking program, ab,isin

the apache2-utils package, and it should have been installed with Apache. Let’s make

1,000 separate requests for the same file, with a concurrency (simultaneous requests)

of 5:

# ab -n 1000 -c 5 http://server1.centralsoft.org/bench.html

This is ApacheBench, Version 2.0.41-dev <$Revision$> apache-2.0

Copyright (c) 1996 Adam Twiss, Zeus Technology Ltd, ...