Building a High‑Performance Web Cluster: Load‑Generating Tools and Tsung Configuration Guide

This article is the first part of a series on building a web cluster capable of handling three million requests per second, focusing on load‑generating tools and practical experience.

It explains the importance of load generators for testing server performance under high load and discusses Linux socket limits, recommending the use of multiple machines to achieve sufficient load.

Various tools are evaluated: Apache Bench (ab) is simple but limited to about 900 req/s; httperf can reach around 1 000 req/s with detailed statistics; Apache JMeter, though more complex, can generate up to 30 000 req/s with plugins; Tsung, a distributed, multi‑protocol tool, can produce 40 000 req/s or more and is configured via XML.

The article provides step‑by‑step installation commands for Tsung on CentOS:

yum -y install erlang perl perl-RRD-Simple.noarch perl-Log-Log4perl-RRDs.noarch gnuplot perl-Template-Toolkit firefox

wget http://tsung.erlang-projects.org/dist/tsung-1.4.2.tar.gz

tar zxfv tsung-1.4.2.tar.gz

cd tsung-1.4.2 && ./configure && make && make install

It then shows the essential XML configuration (clients, servers, load phases, sessions, and request loops) and explains each element in detail.

Command‑line snippets for starting Tsung and generating reports are also included:

tsung start

alias treport="/usr/lib/tsung/bin/tsung_stats.pl; firefox report.html"

Finally, it outlines a roadmap for using Tsung to benchmark a single HTTP server, tune TCP sockets, build an LVS cluster, and perform stress testing.