tsung is a distributed load testing tool. It is protocol-independent and can
currently be used to stress and benchmark HTTP, Jabber/XMPP, PostgreSQL,
MySQL and LDAP servers.
It simulates user behavior using an XML description file, reports many
measurements in real time (statistics can be customized with transactions,
and graphics generated using GnuPlot).
For HTTP, it supports 1.0 and 1.1, has a proxy mode to record sessions,
supports GET and POST methods, Cookies, and Basic WWW-authentication.
It also has support for SSL.