How to rigorously test a site?

Question

How does one rigorously test a site for both security and speed?

What are the ways and tools for that?

Can we mimic hundreds of virtual users visiting the site to see its load handling?

Answer 1

I suggest you read this post, its very useful I check my dynamic web sites each time I build one.

https://stackoverflow.com/questions/72394/what-should-a-developer-know-before-building-a-public-web-site#answer-305381

Edit :

http://jmeter.apache.org/

Apache JMeter is open source software, a 100% pure Java desktop application designed to load test functional behavior and measure performance. It was originally designed for testing Web Applications but has since expanded to other test functions.