Know thy limits! This is especially important when you’re developing a system that expects a high traffic. Moving systems onto the cloud makes it easier to adapt and scale out to match the load but you have to prepare for node failures and instant spikes in the traffic. Also you have to make sure that your system is responsive under long heavy load. Below I recommend 3 tools to test your system against such situations:

01. JMeter

Apache JMeter, is a Java-based open-source desktop application. I submitted a basic introduction to JMeter here. But it has many advanced feature which I’m planning to cover in a post in the near future.

02. Siege

Siege is an HTTP load testing tool. It’s not complex as JMeter but works the job well and it is very simple to use. It supports UNIX variants but not on Windows. It can obtained from here.

03. Chaos Monkey

Originally developed by Netflix and open-sourced later. It is AWS specific tool. What is does is connect to your AWS system and terminate instances randomly. So that you can observe your system in such worst case scenarios. The good thing about it is, it selects its “victims” by looking at a tag you provide. So if you don’t want a single node such as a database server, you can easily exclude it. Source code can be downloaded from here.