Which is the best performance testing tool when i dont know the client application behaviour. As i am going to have number of web based clients

Question

My organization is looking to perform a performance testing externally. The performance testing is going to be only for web based applications. Can you guide me which tool is best to choose as performance testing tool. Right now there is no idea about the client web application behaviour. Beacuse there could be number of clients. What is the minimum configuration i should look for a hardware?

Can i get 100 percent accurate results using an open source tool in market? I am really struck with these intial doubts. I am new to performance testing. Your answers are highly helpful

Answer 1

I am new to performance testing.

Then you should have a mentor that you will be working with for a period of time. The tool selected represents about 5-15% of the solution set for conducting a performance test.

Write down your requirements for reporting, analysis, the skills of your team, the applications and hosts you need to monitor, the environment your tool needs to run in. Use these requirements as a lens through which to view your options.

As to the accuracy, I would invite you to take the following into consideration as part of your testing efforts: Evaluate the tools technically. Look at the load from one live user on your box in terms of IP connections, HTTP sessions, etc..., then using the same tools look at how your tool generates its load. You will find some differences. Some tools, quite popular, will use a smaller number of sessions and piggyback requests from multiple users across an open connection. This will reduce the number of connections versus a natural population and make your job of finding bottlenecks in the session side of the house very difficult. I will not identify the tool/tools so inclined, that will be for your research. You will want to perform this evaluation for one, five and ten users to see how your load is shaped and the structural differences between the tools.

The big commercial vendors all have smaller virtual user versions of their tools at no charge. You can use these versions to evaluate against your requirements and your technical evaluation of a match to true user behavior

Answer 2

If you're looking for a free and open-source performance testing tool I would recommend going for one of the following:

• Grinder
• Gatling
• Tsung
• Apache JMeter

They're more or less equal in their load testing capabilities when it comes to web applications, however they differ, i.e.

• You need to know Python if you use Grinder
• Gatling offers easy-readable DSL for test scenarios development and customization is done with Scala
• Tsung can generate more load given the same hardware but it doesn't provide any GUI and works on Linux and Unix only
• JMeter development is done through a Tree of Components in GUI, and there is a DSL if you want code and no GUI. Customization of scripts can be done through any language providing JSR223 bridge (Groovy, Scala, Java, JRuby...).

So if you're new to performance testing domain I would recommend Apache JMeter. However you're welcome to check out:

• Open Source Load Testing Tools: Which One Should You Use? where you can get familiar with main features, see what sample load reports look like and look at comparison matrix.

• Comparison of 3 Major tools that shows a side by side comparison of tools

Answer 3

jMeter is the good answer here, as it is free, you can easily record some scenarios if you never worked with tools like that and if thinking about load tests for 1k threads (users) or so it's still quite easy to do, you just need to go with remote testing (link here).

And something about tips and tricks, that is really helpful when you go through some tutorials, write some tests and then you will see that it is not exactly as you wanted.