IXIA\'s Chariot - learning curve / features
I've been using LoadRunner heavily for about 6 months and we are considering moving to IXIA's solution for Performance and Load testing. However, our current schedules are short and I have 2 questions: 1) What is the learning curve on Chariot? (for a quick learner)
2) How do the features of Chariot compare to LoadRunner when is comes to testing Web based applications?
Thanks in advance.
Re: IXIA\'s Chariot - learning curve / features
Hey, great question! I know both tools very well and actually wrote the first training class for Chariot (when it was ownder by Ganymede software) back in 1998. The class is fundamentally the same today as it was then. I have also worked for Mercury Interactive in both the sales and professional services organizations and have both held instructor credentials as well as evaluated instructors for the product. In short, I have a good feel for the engineered efficiencies of both tools.
The tool are not replacements for one another. IxChariot does not exercise the application, but instead represents the data flows generated across the network representing the behavior of the application. Press a button in an interface and a presentation layer conversation begins with a backend server host of some type. LoadRunner captures and replaces the client in the conversation, exercising the full application. IxChariot replaces client and server with endpoint processes and reproduces the set of flows associated with the application between a client endpoint and a server endpoint from the session layer of the OSI model (instead of the presentation layer as is most of LoadRunner).
IxChariot's distinct technical feat is that it can time, from the bottom of the session layer, the round trip time in the network generated by the aforementioned client request. While the press of the OK button may result in a SQL Query, an HTML Get, a Telnet session being started, fundamentally these flows are represented in IxChariot as a set of send and Receive patterns.
</font><blockquote><font size="1" face="Verdana, Arial, Helvetica">code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">This is pseudo code
SEND 52 RECV 52
content=<some file> content=<some file>
REV 14576 SEND 14576
content=<some file> content=<some file>
...</pre><hr /></blockquote><font size="2" face="Verdana, Arial, Helvetica">In the end, in the equation network_response+application_response=total_respon se_time, IxChariot can provide a view of the unadultered network response time that LoadRunner and other application testing tools cannot provide.
Here's how I use the two together collaboratively: While LoadRunner is being used to proof the application in an isolated testing network I will use IxChariot to proof out the production network where the application will reside. I can tune the production network while the application is being tuned, so Ideally I have no suprises when I combine the two. This methodology allows me to prevent a huge finger pointing exercise of "your app" versus "your network" when the application has performance problems.
The two products have radically different focuses in what components of the application infrastructure/application architecture they both load and sample against. To test your apps, use LoadRunner (or equivalent). When you need a distinct network sample for a given pattern of flows representing a business transaction, then use Chariot. Most of the scenario construction skills are very transferable between the tools. If you are used to scripting in LoadRunner, then you will find the scripting engine in IxChariot radically different because of the focus of the product. Chariot scripts only support a single transaction name per script and also are single session based. I would like to see a multi-transaction model become available in Chariot. Is the single session thing a deal killer? Probably not, as there are still some application load testing tools on the market that fall into that category.
I do have a whitepaper on sampling methods that I authored several years ago on this very subject of Chariot versus LoadRunner. It has often been distributed by NetIQ and Ixia as part of their sales positioning of the tools. If you want a copy sent to you, then drop me a note.
Replace ineffective offshore contracts, LoadRunnerByTheHour
. Starting @ $19.95/hr USD.
Put us to the test, skilled expertise is less expensive than you might imagine.
Twitter: @LoadRunnerBTH @PerfBytes