Load Runner Interview Questions

1. What type of LR license are you using? Term Licensing for 1year with 500 Vusers 2. Do you have license for protocols? Not sure 3. What is the process that you follow starting from PT requirements? Identify the Scenarios → Plan the Load Test → Design The load Test (Scripting the Vuser) → Create the Scenario (Controller) → Design Scenario → Execute Scenario → Monitor the Scenario → Generate the Report → Analyse the Report No

4. Is license required for VuGen?

5. Is it possible to record with Ajax (click & script) & web (click & script) in multiple protocol scenarios? No 6. Which protocol you would recommend for testing performance for Dotnet applications implemented with Ajax and why? Ajax (click & script) OR web (click & script) OR MS.Net protocols. 7. Imagine you are running a load test and after some time controller generated the error. What will be your reaction and what you will observe? I will look into the Log message window in controller and identify why the error is thrown & if needed I will make enhancement to my Vuser script in Vugen and then run the script in debug mode to make that the Vuser script does not fail and will refresh the script in controller and the start the scenario back. 8. What is the process followed while scripting in Vugen? Identify the protocol (protocol Advisor) → create a new Vuser script by selecting the supporting protocol → Record the actions with appropriate recording options → Generate Script → Run the script → Identify the dynamic values and correlate all the dynamic values and run the script 9. Suppose in the middle of Performance testing phase, you get a new requirement and starting from development to functional testing have to implement the new requirement. what type of changes you will incorporate in PT and how you will plan to test the req. I would take the requirements change impact report document and discuss with the business analyst and devlopers to identify the impact of the req change or new req on the application and will identify the areas that would be impacted. And will add this to my perf test plan and then carry out my performance testing activites once I receive the regression report after the req is implemented in the application. 10. Explain correlation process. Correlation is a technique to handle the dynamic values generated by the server like session id's or serialization id's by replacing them with the current values generated during the run-time. 11. What type of monitors have you setup? I worked with various monitors at App server level and monitors of windows resouces of the servers and few monitors at db level. App server monitors – JVM size, Connection ppol, GC, Heap size, free memory etc.; Windows resources – CPU utilisation, processing time, Process, Virtual memory, page faults etc.: Db monitors – Top time consuming sql's, poor indexes, dead locks, etc... 12. What type of servers have you worked on? Worked on App servers like Weblogic, Jboss, MS-IIS 6.0 and db servers like DB2 and sql server.

13. Suppose a client had not provided with performance objectives. In that case how you will provide? 14. For a typical PT project, what type of documents do you expect for a client ? Documents related to the High level and low level architecture of the application. Design documents and documents that descibe the usage of thrid party components and external communication components and documents that describe the communication architecture of the application and use cases and test cases of the business critical scenarios and documents related to the system service levels and documents of h/w , s/w re's etc...... 15. What types of bottlenecks have to identified in your latest project ? Poor GC, constant high usage of VM, connection pools, poor indexing and complex sql queries etc. 16. What is the response time for the application that you have tested in your recent project? It varies from business scenario to business scenario, the response time for critical business scenario is 3 sec's. 17. What are the recommendations that you have provided for the client? Poor GC, constant high usage of VM, connection pools, poor indexing and complex sql queries etc. 18. What are the challenges you have faced till now in PT? To simulate the load on EJB applications that uses RMI protocols over IIOP 19. What is the difference between Load testing and endurance testing. Load Testing – Test objective is to find the application behaviour is terms of response time under anticipated load. Endurance – Test Objective is to simulate load on an application upto a period of time to monitor the application performance for longer periods. 20. How many controller and LG machines you have? 1 controller and 4 load generators. 21. Do you test at offshore or onsite? Offshore 22. What type of settings have you done for Web (click & script) protocol? Change the Event configuration Level, Select appropriate mode(GUI/URL/HTML) etc.. 23. Suppose while recording in Web (HTTP) protocol, you could not correlate dynamic values. What will do? Will look into the Response Log of the function while recorded. 24. What type of reports have you generated? 25. What differences you observed between LR 8.0 & LR 9.5 Protocol Advisor, Parameter Simulator, Business process report, User defined template. 26. Suppose you are running a scenario in a controller and in the middle you want to ramp up 20 Vusers. Is it possible? Yes we can ramp up the Vusers. 27. What are the differences between URL mode and HTML mode and in what context you choose one over another while selecting protocol for recording? The HTML-based script level generates a separate step for each HTML user action. The steps are also intuitive, but they do not reflect true emulation of the JavaScript code.

The URL-based script mode option instructs VuGen to record all browser requests and resources from the server that were sent due to the user's actions. It automatically records every HTTP resource as URL steps (web_url statements). For normal browser recordings, it is not recommended to use the URL-based mode since is more prone to correlation related issues. If, however, you are recording pages such as applets and non-browser applications, this mode is ideal. 28. How will you define the complexity of a performance scenario? Usually by looking at the number of transactions & the no of correlations 29. Where do you observe the AppServer & DB logs? 30. What errors you observed in Server & DB logs? 31. What are the contents of an analysis report? 32.What is correlation? Correlation is a technique to handle the dynamic values generated by the server like session id's or serialization id's by replacing them with the current values generated during the run-time.

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33.What are the atleast 5 attributes defined in a Web_reg_save_param() like ORD=ALL ? LB=; RB=; Search= ; Convert= ; ORD= ; NOTFOUND= ; SaveLen= ; RelFrameID= ; SaveOffset= ;

34.What is Sprintf() ? Writes formatted output to a string 35.What is the difference between Recording Log, Generation Log, Replay Log ? Recording Log: A Network Analyzer would analyze the communication happing at network level and logs the events. Generation Log: Logs the events happening while generating the Vuser script after recording. Replay Log: Records the events of happening when executed a function in the script. Will be logged at each line level of the script. 36.As you employ the settings of Logging(Standard, Extended) for a script in RunTime settings, How do you do this using code lr_set_debug_message(LR_MSG_CLASS_EXTENDED_LOG, LR_SWITCH_ON) lr_set_debug_message(LR_MSG_CLASS_EXTENDED_LOG,LR_SWITCH_OFF) 37.How to convert a variable to a LR Parameter ? lr_save_string() ; lr_param_sprintf() Example: int index = 56; char * suffix = "txt"; lr_param_sprintf ("LOG_NAME_PARAM", "log_%d.%s", index, suffix,100); lr_output_message("The new file name is %s",lr_eval_string("{LOG_NAME_PARAM}"));

Output: Action.c(9): The new file name is log_56.txt 38.What is the definition of AJAX ? Asynchronous JavaScript and XML 39.What is the difference between a plain HTTP protocol & AJAX protocol ? 40.What are 2 functions to stop a script (One LR function and C function) ? lr_abort() ; lr_exit() ; 41.How do you upload a file using a LR script? 42.What is a rendezvous point & if you insert a rendezvous point in your script, What settings do you employ in your scenario ? Will Define the Rendezvous Policy in Scenario settings. 43.What is IP Spoofing? Why do we use it ? When testing using Web and WinSocket protocols, by default Vusers on each host machine use the host's (agent's) IP address. Since a particular server keeps serving a specific IP address, load tests would reflect network router caching and other optimizations rather than the real-life situation where different users arrive to the server with different IP addresses. This is especially needed when the hardware configuration under test balances load across a "farm" of several (web or database) servers. "IP spoofing" enables each host machine to "spoof" the server into thinking it is using many different IP addresses. 44.I hav a set of Vusers in my scenario scheduled for 10 hours and I want the controller to display the status of each Vuser dynamically ..i.e I want to know what each Vuser is doing and what transaction or action is doing ? For this what settings do you employ in your scenario ? 45.Did you ever come across an instance where you need to simulate Java script in your AJAX protocol? 46.What functions would be generated when selected AJAX protocol ? Web_Submit_Data(); 47.Do you use regular expression in correlating your script ?