Common Problem and solution to Software Development Process

Common problems in the software development process :

• Poor requirements - if requirements are unclear, incomplete, too general, or not testable, there will be problems.
• Unrealistic schedule - if too much work is crammed in too little time, problems are inevitable. 
• Inadequate testing - no one will know whether or not the program is any good until the customer complains or systems crash.
• Futurities - requests to pile on new features after development is underway; extremely common.
• Miscommunication - if developers don't know what's needed or customer’s have erroneous expectations, problems are guaranteed.

Common solutions to software development problems :

• Solid requirements - clear, complete, detailed, cohesive, attainable, testable requirements that are agreed to by all players. Use prototypes to help nail down requirements. 
• Realistic schedules - allow adequate time for planning, design, testing, bug fixing, re-testing, changes, and documentation; personnel should be able to complete the project without burning out. 
• Adequate testing - start testing early on, re-test after fixes or changes, plan for adequate time for testing and bug-fixing. 
• Stick to initial requirements as much as possible - be prepared to defend against changes and additions once development has begun, and be prepared to explain consequences. If changes are necessary, they should be adequately reflected in related schedule changes. If possible, use rapid prototyping during the design phase so that customers can see what to expect. This will provide them a higher comfort level with their requirements decisions and minimize changes later on. 
• Communication - require walkthroughs and inspections when appropriate; make extensive use of group communication tools - e-mail, groupware, networked bug-tracking tools and change management tools, intranet capabilities, etc.; insure that documentation is available and up-to-date - preferably electronic, not paper; promote teamwork and cooperation; use protoypes early on so that customers' expectations are clarified.

Type of Testing Should Be Considered

• Black box testing - not based on any knowledge of internal design or code. Tests are based on requirements and functionality.
• White box testing - based on knowledge of the internal logic of an application's code. Tests are based on coverage of code statements, branches, paths, conditions.
• unit testing - the most 'micro' scale of testing; to test particular functions or code modules. Typically done by the programmer and not by testers, as it requires detailed knowledge of the internal program design and code. Not always easily done unless the application has a well-designed architecture with tight code; may require developing test driver modules or test harnesses.
• incremental integration testing - continuous testing of an application as new functionality is added; requires that various aspects of an application's functionality be independent enough to work separately before all parts of the program are completed, or that test drivers be developed as needed; done by programmers or by testers.
• integration testing - testing of combined parts of an application to determine if they function together correctly. The 'parts' can be code modules, individual applications, client and server applications on a network, etc. This type of testing is especially relevant to client/server and distributed systems.
• functional testing - black-box type testing geared to functional requirements of an application; this type of testing should be done by testers. This doesn't mean that the programmers shouldn't check that their code works before releasing it (which of course applies to any stage of testing.)
• system testing - black-box type testing that is based on overall requirements specifications; covers all combined parts of a system.
• end-to-end testing - similar to system testing; the 'macro' end of the test scale; involves testing of a complete application environment in a situation that mimics real-world use, such as interacting with a database, using network communications, or interacting with other hardware, applications, or systems if appropriate.
• sanity testing or smoke testing - typically an initial testing effort to determine if a new software version is performing well enough to accept it for a major testing effort. For example, if the new software is crashing systems every 5 minutes, bogging down systems to a crawl, or corrupting databases, the software may not be in a 'sane' enough condition to warrant further testing in its current state.
• regression testing - re-testing after fixes or modifications of the software or its environment. It can be difficult to determine how much re-testing is needed, especially near the end of the development cycle. Automated testing tools can be especially useful for this type of testing.
• acceptance testing - final testing based on specifications of the end-user or customer, or based on use by end-users/customers over some limited period of time.
• load testing - testing an application under heavy loads, such as testing of a web site under a range of loads to determine at what point the system's response time degrades or fails.
• stress testing - term often used interchangeably with 'load' and 'performance' testing. Also used to describe such tests as system functional testing while under unusually heavy loads, heavy repetition of certain actions or inputs, input of large numerical values, large complex queries to a database system, etc.
• performance testing - term often used interchangeably with 'stress' and 'load' testing. Ideally 'performance' testing (and any other 'type' of testing) is defined in requirements documentation or QA or Test Plans.
• usability testing - testing for 'user-friendliness'. Clearly this is subjective, and will depend on the targeted end-user or customer. User interviews, surveys, video recording of user sessions, and other techniques can be used. Programmers and testers are usually not appropriate as usability testers.
• install/uninstall testing - testing of full, partial, or upgrade install/uninstall processes.
• recovery testing - testing how well a system recovers from crashes, hardware failures, or other catastrophic problems.
• security testing - testing how well the system protects against unauthorized internal or external access, willful damage, etc; may require sophisticated testing techniques.
• compatability testing - testing how well software performs in a particular hardware/software/operating system/network/etc. environment.
• exploratory testing - often taken to mean a creative, informal software test that is not based on formal test plans or test cases; testers may be learning the software as they test it.
• ad-hoc testing - similar to exploratory testing, but often taken to mean that the testers have significant understanding of the software before testing it.
• user acceptance testing - determining if software is satisfactory to an end-user or customer.
• comparison testing - comparing software weaknesses and strengths to competing products.
• alpha testing - testing of an application when development is nearing completion; minor design changes may still be made as a result of such testing. Typically done by end-users or others, not by programmers or testers.
• beta testing - testing when development and testing are essentially completed and final bugs and problems need to be found before final release. Typically done by end-users or others, not by programmers or testers.
• mutation testing - a method for determining if a set of test data or test cases is useful, by deliberately introducing various code changes ('bugs') and retesting with the original test data/cases to determine if the 'bugs' are detected. Proper implementation requires large computational resources.

Manual Testing Interview Questions and Answers 2

Why is it often hard for management to get serious about quality assurance?
Solving problems is a high-visibility process; preventing problems is low-visibility. This is illustrated by an old parable:
In ancient China there was a family of healers, one of whom was known throughout the land and employed as a physician to a great lord. The physician was asked which of his family was the most skillful healer. He replied,
"I tend to the sick and dying with drastic and dramatic treatments, and on occasion someone is cured and my name gets out among the lords."
"My elder brother cures sickness when it just begins to take root, and his skills are known among the local peasants and neighbors."
"My eldest brother is able to sense the spirit of sickness and eradicate it before it takes form. His name is unknown outside our home."

Why does software have bugs?
• miscommunication or no communication - as to specifics of what an application should or shouldn't do (the application's requirements).
• software complexity - the complexity of current software applications can be difficult to comprehend for anyone without experience in modern-day software development. Windows-type interfaces, client-server and distributed applications, data communications, enormous relational databases, and sheer size of applications have all contributed to the exponential growth in software/system complexity. And the use of object-oriented techniques can complicate instead of simplify a project unless it is well-engineered.
• programming errors - programmers, like anyone else, can make mistakes.
• changing requirements (whether documented or undocumented) - the customer may not understand the effects of changes, or may understand and request them anyway - redesign, rescheduling of engineers, effects on other projects, work already completed that may have to be redone or thrown out, hardware requirements that may be affected, etc. If there are many minor changes or any major changes, known and unknown dependencies among parts of the project are likely to interact and cause problems, and the complexity of coordinating changes may result in errors. Enthusiasm of engineering staff may be affected. In some fast-changing business environments, continuously modified requirements may be a fact of life. In this case, management must understand the resulting risks, and QA and test engineers must adapt and plan for continuous extensive testing to keep the inevitable bugs from running out of control - see 'What can be done if requirements are changing continuously?' in Part 2 of the FAQ.
• time pressures - scheduling of software projects is difficult at best, often requiring a lot of guesswork. When deadlines loom and the crunch comes, mistakes will be made.
• egos - people prefer to say things like:
'no problem'
'piece of cake'
'I can whip that out in a few hours'
'it should be easy to update that old code'
instead of:
'that adds a lot of complexity and we could end up
making a lot of mistakes'
'we have no idea if we can do that; we'll wing it'
'I can't estimate how long it will take, until I
take a close look at it'
'we can't figure out what that old spaghetti code
did in the first place'

If there are too many unrealistic 'no problem's', the result is bugs.

• poorly documented code - it's tough to maintain and modify code that is badly written or poorly documented; the result is bugs. In many organizations management provides no incentive for programmers to document their code or write clear, understandable, maintainable code. In fact, it's usually the opposite: they get points mostly for quickly turning out code, and there's job security if nobody else can understand it ('if it was hard to write, it should be hard to read').
• software development tools - visual tools, class libraries, compilers, scripting tools, etc. often introduce their own bugs or are poorly documented, resulting in added bugs.

How can new Software QA processes be introduced in an existing organization?
• A lot depends on the size of the organization and the risks involved. For large organizations with high-risk (in terms of lives or property) projects, serious management buy-in is required and a formalized QA process is necessary.
• Where the risk is lower, management and organizational buy-in and QA implementation may be a slower, step-at-a-time process. QA processes should be balanced with productivity so as to keep bureaucracy from getting out of hand.
• For small groups or projects, a more ad-hoc process may be appropriate, depending on the type of customers and projects. A lot will depend on team leads or managers, feedback to developers, and ensuring adequate communications among customers, managers, developers, and testers.
• The most value for effort will be in (a) requirements management processes, with a goal of clear, complete, testable requirement specifications embodied in requirements or design documentation and (b) design inspections and code inspections.

What is verification? validation?
Verification typically involves reviews and meetings to evaluate documents, plans, code, requirements, and specifications. This can be done with checklists, issues lists, walkthroughs, and inspection meetings. Validation typically involves actual testing and takes place after verifications are completed. The term 'IV & V' refers to Independent Verification and Validation.

What is a 'walkthrough'?
A 'walkthrough' is an informal meeting for evaluation or informational purposes. Little or no preparation is usually required.

What's an 'inspection'?
An inspection is more formalized than a 'walkthrough', typically with 3-8 people including a moderator, reader, and a recorder to take notes. The subject of the inspection is typically a document such as a requirements spec or a test plan, and the purpose is to find problems and see what's missing, not to fix anything. Attendees should prepare for this type of meeting by reading thru the document; most problems will be found during this preparation. The result of the inspection meeting should be a written report. Thorough preparation for inspections is difficult, painstaking work, but is one of the most cost effective methods of ensuring quality. Employees who are most skilled at inspections are like the 'eldest brother' in the parable in 'Why is it often hard for management to get serious about quality assurance?'. Their skill may have low visibility but they are extremely valuable to any software development organization, since bug prevention is far more cost-effective than bug detection.

MANUAL TESTING Interview Questions and Answers

What makes a good test engineer?
A good test engineer has a 'test to break' attitude, an ability to take the point of view of the customer, a strong desire for quality, and an attention to detail. Tact and diplomacy are useful in maintaining a cooperative relationship with developers, and an ability to communicate with both technical (developers) and non-technical (customers, management) people is useful. Previous software development experience can be helpful as it provides a deeper understanding of the software development process, gives the tester an appreciation for the developers' point of view, and reduce the learning curve in automated test tool programming. Judgment skills are needed to assess high-risk areas of an application on which to focus testing efforts when time is limited.

What makes a good Software QA engineer?
The same qualities a good tester has are useful for a QA engineer. Additionally, they must be able to understand the entire software development process and how it can fit into the business approach and goals of the organization. Communication skills and the ability to understand various sides of issues are important. In organizations in the early stages of implementing QA processes, patience and diplomacy are especially needed. An ability to find problems as well as to see 'what's missing' is important for inspections and reviews.

What makes a good QA or Test manager?
A good QA, test, or QA/Test(combined) manager should:
• be familiar with the software development process
• be able to maintain enthusiasm of their team and promote a positive atmosphere, despite
• what is a somewhat 'negative' process (e.g., looking for or preventing problems)
• be able to promote teamwork to increase productivity
• be able to promote cooperation between software, test, and QA engineers
• have the diplomatic skills needed to promote improvements in QA processes
• have the ability to withstand pressures and say 'no' to other managers when quality is insufficient or QA processes are not being adhered to
• have people judgement skills for hiring and keeping skilled personnel
• be able to communicate with technical and non-technical people, engineers, managers, and customers.
• be able to run meetings and keep them focused

What's the role of documentation in QA?
Critical. (Note that documentation can be electronic, not necessarily paper.) QA practices should be documented such that they are repeatable. Specifications, designs, business rules, inspection reports, configurations, code changes, test plans, test cases, bug reports, user manuals, etc. should all be documented. There should ideally be a system for easily finding and obtaining documents and determining what documentation will have a particular piece of information. Change management for documentation should be used if possible.

What's the big deal about 'requirements'?

One of the most reliable methods of insuring problems, or failure, in a complex software project is to have poorly documented requirements specifications. Requirements are the details describing an application's externally-perceived functionality and properties. Requirements should be clear, complete, reasonably detailed, cohesive, attainable, and testable. A non-testable requirement would be, for example, 'user-friendly' (too subjective). A testable requirement would be something like 'the user must enter their previously-assigned password to access the application'. Determining and organizing requirements details in a useful and efficient way can be a difficult effort; different methods are available depending on the particular project. Many books are available that describe various approaches to this task. (See the Bookstore section's 'Software Requirements Engineering' category for books on Software Requirements.)
Care should be taken to involve ALL of a project's significant 'customers' in the requirements process. 'Customers' could be in-house personnel or out, and could include end-users, customer acceptance testers, customer contract officers, customer management, future software maintenance engineers, salespeople, etc. Anyone who could later derail the project if their expectations aren't met should be included if possible.
Organizations vary considerably in their handling of requirements specifications. Ideally, the requirements are spelled out in a document with statements such as 'The product shall.....'. 'Design' specifications should not be confused with 'requirements'; design specifications should be traceable back to the requirements.
In some organizations requirements may end up in high level project plans, functional specification documents, in design documents, or in other documents at various levels of detail. No matter what they are called, some type of documentation with detailed requirements will be needed by testers in order to properly plan and execute tests. Without such documentation, there will be no clear-cut way to determine if a software application is performing correctly.
'Agile' methods such as XP use methods requiring close interaction and cooperation between programmers and customers/end-users to iteratively develop requirements. The programmer uses 'Test first' development to first create automated unit testing code, which essentially embodies the requirements.

What steps are needed to develop and run software tests?
The following are some of the steps to consider:
• Obtain requirements, functional design, and internal design specifications and other necessary documents
• Obtain budget and schedule requirements
• Determine project-related personnel and their responsibilities, reporting requirements, required standards and processes (such as release processes, change processes, etc.)
• Identify application's higher-risk aspects, set priorities, and determine scope and limitations of tests
• Determine test approaches and methods - unit, integration, functional, system, load, usability tests, etc.
• Determine test environment requirements (hardware, software, communications, etc.)
• Determine testware requirements (record/playback tools, coverage analyzers, test tracking, problem/bug tracking, etc.)
• Determine test input data requirements
• Identify tasks, those responsible for tasks, and labor requirements
• Set schedule estimates, timelines, milestones
• Determine input equivalence classes, boundary value analyses, error classes
• Prepare test plan document and have needed reviews/approvals
• Write test cases
• Have needed reviews/inspections/approvals of test cases
• Prepare test environment and testware, obtain needed user manuals/reference documents/configuration guides/installation guides, set up test tracking processes, set up logging and archiving processes, set up or obtain test input data
• Obtain and install software releases
• Perform tests
• Evaluate and report results
• Track problems/bugs and fixes
• Retest as needed
• Maintain and update test plans, test cases, test environment, and testware through life cycle

What's a 'test plan'?
A software project test plan is a document that describes the objectives, scope, approach, and focus of a software testing effort. The process of preparing a test plan is a useful way to think through the efforts needed to validate the acceptability of a software product. The completed document will help people outside the test group understand the 'why' and 'how' of product validation. It should be thorough enough to be useful but not so thorough that no one outside the test group will read it. The following are some of the items that might be included in a test plan, depending on the particular project:
• Title
• Identification of software including version/release numbers
• Revision history of document including authors, dates, approvals
• Table of Contents
• Purpose of document, intended audience
• Objective of testing effort
• Software product overview
• Relevant related document list, such as requirements, design documents, other test plans, etc.
• Relevant standards or legal requirements
• Traceability requirements
• Relevant naming conventions and identifier conventions
• Overall software project organization and personnel/contact-info/responsibilties
• Test organization and personnel/contact-info/responsibilities
• Assumptions and dependencies
• Project risk analysis
• Testing priorities and focus
• Scope and limitations of testing
• Test outline - a decomposition of the test approach by test type, feature, functionality, process, system, module, etc. as applicable
• Outline of data input equivalence classes, boundary value analysis, error classes
• Test environment - hardware, operating systems, other required software, data configurations, interfaces to other systems
• Test environment validity analysis - differences between the test and production systems and their impact on test validity.
• Test environment setup and configuration issues
• Software migration processes
• Software CM processes
• Test data setup requirements
• Database setup requirements
• Outline of system-logging/error-logging/other capabilities, and tools such as screen capture software, that will be used to help describe and report bugs
• Discussion of any specialized software or hardware tools that will be used by testers to help track the cause or source of bugs
• Test automation - justification and overview
• Test tools to be used, including versions, patches, etc.
• Test script/test code maintenance processes and version control
• Problem tracking and resolution - tools and processes
• Project test metrics to be used
• Reporting requirements and testing deliverables
• Software entrance and exit criteria
• Initial sanity testing period and criteria
• Test suspension and restart criteria
• Personnel allocation
• Personnel pre-training needs
• Test site/location
• Outside test organizations to be utilized and their purpose, responsibilties, deliverables, contact persons, and coordination issues
• Relevant proprietary, classified, security, and licensing issues.
• Open issues
• Appendix - glossary, acronyms, etc.

What is 'configuration management'?Configuration management covers the processes used to control, coordinate, and track: code, requirements, documentation, problems, change requests, designs, tools/compilers/libraries/patches, changes made to them, and who makes the changes. (See the 'Tools' section for web resources with listings of configuration management tools. Also see the Bookstore section's 'Configuration Management' category for useful books with more information.)

What if the software is so buggy it can't really be tested at all?
The best bet in this situation is for the testers to go through the process of reporting whatever bugs or blocking-type problems initially show up, with the focus being on critical bugs. Since this type of problem can severely affect schedules, and indicates deeper problems in the software development process (such as insufficient unit testing or insufficient integration testing, poor design, improper build or release procedures, etc.) managers should be notified, and provided with some documentation as evidence of the problem.

How can it be known when to stop testing? This can be difficult to determine. Many modern software applications are so complex, and run in such an interdependent environment, that complete testing can never be done. Common factors in deciding when to stop are:
• Deadlines (release deadlines, testing deadlines, etc.)
• Test cases completed with certain percentage passed
• Test budget depleted
• Coverage of code/functionality/requirements reaches a specified point
• Bug rate falls below a certain level
• Beta or alpha testing period ends

What if there isn't enough time for thorough testing? Use risk analysis to determine where testing should be focused.
Since it's rarely possible to test every possible aspect of an application, every possible combination of events, every dependency, or everything that could go wrong, risk analysis is appropriate to most software development projects. This requires judgement skills, common sense, and experience. (If warranted, formal methods are also available.) Considerations can include:
• Which functionality is most important to the project's intended purpose?
• Which functionality is most visible to the user?
• Which functionality has the largest safety impact?
• Which functionality has the largest financial impact on users?
• Which aspects of the application are most important to the customer?
• Which aspects of the application can be tested early in the development cycle?
• Which parts of the code are most complex, and thus most subject to errors?
• Which parts of the application were developed in rush or panic mode?
• Which aspects of similar/related previous projects caused problems?
• Which aspects of similar/related previous projects had large maintenance expenses?
• Which parts of the requirements and design are unclear or poorly thought out?
• What do the developers think are the highest-risk aspects of the application?
• What kinds of problems would cause the worst publicity?
• What kinds of problems would cause the most customer service complaints?
• What kinds of tests could easily cover multiple functionalities?
• Which tests will have the best high-risk-coverage to time-required ratio?

What if the project isn't big enough to justify extensive testing?
Consider the impact of project errors, not the size of the project. However, if extensive testing is still not justified, risk analysis is again needed and the same considerations as described previously in 'What if there isn't enough time for thorough testing?' apply. The tester might then do ad hoc testing, or write up a limited test plan based on the risk analysis.

What can be done if requirements are changing continuously?A common problem and a major headache.
• Work with the project's stakeholders early on to understand how requirements might change so that alternate test plans and strategies can be worked out in advance, if possible.
• It's helpful if the application's initial design allows for some adaptability so that later changes do not require redoing the application from scratch.
• If the code is well-commented and well-documented this makes changes easier for the developers.
• Use rapid prototyping whenever possible to help customers feel sure of their requirements and minimize changes.
• The project's initial schedule should allow for some extra time commensurate with the possibility of changes.
• Try to move new requirements to a 'Phase 2' version of an application, while using the original requirements for the 'Phase 1' version.
• Negotiate to allow only easily-implemented new requirements into the project, while moving more difficult new requirements into future versions of the application.
• Be sure that customers and management understand the scheduling impacts, inherent risks, and costs of significant requirements changes. Then let management or the customers (not the developers or testers) decide if the changes are warranted - after all, that's their job.
• Balance the effort put into setting up automated testing with the expected effort required to re-do them to deal with changes.
• Try to design some flexibility into automated test scripts.
• Focus initial automated testing on application aspects that are most likely to remain unchanged.
• Devote appropriate effort to risk analysis of changes to minimize regression testing needs.
• Design some flexibility into test cases (this is not easily done; the best bet might be to minimize the detail in the test cases, or set up only higher-level generic-type test plans)
• Focus less on detailed test plans and test cases and more on ad hoc testing (with an understanding of the added risk that this entails).

What's a 'test case'?

• A test case is a document that describes an input, action, or event and an expected response, to determine if a feature of an application is working correctly. A test case should contain particulars such as test case identifier, test case name, objective, test conditions/setup, input data requirements, steps, and expected results.
• Note that the process of developing test cases can help find problems in the requirements or design of an application, since it requires completely thinking through the operation of the application. For this reason, it's useful to prepare test cases early in the development cycle if possible.

What should be done after a bug is found?
The bug needs to be communicated and assigned to developers that can fix it. After the problem is resolved, fixes should be re-tested, and determinations made regarding requirements for regression testing to check that fixes didn't create problems elsewhere. If a problem-tracking system is in place, it should encapsulate these processes. A variety of commercial problem-tracking/management software tools are available (see the 'Tools' section for web resources with listings of such tools). The following are items to consider in the tracking process:
• Complete information such that developers can understand the bug, get an idea of it's severity, and reproduce it if necessary.
• Bug identifier (number, ID, etc.)
• Current bug status (e.g., 'Released for Retest', 'New', etc.)
• The application name or identifier and version
• The function, module, feature, object, screen, etc. where the bug occurred
• Environment specifics, system, platform, relevant hardware specifics
• Test case name/number/identifier
• One-line bug description
• Full bug description
• Description of steps needed to reproduce the bug if not covered by a test case or if the developer doesn't have easy access to the test case/test script/test tool
• Names and/or descriptions of file/data/messages/etc. used in test
• File excerpts/error messages/log file excerpts/screen shots/test tool logs that would be helpful in finding the cause of the problem
• Severity estimate (a 5-level range such as 1-5 or 'critical'-to-'low' is common)
• Was the bug reproducible?
• Tester name
• Test date
• Bug reporting date
• Name of developer/group/organization the problem is assigned to
• Description of problem cause
• Description of fix
• Code section/file/module/class/method that was fixed
• Date of fix
• Application version that contains the fix
• Tester responsible for retest
• Retest date
• Retest results
• Regression testing requirements
• Tester responsible for regression tests
• Regression testing results
A reporting or tracking process should enable notification of appropriate personnel at various stages. For instance, testers need to know when retesting is needed, developers need to know when bugs are found and how to get the needed information, and reporting/summary capabilities are needed for managers.

Measuring The System Capacity

How do we measure the system capacity?
We measure system capacity to find out how much excess capacity the system can handle without any degradation in its performance .
For checking the capacity of a system, we compare the performance versus load on the existing system, and find out a point at which significant degradation of response-time starts taking place. Point is known as "knee" when plotted over a response time curve.
What is the purpose of creating Scenarios in LoadRunner?
For testing a system by using LoadRunner, we need to create a scenario. Scenario is a file containing complete information about the testing session. The scenario is a means of emulating a real-life user.
The scenario contains following information about the mechanism of emulating the real users:
1) Details of groups of virtual users or Vusers.
2) Details of test scripts the Vusers will run.
3) Details of load generators upon which the scripts shall be made to run.
How many types of scenarios can be created while using Controller of LoadRunner?
We can create any one type of scenario out of the following:
1) Manual Scenario: Scenario is created manually by defining the number of Vuser groups we want to run, and building a schedule for LoadRunner to run these groups. Manual scenario can be created by defining the total number of Vusers to be used in the scenario, or assigning a percentage of the total number of Vusers to each script.
2) Goal-Oriented Scenario: We define the goals that we want to achieve in our test and LoadRunner automatically builds a scenario for us, based upon our goals.
How can we change the maximum number of scripts displayed in the Available Scripts list?
We can change the maximum number of scripts displayed in the Available Scripts list by modifying the registry key:
HKEY_CURRENT_USER\Software\Mercury Interactive\RecentScripts\max_num_of_scripts
What is the purpose of Scenario Files?
A scenario provides detailed description of various events taking place during every load testing session.
A scenario is created by using the Design view of Controller in LoadRunner. Once a scenario is created, LoadRunner saves the information in a
scenario file having an extension (*.lrs).
What methods are available in LoadRunner for building scenarios?
Two methods are available through which we can create scenarios.
1) Manual Scenario creation method: Involves creating groups and specifying the script, the load generator, and the number of Vusers included in each group. We can chose to opt for using Percentage Mode to distribute our Vusers among various scripts.
2) Goal Oriented Scenario creation method: Involves defining the goals we want our test to achieve, and LoadRunner automatically builds a scenario for us, based on these goals.
How can we change the maximum number of scripts displayed in the Available Scripts list?
We can change the maximum number of scripts displayed in the Available Scripts list by modifying the registry key:
HKEY_CURRENT_USER\Software\Mercury Interactive\RecentScripts\max_num_of_scripts
What is the purpose of having Vuser groups in scenarios?
A scenario consists of groups of Vusers which simulate the actions of human users on the application under test. When a particular scenario is run, the Vusers generate load on the server, and LoadRunner monitors the server and transaction performance..
Vuser groups are created to organize several Vusers in a scenario into manageable groups. Vuser groups are created by including Vusers having similar characteristics. For example, when many Vusers run the same Vuser script, we can club them into one Vuser group.
What type of actions can be performed on a Vuser group or scenario?
Following actions can be performed on a Vuser group:
1) Defining the group name, Vuser quantity, load generators, and scripts for the Vuser group.
2) Adding load generators to the Vuser group and configuring the load generators.
3) Adding and configuring scripts to the Vuser group.
4) Enabling or disabling a Vuser group for the scenario.
5) Removing a Vuser group from the scenario.
6) Scheduling the Vuser group execution.
7) Defining service level agreements for the scenario.
8) Running, stopping & resetting the scenario.
9) Configuring the settings of scenario results.
What is the meaning of pending status for a Vuser?

Pending status for a V user indicates that the Vuser is ready to be initialized and is waiting for an available load generator, or is transferring files to the load generator. The Vuser will run when the conditions set in its scheduling attributes are met.

What is the meaning of rendezvous status for a Vuser?
Rendezvous status for a Vuser indicates that the Vuser has arrived at the rendezvous and is waiting to be released by LoadRunner.
What is the purpose of Gradual Stop option for the Vusers?
Gradual Stop option Instructs the Controller to complete the current iteration or action before stopping the Vuser. This option is only available when the Vuser is in the RUN state.
How do we modify the run-time settings of multiple scripts?
We need to chose the method of modifying the run-time settings:
1) Modification method for Shared run-time settings: This method opens one window containing all of the run-time settings in blank mode. In this mode, we set only the options that we want to modify for all selected scripts. All other run-time settings remain unchanged.
Some of the run-time settings cannot be modified in shared mode. These settings do not appear. To modify them, we need to open the run-time settings for each individual script.
2) Modification method for Individual run-time settings: This method opens a separate window for each selected script. In this mode, we modify each script’s settings individually.
What configuration settings we can define for Load Generators in a scenario?
With the help of Load Generators dialog box, we can set following type of load generator’s attributes:
1) Defining which load generators will run Vusers in the scenario. For example, if a load generator is unavailable for a particular scenario run, we can exclude it temporarily instead of removing it entirely from your list of load generators.
2) Selecting which load generators will take part in the scenario by using the Enable and Disable commands. Disabling a load generator temporarily removes it from the list. Enabling a load generator reinstates it.
What is the role of controller in LoadRunner?
The Controller monitors a Windows load generator’s CPU usage and automatically stops loading Vusers on a load generator when it becomes overloaded.
We can monitor the status of a machine’s CPU usage. When the CPU usage of a load generator becomes problematic, the icon to the left of the load generator name contains a yellow bar. When the machine becomes overloaded, the icon contains a red bar.
What are the Terminal Services in LoadRunner?
Terminal services allows centralized management of computing resources for each client connected to the server, and provides each user with their own working environment.
We use LoadRunner’s Terminal Services Manager to remotely manage multiple load generators running in our load testing scenario on a terminal server. With the help of Terminal Services Manager, we can select the number of terminals to be used in our scenario & the maximum number of Vusers which can be run per terminal. The Terminal Services Manager then evenly distributes the number of virtual users among the client sessions.
With the help of Terminal Server Client, we can operate in a server-based computing environment from a remote machine. The terminal server transmits applications over the network and displays them via terminal emulation software. Every user logs on and sees only his individual session, which is managed transparently by the server operating system, independent of any other client session.
What is the use of Creating a Manual Scenario Using the Percentage Mode?
A manual scenario is created in the Percentage mode by defining the total number of Vusers to be used in the scenario, and assigning load generators and a percentage of the total number of Vusers to each script.
While creating a new scenario, we can access the Percentage Mode directly by selecting the "Use the Percentage Mode to distribute the Vusers among the scripts" in the New Scenario dialog box.
A scenario created in the Vuser Group Mode can be easily converted to the Percentage Mode.
What are the key considerations while converting a scenario from Vuser Group Mode to Percentage Mode?
1) In case we have defined multiple scripts for a Vuser group, the number of Vuser scripts created in the Percentage Mode will be same as the number of scripts defined for the group.
2) All Load Generators will be assigned to all Vuser scripts created in the Percentage Mode. In case we have defined multiple load generators for a Vuser group, the Vusers we assign to the scripts in the Percentage Mode will be distributed evenly among the load generators previously assigned by us to the group.
3) All Vuser group schedule settings will be lost. All profiles will contain scenario schedule settings only.
What are the key considerations while converting a scenario from Percentage Mode to Vuser Group Mode?
1) Each script will be converted to a Vuser group.
2) In case we have defined multiple load generators for a Vuser script, the Vuser group which is created when converting the scenario will also contain multiple load generators.
3) All schedule settings will be retained as it is.
What is the purpose of Scheduling Scenarios?
After creating a scenario, we schedule it to start running at a specified time. We can make a schedule defining the time at which to initialize, start, and stop Vusers during the scenario run, and how long an action should continue running.
We can restrict the execution duration of the scenario or of a Vuser group within the scenario. We can also stipulate how many Vusers to start and stop running within a certain time frame. We can specify whether LoadRunner should start or stop running all Vusers in a scenario simultaneously, or only a certain number of Vusers within a specified amount of time.
What is the effect of Rendezvous points on the running of scenarios as per schedule?
Rendezvous points, if present in a script, interfere with the scheduled scenario run. The scenario will not run as scheduled due to the presence of rendezvous points in the script.
What are the methods by which we can schedule the enabled Vuser groups in a scenario?
After creating a scenario, we can schedule the enabled Vuser groups to run according to either of the following:
1) As a part of a whole scenario: When we run a scenario, LoadRunner runs all the Vuser groups enabled in the scenario. The schedule defined for running the scenario is applied to all the Vuser groups concurrently, and LoadRunner applies each action proportionately to all the Vusers groups.
2) As per its own schedule: For each enabled Vuser group in a scenario, we can design a separate execution schedule. We can specify when to start running the Vuser group, how many Vusers to start and stop running within given time intervals, and how long the Vuser group should continue running.
How many modes are available to us for scheduling the running of scenario?
We can schedule a scenario to run in one of the following modes:
1) Real-life schedule: The scenario runs according to a user-defined group of actions that simulate a real-life schedule of events. Vuser groups run according to the iterations defined in their run-time settings, but we can define how many Vusers to run at a time, how long Vusers should continue to run, and how many Vusers to stop running at a time.
2) Classic Schedule: All enabled Vuser groups run together on one schedule, each according to its own run-time settings. We can schedule how many Vusers to start running at a time, how long to run the Vusers, and how many Vusers to stop running at a time.
3) Run until complete: All the Vuser groups in the scenario run according to the iterations defined in their run-time settings. Each Vuser group in the scenario runs its defined course, and when all the Vuser groups have finished running, the scenario run is complete.
What is the purpose of specifying Service Level Agreements in scenarios?
While creating a load testing scenario, we can specify our goals or service level agreements - SLA's for the performance measurement.
When this scenario is made to run the LoadRunner captures all the performance related data. During analysis phase, Analysis compares this data against the SLAs and determines SLA status for the defined measurements.
What methods LoadRunner uses to find out the SLA status?
Depending on the measurements being evaluated by us, LoadRunner finds out the SLA status in one of the following ways:
1) As per time interval within the run: Analysis displays SLA statuses at set time intervals in the timeline. For example, every 10 seconds - Analysis checks to see if the measurement’s performance has deviated from the threshold defined in the SLA.
2) As per the whole run: Analysis displays a single SLA status for the whole scenario run. The measurements include - Total Hits, Average Hits, Total Throughput, and Average Throughput.
How many types of Goal Oriented Scenarios can be created in LoadRunner?
In a goal-oriented scenario, we define the goals required to be achieved through our tests, and LoadRunner automatically builds a scenario for us based on these goals.
When we want to test how many Vusers the application can run simultaneously, it is better to define a type of goal for the Virtual Users.
Following five types of goals can be defined in a goal-oriented scenario:
1) Defined number of virtual users
2) Defined number of hits per second by the Web Vusers.
3) Defined number of transactions per second.
4) Defined number of pages per minute by the Web Vusers.
5) Defined transaction response time we want our scenario to reach.
Under what circumstances a Pages per Minute or Hits per Second goal-oriented scenario fails?
Pages per Minute or Hits per Second goal-oriented scenario is assigned a "Failed" status in situations like:
1) When the Controller has twice attempted to reach the goal using the maximum number of Vusers specified, and the goal could not be reached.
2) When no pages per minute or hits or transactions per second were registered after the first batch of Vusers was run.
3) When the number of pages per minute or hits or transactions per second did not increase after the Controller ran a certain number of Vuser batches.
4) When all the Vusers that were run failed.
5) When there were no available load generators for the type of Vusers we attempted to run.
What is Load Balancing process in LoadRunner?
Load balancing is the process, which evenly distributes the load generated by Vusers among the requested load generators, thereby ensuring an accurate load test.
When a Windows load generator’s CPU usage becomes overloaded, the Controller stops loading Vusers on the overloaded load generator, and automatically distributes them among load generators taking part in the scenario.
Load balancing option is available only in goal-oriented scenarios and manually controlled scenarios in the Percentage Mode.
What policy attributes can be defined for rendezvous points?
Setting the rendezvous policy determines how the Vusers handle a rendezvous point. We can set the following policy attributes for every rendezvous point:
1) Release policy: Defines how many Vusers will be released from a rendezvous point at a time.
2) Timeout policy: Defines how long the Controller shall wait before releasing Vusers from a rendezvous point.
Can we disable a particular Vusers at Rendezvous Points?
We can disable a rendezvous point for all Vusers in a scenario.
In addition to this we can disable a rendezvous point for a particular Vusers.
By disabling Vusers at a rendezvous point, we temporarily exclude them from participating in the rendezvous. Enabling disabled Vusers returns them back to the rendezvous.
What type of status related Rendezvous Information is available to us during creation of a scenario?
Following Rendezvous Information is available to us for viewing & necessary modifications:
1) Current Status: The number of Vusers that arrived at the rendezvous point out of the total number of Vusers assigned to the rendezvous.
2) Time: The time at which the Vusers at the rendezvous point were released.
3) Reason: The reason the Vusers at the rendezvous point were released. The possible reasons are Timeout or Arrived.
Out of Individual Load Generator settings & Global Settings, which ones come into effect?
When the global scenario settings differ from those of an individual load generator, the load generator settings override them.
What is the use of LoadRunner Expert mode?
We can configure additional settings for the LoadRunner agent and other LoadRunner components with the help of LoadRunner Expert mode.
How LoadRunner takes care of timeout value requirements in case of large number of Vusers?
LoadRunner automatically understands the fact that the number of active Vusers has a significant effect on the timeout values.
For example, 1000 Vusers trying to initialize will take much longer than 10 Vusers. Taking care of this, LoadRunner automatically adds an internal value, based on the number of active Vusers, to the timeout value specified by us.
While running a scenario, the run-time files are stored at which location by default?
While we run a scenario, by default the run-time files get stored locally on each load generator machine running the Vuser script.
The default location of the files is under the temporary directory specified by the load generator’s environment variables like Windows - TEMP or TMP Directory.
If no environment variable is defined, the files get saved to the /tmp directory.
What are the various types of Primary Run-time files?
Primary run-time files are of following types:
1) Vuser Script files: When we run a Vuser, the Controller sends a copy of the associated Vuser script to the Vuser load generator. These script files are stored in the load generator’s temporary run-time directory.
2) Result files: While we run a scenario, the participating Vusers write their results to the temporary run-time file directory. After scenario execution, these result files are consolidated and the results from all the load generators are transferred to the results directory.
How transfer of script files takes place at run time in case Vusers access the scripts at some shared location?
If we specify that all Vusers access their Vuser scripts directly at some shared location, no transfer of script files take place at run time.
What is Path translation in LoadRunner
Path translation is a mechanism used by LoadRunner to convert remote path names. We need to do path translation, when we specify a shared network drive for run-time file storage.
What preparatory steps are recommended for running a scenario?
Before running a scenario following are suggested steps:

1) Specify the location of the results.
2) Assign a name to the results.

3) Scheduling of the scenario.

4) Providing scenario summary information.

5) Specification of applications to be invoked at the start of the scenario.
What is the extension of scenario result file?
The general information about the scenario are stored in a result file with an extension (.eve and .lrr)