Top Performance Testing Interview Questions & Answers for 2020

Introduction

Software Performance testing is the type of testing performed to decide on the quality of the execution of the system which is under scrutiny to assess the measure, validation or confirm the quality properties of the framework like responsiveness, speed, scalability, stability under a varied variety of load conditions. The system is tested under a blend of load conditions and is checked for the time required for reacting by the system under changing workloads.

Performance testing engineers and workers are known to be some of the most joyful workers in America. Programming Testers are paid well, and their compensation averages around $75 to $100 K. This job profile can offer you long-term stability and security. Therefore to help you get that dream job in the performance testing field our experts have compiled a list of a few most expected questions in an interview on performance testing.

For the person who is looking to attend a performance testing interview anytime soon, here are the most commonly asked interview questions and answers to help you in the right way with your interview for the dream job of yours. Here, we have incorporated the most frequently asked questions along with pertinent answers to help freshers and experienced professionals in the field.

Performance Testing Interview Questions And Answers For Freshers

1). What is Performance testing?

Performance testing is a discipline of software testing wherein a tester tests the given system to assess the system’s performance when subjected to a variety of virtual user load. 

2). Name a few types of performance testing

There are primarily six types of performance testing. They are-

• Load testing
• Endurance testing
• Volume testing
• Stress testing
• Scalability testing
• Spike testing

3). Differentiate between Stress Testing and Load Testing?

Stress Testing is also known as negative testing as the tester test the system beyond its boundaries specified to discover the breakpoint threshold of the system. Whereas load testing is the easiest form of performance testing which is done by increasing the testing load step by step to reach the defined limit or the goal. 

4). What is concurrent user load in performance testing?

Concurrent user load in performance testing can be defined as something when many users hit any functionality or operation at the same time.

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5). What is a protocol and name a few protocols?

A protocol is defined as a set of various rules for the purpose of information communication between the two or more systems. There are many protocols such as Http/Https, FTP, Web Services, Citrix, Http/Https and Web Services.

6). Name a few common performance testing problems.

A few recurring performance testing problems are-

• Longer loading time
• Poor Scalability
• Bottlenecking
• Poor response time

7). Name a few common performance bottlenecks?

Some popular common performance bottlenecks are-

• CPU Utilization
• Memory Utilization
• Networking Utilization
• S limitation
• Disk Usage 

8). Name some popular performance testing tools?

Some common performance testing tools are-

• HP Loader
• HTTP Load
• Proxy Sniffer
• Rational Performance Tester
• JMeter
• Borland Silk Performer

9). What are the parameters considered for performance testing?

The parameters considered are-

• Memory usage
• CPU interruption per second
• Committed memory
• Thread counts
• Top waits, etc.
• Processor usage
• Network output queue length
• Response time
• Bandwidth
• Memory pages

10). Elucidate the steps that are required in JMeter to create a performance test plan?

To create a performance test plan in JMeter you need the following steps-

• Add thread group
• Add JMeter elements
• Add Graph result
• Run test & get the result

Performance Testing Interview Questions And Answers For Experienced 

11). List down the phases of automated performance testing?

Here is a list of phases for automated performance testing

• Design or Planning
• Build
• Execution
• Analyzing & Tuning

12). Differentiate between benchmark testing and baseline testing?

Benchmark Testing is the method deployed for comparing the performance of your system framework performance against a set industry standard that is laid out already by some other organization. Whereas the Baseline Testing is the type of testing technique where a tester runs a series of tests in order to get hold of the performance information. When any future change is made in the given app, this data is then used as a reference point.

13). What is performance tuning?

Performance tuning is a method or a mechanism followed to improve the system performance.

14). Name and elucidate the types of performance tuning.

In order to improve the performance of the system, primarily there are two types of tuning performed-

• Hardware tuning: Enhancing, adding or supplanting the hardware components of the system under test and changes in the framework level to augment the system’s performance is called hardware tuning.
• Software tuning: Identifying the software level bottlenecks by profiling the code, database etc. Fine-tuning or modifying the software to fix the bottlenecks is called software tuning.

15). Highlight the need for opting for Performance testing?

Performance testing is generally required to validate the below-given things:

• The response time of application for the intended number of users-
• Utmost load resisting capacity of an application.
• The capability of the app under test to handle the particular number of transactions.
• The constancy of an application under the usual and unexpected user load.
• Making sure that users have an appropriate response time on production.

16). What is the reason behind the discontinuation of manual load testing?

Following were the drawbacks of manual Load Testing that lead to the adoption of Automation load testing:

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• Complicated procedure to measure the performance of the application precisely.
• Complex synchronization procedures between the two or more users.
• Difficult to assess and recognize the outcomes & bottlenecks.
• Increased overall infrastructure cost.

17). In what manner would you identify the performance bottlenecks situations?

Performance Bottlenecks can be easily recognized by monitoring the app against load and stress conditions. To find bottleneck situations in performance testing the testers usually use Load Runner because it supports many different types of monitors like a run-time monitor, network delay monitor, web resource monitor, database server monitor, firewall monitor, ERP server resources monitor and Java performance monitor. These monitors, in turn, help the tester to establish the condition which causes an increase in the response time of the application. The capacity of the performance of the application is based on response time, throughput, hits per sec, network delay graphs, etc.

18). Is it possible to perform spike testing in JMeter? if yes how?

Spike Testing is conducted to comprehend what changes happen on the appl when the abruptly large number of users is either increased or decreased. Unexpected changes in the number of users by increasing or decreasing at a certain point of application and then monitoring the behavior of the app thereafter. In JMeter, spike testing can be achieved by using Synchronizing Timer. The threads are jammed by synchronizing the timer until a specific number of threads have been successfully blocked, and then release them at once thus creating large immediate load.

19). What is the throughput in Performance Testing?

Throughput in Performance testing is either the quantity of data sent by the server in response to the client request in a particular given period of time or it is the specific number of units of work that can be handled in per unit of time. The throughput is calculated in terms of requests received per second, calls per day, reports per year, hits per second, etc. In the majority of the cases, the throughput is premeditated in bits per second. 

20). What is profiling in performance testing?

Profiling is a procedure of pinpointing a bottleneck performance at miniature levels. This is done by presentation teams for manufacturing which mainly includes developers or performance testers. You can profile in any application layer which is getting tested. If you want to do application profiling you may require utilizing tools for performance profiling of application servers.