Performance Testing - Introduction

Performance Testing - Introduction

Performance testing is performed to determine product behaviour under various workload conditions and identify feature improvement over previous versions. Its main purpose is to monitor product responsiveness, scalability and throughput under different workload environment.

Why to do Performance Testing?

Goal of performance testing is not to find defects in the application, its main goal is to set benchmark and standard behaviour for the application.

More reasons for conducting performance testing:

• Identify throughput of the application
• Identify system tuning for better performance
• Find the source of performance problems
• Identify application behavior under multiple systems or in different system configurations

Different performance testing techniques:

• Performance Test- A performance test is any test that measures stability, performance, scalability and/or throughput of application.
• Load testing - Testing conducted to understand the behavior of the application under a specific load.
• Stress testing - It is executed to find the upper limit capacity of the system.
• Capacity Testing - This tests how many users/concurrent transactions your application can handle without losing performance benchmark.
• Soak/Endurance testing - It is performed to determine the system performance under continuous expected load. During soak tests the parameters such as memory utilization is monitored to detect memory leaks or other performance issues.
• Spike testing - In this testing number of concurrent users using application is increased suddenly by a very large amount and measuring the performance of the system. Aim of this testing is to find if the system will be able to sustain the workload.
• Smoke Testing - This testing is done to determine application behavior under very low load. If the test fails and no further testing is necessary until the simplest test passes successfully.

Performance Testing Tools:

• Apache Jmeter
• HP LoadRunner
• Web Load
• Rational Performance Tester
• NeoLoad
• CloudTest
• LoadUI

Image Reference:

https://leantesting.com/resources/how-to-prepare-your-app-for-load-testing/

http://softwareqaservices.com/performance-testing/

http://p3lang.com/2015/12/performance-testing-introduction/

Let QTP monitor your application's performance

While working with our applications, we see our application's performance going down on performing a particular action. Reasons for this might be different. We mainly see these kind of issues when resources reach its capacity. Resources can be CPU resources, memory, application, physical disk and network resources. So, finding these kind of bottlenecks is difficult in manual testing. If you are using QTP to automate your testing, then you have a solution for this.

Ref: http://goo.gl/FXePGx

QTP provides a functionality called Local System Monitoring. Enabling this functionality for a particular script lets QTP monitor and record resource usage for each and every step performed. Finally, it shows a graph with resource usage statistics. When a particular step is selected in result, corresponding resource stats will be shown in graph. So that, it would be easy to know on which action in application, performance is going down and the reason for this (memory leak/thread leak/gdi object count, etc..). In addition, you can export data from the System Monitoring tab for a variety of file types.

Following are few simple steps which need to be performed to monitor system counters:

• Enable Local System Monitoring from File->Settings->Local System Monitor.
• Provide the name of the application to be monitored.
• Add system counters to be monitored. We can even set limit to system counters. So that whenever a particular counter reaches the limit, your test run will fail.    
•  Once test run completes, result page will shows system monitor graph.

These statistics can be exported to any type of file for further investigation.