Performance Testing & Load Runner

Performance Testing:

Performance testing is the process of determining the responsiveness or effectiveness or scalability and stability of software or device to determine how the components of a system are performing with given a particular state.

It can also serve to investigate, measure, validate or verify other quality attributes of the system, such as scalability, reliability and resource usage.

It includes: Load Testing, Stress Testing, capacity testing, volume testing, endurance testing, spike testing, scalability testing and reliability testing etc.

This type of testing does not give pass or fail result, it performed to get benchmark & standard of the application against Concurrency / Throughput, Server response time, Latency, Render response time etc. for responsiveness, speed, scalability and stability characteristics.

Load Runner has 4 key components

1. Virtual User Generator (VUGEN)

VUGEN is used for generating and editing scripts

It has four components

1)    Record

2)    Run

3)    Debug

4)    Design

2. Controller

Controller is where we apply the load. The Controller systematizes drives, manages and monitors the load test.

3. Load Generator

Load Generate is local CPU which generates the load by running virtual users

4. Analysis

Analysis accumulates logs from various load generators and present reports for visualization of run result data & monitoring data

Load Runners shows error details as below.
1) Syntax error: [ , ; : “ ) ] etc.
2) Runtime error: Spelling error.
3) Compiling error:

Advance Components

·         Parameterization

Replacing the recorded value with a script value.The value that you are replacing has to be in the database

          Parameterization helps

1.    Reducing script size

2.    Avoiding cache effect

·         Correlation

Using “Correlation” we can capture the dynamically generated value from the server using nested queries.

·         Load Balancing

How to increase/decrease the load

·         Think time

Think time is the time that a real user waits/ pause between actions.

·         Rendezvous Point

Rendezvous Points means “meeting points”. This option used to check the peak load from off peak load. Virtual users instructed/configured to wait during test execution for multiple Vusers to arrive at a certain point before execution