JMeter Top most asked Interview Questions | JMeter refresher by Raghav Pal |

Video Description

JMeter Complete Course - https://youtu.be/SoW2pBak1_Q 00:00 Start 00:39 What is JMeter 01:17 Features of JMeter 02:52 How to setup JMeter on windows & mac os 06:53 Overview of GUI & Features 08:21 How to prepare for a Performance Test 12:51 Test Plan 14:10 Thread Group 16:21 Controllers 16:39 Samplers 18:30 Logical Controllers 19:27 Listeners 23:52 Command Line 26:13 Assertions 28:19 Config Elements 30:04 Timers 32:40 Pre-Processors & Post-Processors 33:37 Test Fragment 34:23 Non-Test Elements 35:36 Execution Order 36:54 Best Practices #JMeterMostAskedInterviewQuestions Module & Include Controller - https://youtu.be/jKiZ1efpE5w Config Elements 1 - https://youtu.be/F8q61fu2nJM Config Elements 2 - https://youtu.be/nEPeVA8bjU8 What is JMeter: Tool or Application for performance testing Free & Open Source Built with Java Features of JMeter: Completely free for performance testing of a variety of applications Web | API | FTP | DB | LDAP Option for Recording Inbuilt components for adding assertions & reporting Extensible using plugins JMeter is a server-side performance testing tool How to setup JMeter: 1 - Check java is installed java -version 2 - Download JMeter 3 - Unzip 4 - Start JMeter bin/jmeter.bat (win) bin/jmeter.sh (mac/linux) Overview of GUI & Features How to prepare for a Performance Test: Get approvals & authorizations Application & Environment Requirements for the test - What to test, Scenarios Test Data Expected behaviour or performance OR Baseline Reporting Format Test Plan: is a like a project where all the elements of the performance test are added It saves as a .jmx file Inside JMeter the Test Plan stores & displays the elements of the test in a tree view A minimal test will consist of the Test Plan, a Thread Group & one or more Samplers Thread Group: A Thread Group is a collection of threads Every JMeter test plan starts with this element Each thread represents one user using the application under test In a thread group element, we can define the No of users (threads) Ramp up & down Loops / iterations Controllers: JMeter has two types of Controllers - Samplers & Logical Controllers Samplers: Tell JMeter to send requests to a server & wait for a response They are processed in the order they appear in the tree Each sampler (except Flow Control Action) generates one or more sample results Logical Controllers: determine the order in which Samplers are processed let you customize the logic that JMeter uses to decide when to send requests Listeners: Components that show the result of the samplers Tree | Table | Graphs also provide means to view, save, read saved test results Listeners are processed at the end of the scope in which they are found Listeners can use a lot of memory if there are a lot of samples To minimize the amount of memory needed, use the Simple Data Writer Command Line On cmd prompt Goto the location of JMeter bin folder jmeter -n -t “location of imx file” -l “location of result file csv” Assertions: Assertion = Check or Validation Check Actual = Expected processed after every sampler in the same scope Config Elements: to set up defaults & variables for later use by samplers processed at the start of the scope in which they are found, i.e. before any samplers in the same scope Timers: to add delay (pause) before sampler request By default, JMeter thread executes samplers in sequence without pausing If more than 1 timers are used in Thread Group, JMeter will take the sum of the timers to pause can be added as children of samplers or controllers Pre-Processors: executes prior to a Sampler Request modify the settings of a Sample Request Or update variables Post-Processors: executes after a Sampler Request to process the response data, to extract values from it Test Fragment: special type of controller used with the Include Controller & Module Controller not executed unless it is referenced by either a Module Controller or an Include_Controller. This element is purely for code reuse within Test Plans Non-Test Elements: HTTP Mirror Server HTTP(s) Test Script Recorder Property Display Execution order: Configuration elements Pre-Processors Timers Sampler Post-Processors (unless SampleResult is null) Assertions (unless SampleResult is null) Listeners (unless SampleResult is null) Best practices 1. Always do performance testing on a separate env - not used for other activities 2. Run your tests with the same infrastructure, network stats etc. - consistent results | compare with baseline 3. Create more realistic test - add think time 4. Add some ramp up, Do not start directly with 1000 users 5. Always have a baseline to compare your test 6. JMeter checks the server performance & does not care for browser render time 7. Focus on the areas that need performance testing based on user scenario 8. Always document your results Share this with everyone If my work has helped you, consider helping an animal near you, in any way you can Never Stop Learning Raghav