Jmeter

                                 JMeter is a Java based desktop application that can be used for performance testing of different kinds of client-server applications like websites, web services, databases, FTP servers etc. It is an open source tool provided by Apache without licensing cost.

The following types of applications that can be tested by Jmeter

• Websites - HTTP and HTTPS
• Web Services - REST and SOAP
• Database Servers
• FTP Servers
• LDAP Servers
• Mail Servers - SMTP, POP3, IMAP
• Shell Scripts
• TCP Servers

JMeter simulates a group of users sending requests to a target server, and return statistics that show the performance/functionality of the target server / application via tables, graphs etc. The figure below depicts this process:

Advantages of JMeter

1. Free of cost- It is an open source product with zero licensing cost.
2. Can load test different kinds of- It can be used for performance testing of all kinds of applications ranging from - Web applications, web services, database, LDAP, shell scripts etc.
3. Platform independent- As JMeter is 100% Java based, so it is platform independent and can run in multiple platforms.
4. Record and Playback feature- JMeter provides record and playback option along with drag and drop feature which makes it easier and faster to create scripts.
5. Customizable- Since JMeter is open source, developers can customize its source code as per their specific requirements.
6. Supports distributed load testing- JMeter supports distributed load testing feature in which we can create master-slave setup for carrying out load test on multiple machines.
7. Good community support- JMeter has many online tutorials and helping community support. It also has freely available plugins that help in different aspects of script creation and analysis.

Jmeter Download & Installation

To install or rather setup JMeter on Windows, Linux and Mac. Since JMeter is Java based, so it runs all the operating systems that are Java compliant. Just make sure your machines has latest version of Java (JVM) installed.

For Windows Machines

> How to download Jmeter:

To download jmeter we have to access to the following url from web

http://jmeter.apache.org/download_jmeter.cgi

step 1: Download the JMeter binary - "apache-jmeter-{version}.zip" from Binaries section

> How to Install Jmeter:

step 2:Unzip the JMeter binary to a directory where we want JMeter to be installed.

Step 3: Now we can launch JMeter by double clicking the jmeter.bat file inside the bin folder.

For linux Machines

> How to download Jmeter:

To download jmeter we have to access to the following url from web

http://jmeter.apache.org/download_jmeter.cgi

srep 1: Download the JMeter binary – "apache-jmeter-{version}.tgz" from Binaries section

> How to Install Jmeter:

step 2:Extract the binary to a directory where we want JMeter to be installed.

Step 3: Now we can launch JMeter by executing(double clicking) the jmeter.sh file inside the bin directory.

How to run jmeter :

Irrespective of machines we can run jmeter in two ways . Those are one is GUI mode and second one is Non-GUI mode.

For GUI mode just follow above steps to run jmeter.

For Non-GUI mode we have to run from command prompt (Windows) / Terminal (linux).

The following are the advantages if we run the jmeter in non-gui mode.

1. Increasing threads (after certain limit) due to which JMeter crashes in the GUI mode.
2. For heavy test scenarios (ex: shopping application: login-view product-add to cart-view bill-remove product-pay bill) JMeter consumes memory and CPU and it may affect your test results.
3. To increase JMeter capabilities, i.e. to get more requests per second.

Running JMeter in command line mode: (windows)

Running JMeter using command line in non-GUI mode is very simple.

1. Open command prompt
2. Go into JMeter’s bin folder
3. Enter following command, jmeter -n –t test.jmx -l testresults.jtl

JMeter has several parameters that can be used for running in the non-GUI mode.

-n: It specifies JMeter is to run in non-gui mode

-t: Name of JMX file that contains the Test Plan

-l: Name of JTL(JMeter text logs) file to log results

-j: Name of JMeter run log file

-R: list of remote servers

-H: proxy server hostname or ip address

-P: proxy server port

Once the test got completed to see the test results from “.jtl” file , follow the following steps.

1. Open JMeter in GUI mode.
2. Add any listener Eg. View Results Tree.
3. Click Browse button of the file name field in listener.
4. Open testresult.jtl file.
5. You should be able to see the result in listener now.

Running JMeter in command line mode: (Linux)

Step 1: open the terminal and eneter the command

for understanding perpouse i am giving two ways of commands

simple command:

jmeter -n -J jmeter.save.saveservice.timestamp_format="yyyy/MM/dd HH:mm:ss" -t AFCS_UPDATED.jmx -l result.jtl

complicated command:

/home/madhusudhana/Desktop/apache-jmeter-5.1.1/bin/jmeter -n -Jjmeter.save.saveservice.timestamp_format="yyyy/MM/dd HH:mm:ss" -JAFCS.Threads=100 -JAFCS.RampUp=60 -JAFCS.Duration=900 -JLoop_Controller_login=1 -JLoop_Controller_update_ticket=1 -JLoop_Controller_update_location=1 -t /home/madhusudhana/Desktop/Updated_AFCS/AFCS_UPDATED.jmx -l Chatak_AFCS_23_MAY_Duration_15min_100TC_60R_1.jtl

Note:

• To open the jmeter from terminal we have to enter the path where is the jmeter file is available: (the path)

/home/madhusudhana/Desktop/apache-jmeter-5.1.1/bin/jmeter

• -n --------- indicates that executing in non gui mode
• time stamp format (same for all the scripts)------------------- J jmeter.save. saveservice.timestamp_format="yyyy/MM/dd HH:mm:ss"
• -t ------------------ we have to enter the name and path of jmeter jmx file (AFCS_UPDATED.jmx)
• -l --------------------- we have to enter the name and path of .jtl file where jmeter need to save the jtl file.

Test plan :

A Test Plan is a logical container that contains different requests or operations required to create a performance test script. The different types of operations are carried out by different elements of the Test Plan. Using JMeter GUI for adding, removing and configuring the Test Plan elements.

The following are the few of the commonly used test plan elements

1. Thread Group
   Thread Groups are used to simulate virtual users in a performance test. We can have multiple thread groups simulating different types of operations performed by users on an application.
2. Sampler
   Samplers are the different requests which we can send to the server being tested. JMeter provides us various samplers like - HTTP, FTP, TCP, JDBC etc request samplers.
3. Logic Controllers
   Logic controller allow us to customize the way the Sampler requests is sent to the server. A common example of Logic Controller is Loop controller which makes a request multiple times to the server.
4. Timers
   Timers are used to halt the test execution for specified duration. Basically we use Timers to simulate real user wait Time or think time.
5. Assertions
   Assertions are used to perform some validations to check the correctness of the response received from the server.
6. Listeners
   Listeners in JMeter are used to save, view and analyze the test results in graphical or tabular forms.
7. Config elements

Config elements in JMeter are used to configure or modify the sampler requests made to the server. These elements are added at the same or higher level of the samplers that we want to configure.

Note : The test plan should have atleast one thread group.

Thread Group:

A Thread Group in JMeter represents a pool of virtual users performing a set of operations. For example, considering Google search scenario, one set of users will be using the search by text functionality, others will be using News Search, some other smaller section of users might be using search by image functionality. While creating a performance test script, for all these users, we will create different Thread Groups in JMeter with different thread count. The different types of Samplers like HTTP requests are added as child of these Thread Group elements to simulate the requests made by users to the server.

To launch the Thread Group in JMeter by following the path-

step 1: Right Click on Test Plan

step 2: choose Threads(Users)

step 3:Click Thread Group

After performing those steps we can see the following interface

Thread Group Properties

The Thread Group element has a control panel(right pane) that can be use to configure the various parameters in a performance test like - number of virtual users to generate, scheduling of the test, introducing of delays in the test etc.

Name - This is the name of the Thread Group, signifying the action performed by the virtual users e.g. if a Thread Group is scripted to perform login operation then we can have Thread Group name as 'LoginUsers'.

Comments - This is basically an optional textbox, that should contain the description of the action performed by the Thread Group or any other metadata information.

Configurations inside the "Action to be taken after a Sampler Error" block are used to configure the test for actions performed in case of any sampler error, because of no response from server or any assertion error-

1. Continue - In case of sampler error the test should continue.
2. Start Next Thread Loop - The test continues with next thread execution.
3. Stop Thread - The current thread gets stopped in case of error.
4. Stop Test - The thread is stopped gracefully, completing the current sampler request.
5. Stop Test Now - Abrupt stopping of thread in case of any error.

Configurations inside the "Thread Properties" block-

1. Number of Threads(users) - The number of virtual users to be simulated.
2. Ramp-up Period(in seconds) - The total amount of time taken to get all the thread started. For example - if we want each thread to be active in 0.5 seconds and there are total of 50 threads, then Ramp Up time should be 50*0.5 i.e. 25 seconds. We will see the benefit of using Ramp-Up period in our coming posts.
3. Loop Count- This is the count of the number of loop iteration performing a set of operations defined inside a thread group.
4. Loop Count Forever- When checked, it disables or overrides the loop count value and causes the loop to run infinitely until manually stopped.
5. Delay Thread Creation until needed - This is used to delay the thread creation till a value specified in this field(in seconds).
6. Scheduler - When checked, the scheduler configurations are enabled(explained below) and considered for scheduling of test at a particular time. Otherwise, the test run as soon as we run the test.

Configurations inside the "Scheduler Configuration" block-

1. Duration(seconds) - Duration specifies the duration of the test, once reached the test stops.
2. Startup delay(seconds) - On running a Test Script, JMeter will wait for the startup delay specified.
3. Start Time - This field is used to specify an absolute value of system time for starting the test, once the test is run. It is considered only if the above 'Duration' field is empty.
4. End Time - This field is used to specify an absolute value of system time for ending the test. It is considered only if the above 'Duration' field is empty.

Note:

To run the jmeter in non-gui mode we have to do parametrization for ramp-up , ramp-down , duration .

For example :

number of threads---------------------${__P(Threads,50)}

ramp-up --------------------------------${__P(RampUp,5)}

duration---------------------------------${__P(Duration,120)}

(while writing command to execute jmeter script in non- gui mode we have to use like J Threads=100  , J RampUp=60 , J Duration =120 )

Samplers

Samplers in JMeter are added as child of Thread Groups. These are used to send different types of request to server. Once, the sampler request is processed by the server, its response is returned to JMeter and the same can be viewed and analyzed in terms of different performance parameters like response time, Hits per second, throughput etc.
We can launch the Samplers in JMeter by following the path-

step 1 : Right Click on Thread Group

step 2: navigate to Add Sampler

step 3 : Click on the required Sampler

We have many samplers but in real time we will use only few samplers .

So Now we will disucuss about those samplers. Those are

HTTP Request - Used to send HTTP/HTTPS requests to server. This is the most widely used sampler for testing Web based applications.

JDBC Request - Used to send SQL queries to a database server.

SOAP/XML-RPC Request - Used to send SOAP requests to a SOAP web service.

Flow control Action - This is special type of Sampler, which doesn't send a request to the server instead it is used to introduce pauses in a test.

FTP Request - Used to send file put and get requests to an FTP server.

Apart from the above defined samplers, there are additional list of samplers provided by Jmeter- AJP/1.3 Sampler , Access Log Sampler , BSF Sampler ,BeanShell Sampler , Debug Sampler , JMS Point-to-Point,JMS Publisher ,JMS Subscriber,JSR223 Sampler,JUnit Request, Java Request,LDAP Extended Request,LDAP Request,Mail Reader Sampler,OS Process Sampler ,SMTP Sampler,TCP Sampler ,Test Sampler , WebService (SOAP) Request

In case If are selected the sampler as HTTP request then interface look like the following screenshot.

Configeration inside of HTTP request with an example:

Now i am going to build a HTTP request for one API.

API is : http://192.168.0.181:9080/coreservice/afcservice/core/1/0/createPTO

The body of the above API is

{

"name": "PTO Name",

"organizationName": "RIL",

"organizationId": "01",

"email": "pto@girmiti.com",

"state": "Karnataka",

"city": "Bangalore",

"country": "Indian",

"contactDetails": {

"name": "ABCD",

"phone": "+9198459845",

"email": "contact@girmiti.com"

},

"siteURL": "http://www.test.com",

"status": "<Opional>"

}

On successful request, the API would return the below response

{

"statusCode": "0",

"statusMessage": "SUCCESS",

"ptoId": "01"

}

Now we will see how to build the HTTP request .

Before going to build the request validate that API in postman tool either it is returing the expected output or not.

step 1: open jmeter

step 2 : change the name to test plan or keep the same

step 3 : right click on test plan and add thread group

step 4 : now right click on thread group and choose sampler as HTTP request.

Now the above screen shot will appear to you.

Name : you can enter any meaning ful name

comment : u can enter any or you can leave

Protocol (HTTP) : If you are following http then leave the box empty ifnot enter https in the box.

IP Address : 192.168.0.181 ( see above API )

port name: 9080

method : identify the method name from postman for the perticular API

path : /coreservice/afcservice/core/1/0/createPTO

Parameters : If you want to declare or pass any name / passwords you can pass from here.

Just hit on add tab at the bottom and add as you required.

Body data: copy the body data of the request from the postman and peaste the same hitting on body data.

Files upload: If you wanna upload any files you can upload here.

Logic Controllers

Logic Controllers are the Test Plan elements that are used to customize the order of processing of Samplers and other elements added as child. Primarily, Logic Controllers are used with Sampler requests to perform various customization like - altering their order of processing, grouping them as a single transaction or running the requests in loop etc.

Steps to launch a Logic Controller-

step1 : Right Click on Thread Group

step 2: Hover over Add -> Hover Over Logic Controllers

step 3: Click on the required Logic Controllers

you can also refer the following screenshot

what is the need of logic controllers in jmeter is Performance test scripts are used to simulate the actions of real users. Just like a real user will perform multiple actions in different fashion like perform a set of operations sequentially(e.g. navigate from login page to home page), perform similar types of operations in a loop(e.g. reading multiple unread mails), perform some random operations etc. For simulating these different types of actions, JMeter provides us different types of Logic Controllers which customize the element processing inside them.

Critical Section Controller

This is a newly added controller in JMeter. It ensures that the child elements of this controller are accessed by only one thread at a time.

ForEach Controller

This controller is used to perform the requests in loop, based on the values of a set of related variables.

If Controller

Using If Controller, we can specify a condition whether the child element inside it will run or not based on a condition which should evaluate to true or false.

Include Controller

The Include Controller can be used to provide modularity in JMeter. Using this controller we can add an external .jmx file(a test fragment) to our existing script by loading the jmx file in the Include Controler's control panel.

Interleave Controller

Interleave Controller allow us to pick and execute a single child element out of multiple child in each loop iteration. For example- if we have three samplers added as child to an Interleave Controller than the in first iteration it will pick the first sampler request, in next iteration it will pick the next one and so on. Once the child elements are over, it again starts iteration from first element.

Loop Controller

It allows to execute the operations specified as child elements in a loop with iteration value specified in its control panel.

Module Controller

Using Module Controller, we can reuse a test fragment(e.g. a sampler) into our script again by selecting the module from the Module Controller's control panel.

Once Only Controller

The once only controller is used in situation where we would like to perform an operation only once even if the operation is executed in a loop.

Random Controller

It is similar to random controller and picks a single child element in each iteration but unlike Interleave controller it picks the child element randomly.

Random Order Controller

The Random Order controller is used to execute each of its child element at most once in a random order.

Recording Controller

This controller acts as a placeholder where the scripts recorded using HTTP Proxy Server are recorded by default.

Runtime Controller

Runtime controller is used to limit the time of execution of its child elements. For example, if we have specified the value of 'Runtime' as 100 seconds then the elements inside the Runtime controller will run for 100 seconds with as much iteration as possible.

Simple Controller

This controller is just a placeholder for grouping and ordering the different elements of test plan.

Switch Controller

This controller is used to pick one element for processing out of its multiple child elements. The element are picked not in sequential order or random order instead it is based on a switch value defined in its control panel. The switch value can be an variable with value evaluated to its index(position) of the element or name of the element. For example, if in first iteration the switch value is evaluated to '3' then the fourth element is picked for processing(index value starts from 0). Similarly, if switch value is evaluated to an element's name then that element is picked for processing.

Throughput Controller

The Throughput Controller is used to control the processing of its child elements in terms of the total number of executions or the percentage of execution specififed in its control panel.

Transaction Controller

The Transaction Controller is one of the widely used controller in JMeter scripts. It is used to group multiple sampler requests into one. The response time and other performance metrics of the test result are evaluated for the whole transaction. For example - while checking performance of home page of an application, we can notice that launching the home page generates numerous requests at the backend. Hence, this requires grouping all these request into one transaction, for this we have transaction controller in JMeter. Once we run the script, we can find the overall response time of the whole transaction.

While Controller

The While controller is used to run the child elements inside it till the value specified in its control panel is evaluated to false.

Listeners

Listeners are the test plan elements that are used to view and analyze the result of performance tests in tabular or graphical form. They also provide the different response time metrices (average time, minimum time, max time etc) of a Sampler request.

How to add a Listener-

step 1: Right Click on Test plan

step 2: Listener and choose the required Listener

you can see the screenshot below for your reference.

                   We can add listeners as child of a particular Thread Group also. In that case, the Listener will use the data of that Thread Group for analysis.

Aggregate Graph

The Aggregate Graph listener is used to display the test results in both tabular form(reports) and graphs.

Aggregate Report

The Aggregate Report listener is used to display and store test results in the form of reports.

Assertion Results

The assertion results listener is used to display the assertion result for each erroneous sampler response. It is advised to not use this listener during performance test as it is very resource intensive. It should be used while debugging and functional testing only.

Backend Listener

The backend listener is a special type of asynchronous listener used specifically with BackendListenerClient for its customization.

BeanShell Listener

The beanshell listener is used to enable beanshell scripting in Jmeter.

BSF Listener

The beanshell listener is used to enable BSF scripting in Jmeter.

Comparison Assertion Visualizer

The Comparison Assertion Visualizer is used to provide the comparison between assertion result in an easy to compare UI.

Generate Summary Results

The Generate Summary results listener is used to store and display detailed test results to log files.

Graph Results

The Graph results listener is used to display each sampler request's response time graph in terms of average, median, deviation and throughput.

JSR223 Listener

The JSR223 Listener is used to enable JSR223 scripting in Jmeter.

Mailer Visualizer

The Mailer Visualizer sampler is used to provide the functionality of sending customized mails in case of some specific error threshold.

Monitor Results

This is a newly added listener in JMeter used to display and store server performance stats.

Response Time Graph

The response time graph is used to provide the graphical representation of response time with time elapsed during the test run.

Save Response to a file

The save response to a file listener is used to store the sampler response in a file. This listener is used while functional testing or debugging the test script.

Simple Data Writer

The simple data writer listener is used to save the sampler response to a file after with different configurations to remove several unnecessary overheads.

Summary Report

The summary report is used to store and display the test result in tabular form just like aggregate report listener but consumes less memory(as per Apache Jmeter).

View Results Tree

This listener is used to provide and store test results for each and every individual sampler.

View Results in Table

The view results in table listener is used to display the sampler response header and response body.

Among those listeners commonly used listners are view reult ,summary report , aggregate and beanshell.

Timers

Timers are the test plan elements used to pause the execution of test for a certain specified amount of time. This pause between requests helps in simulating real-world scenarios like time taken by users to think, type something, see and process the information displayed etc.

How to add a Timer-

step 1:Right Click on Thread Group

step 2: choose Add and select the Timer Click on the required Timer

From the following screenshot you can see the same.

           Types of timers available in jmeter are Beanshell timer , BSF timer,constant throughput timer,constant timer,gaussion random timer,JSR223 timer ,poission random timer , random timer ,random order timer and synchronizing timer.

Constant Timer

The constant timer is one of the most widely used timers in JMeter. It pauses the execution of test for a specified constant amount of time.

Uniform Random Timer

The uniform random timer is used to pause the test execution for a random time. The maximum value for random time can be specified along with the additional constant time with each wait.

Constant Throughput Timer

The constant throughput timer is a special type of timer used to create pauses with variable amount of time while maintaining the overall throughput i.e. samples/minute.

BeanShell Timer

The beanshell timer is used to generate the delays using beanshell scripting.

BSF Timer

The BSF timer is used to generate the delays using BSF scripting.

Gaussian Random Timer

The Gaussian random timer is used to generate the delays using Gaussian distribution.

Synchronizing Timer

The Synchronizing timer is used to insert delays in script by bocking a certain number of threads and when the blocked thread count reaches a specified number then the threads are released at once. Since, the synchronizing timer generates large amount of instant load hence, it is used for spike testing.

Poisson Random Timer

The Poisson random timer is used to generate the delays using Poisson distribution.

JSR223 Timer

The JSR223 timer is used to generate the delays using JSR223 scripting.

Assertions

Assertions in JMeter are the test plan elements that are used to validate the response received from server for a particular sampler request. In order to test a sampler response, we can add different assertions to the sampler requests as child. If an assertion fails, the sampler request is marked as failed and the same gets reflected in the test results listeners like - aggregate report listener.

Assertions are needed in performance test scripts to validate that the response received from server is correct and is not affected by increasing the load on the server.
The assertions are also helpful in doing functional testing of different kinds of applications by comparing the actual and expected output.

How to add an Assertion-

step 1:Right Click on a Sampler Request

step 2: Add Assertion and Click on the required Assertion

you can see the same in the screenshot.

                  The types of assertions in jmeter are response assertion,duration assertion,size assertion,HTML assertion,XML assertion ,compare assertion ,JSR223 assertion etc.

Response Assertion

The response assertion used in test scripts to validate a pattern in the response body, header, code, message etc. There are different pattern matching rules to validate the response like-

1. Contains - If the response text contains the regular expression to be matched
2. Matches - If the whole response text matches the regular expression
3. Equals - If the whole response text matches the pattern(not regular expression but the pattern string)
4. Substring - If the response text contains the pattern(not regular expression)
5. Not - To check that the pattern is not present in the response text

HTML Assertion

The HTML assertion is used to check the HTML syntax of the response.

Size Assertion

The size assertion is used to validate the size of the response with a specified value in bytes.

Compare Assertion

The Compare Assertion is used to compare sampler results.

BSF Assertion

The BSF Assertion is used to validate the sampler result using BSF scripting.

Duration Assertion

The duration assertion is used to validate that the sampler request gets processed within a specified amount of time.

XML Assertion

The XML assertion is used to validate that the response follows a valid XML syntax.

XML Schema Assertion

The XML Schema Assertion is used to validate the response against a specified XML schema.

XPath Assertion

The XPath assertion is used to validate the response using XPath expressions.

MD5Hex Assertion

The MD5Hex Assertion is used to validate the sampler result by checking its MD5Hex hashcode against a hashcode value provided.

SMIME Assertion

The SMIME Assertion is used to validate the body of a MIME message.

JSR223 Assertion

The JSR223 Assertion is used to validate the sampler result using JSR223 scripting.

Config elements

Config elements are used to configure or modify the sampler requests made to the server. These elements are added at the same or higher level of the samplers that we want to configure.

How to add an Config elements-

step 1:Right Click on either of Test Plan/Thread Group/Logic Controller

step 2:Hover over Add choose Config Element and Click on the required Config Element

for reference you can see the following screenshot.

               The config elements are counter,csv data set config,FTP request default,HTTP header manager ,HTTP cookie manager,Login config element,random variable,user defined variable,HTTP header request defaults , JDBC request defaults etc.

CSV Data Set Config

The CSV Data Set Config is used to read data from CSV file, put the data into variable(s) and then use the variable(s) in the sampler requests.

HTTP Cache Manager

The HTTP Cache manager is used in test scripts to add the Caching functionalities of web applications. This element is just required to be added at same level or higher than the sampler request where caching functionality is required.

HTTP Cookie Manager

The HTTP Cookie manager is required to for session handling by providing functionality of storing and sending of cookies.

User Defined Variables

As the name suggests, the User Defined Variable config element is used to create variables with a value (key-value pairs) that are used across the test script.

Random Variable

The random variable config element is used to generate random numeric values within a range of specified minimum and maximum values.

Counter

The counter config element is used to create a variable that gets incremented by a specified value in each iteration within a range of minimum and maximum values.

JDBC Connection Configuration

JDBC Connection Configuration is used with JDBC request sampler to create JDBC connection settings.

FTP Request Defaults

The FTP request defaults are used to create default settings while testing FTP servers.

DNS Cache Manager

The DNS Cache Manager is used while testing applications behind the load-balancers.

HTTP Authorization Manager

The HTTP Authorization Manager is used for testing applications requiring multiple logins for ensuring authorization.

HTTP Request Defaults

The HTTP Request Defaults config element is used for setting default values for HTTP requests.

HTTP Header Manager

The HTTP Header Manager is used to override the HTTP request headers.

Java Request Defaults

The Java request defaults config elements is used to specify default values for Java Request sampler.

Keystore Configuration

The Keystore Configuration config element is used to configure the loading of keystores.

Login Config Element

The logic Config element is used to create default credentials for the samplers using username and password in their setup

LDAP Request Defaults

The LDAP request defaults are used to create default settings while testing LDAP servers.

LDAP Extended Request Defaults

The LDAP extended request defaults are used to create default settings for LDAP Extended Request samplers.

TCP Sampler Config

The TCP Sampler Config is used for creating default settings for TCP Sampler.

Simple Config Element

The simple config element is used to create key-value pairs that can be used across the test script.

Pre Processor elements

The Pre Processor elements are used to modify the sampler requests before their processing(hence the name pre-processor).

How to add a Pre Processors in JMeter-

step 1:Right Click on either of Thread Group/Logic Controller

step 2: Add -> Hover Over 'Pre Processors' and Click on the required Pre Processor Element

you can refer the same in the following screenshot.

                    The pre processors in jmeter are beanshell pre processor , BSF preprocessor ,HTML link parser ,JDBC preprocessor , Regex user parameters , sample timed out and user parameters.

BeanShell PreProcessor

The BeanShell preprocessor is used to perform some operation using beanshell scripting before a sampler request.

HTML Link Parser

The HTML Link Parser is used to extract links from HTML response fetched from server.

HTTP URL Re-writing Modifier The HTTP URL Re-writing modifier can be added at either Thread Group level or Sampler level to fetch a specific sessionID parameter from the response of a request and then use the parameter's value on other requests.

JSR223 PreProcessor

The JSR223 preprocessor is used to perform some operation using JSR223 scripting before a sampler request.

JDBC PreProcessor

The JDBC PreProcessor is used to execute certain specified SQL queries before a sampler request processing.

RegEx User Parameters

The RegEx user parameters are used to extract HTTP parameters from certain request using a regular expression and then passed as request parameter to other sampler requests.

User Parameters

The User parameters are used to specify values for User variables used within Thread Groups.

Post Processors :

The Post Processors are the test plan elements that are used to perform certain actions after the processing of a sampler request. These post processors are usually used for extracting certain values from the response of a sampler request e.g. we can extract the value of session variables from an HTTP request and pass the session variable's value to the subsequent requests.

How to add a Post Processor in JMeter-

step 1:Right Click on either of Thread Group/Logic Controller

step 2:Hover over 'Add' select 'Post Processors'

step 3:Click on the required Post Processor Element

You can see the same in the following screenshot.

             The post processors in jmeter are beanshell ,BSF,CSS/Jquery .Debug,JDBC,JSON path,Regular expression and Xpath extractor.

Regular Expression Extractor

Regular Expression Extractor is the most frequently used post-processor. It is used to extract values from HTTP response using regular expression and to store the values to a variable. Then the variable can either be used as request parameter to other samplers or can be used for other purposes like assertions, debugging, storing in file etc.

BeanShell PostProcessor

The BeanShell PostProcessor is used to perform some operation using beanshell scripting after a sampler request processing.

CSS/JQuery Extractor

The CSS/JQuery Extractor is used to extract values from HTTP response using CSS or JQuery expressions and then the extracted value is stored in a variable.

XPath Extractor

The XPath Extractor is used to extract values from HTTP response using CSS or JQuery expressions and then the extracted vlaue is stored in a variable

Debug PostProcessor

The Debug PostProcessor is used to create a subSample having properties of previous sampler request, JMeter properties, JMeter variables or system properties.

JSR223 PostProcessor

The JSR223 PostProcessor is used to perform some operation using JSR223 scripting after a sampler request processing.

JDBC PostProcessor

The JDBC PostProcessor is used to execute certain specified SQL queries after a sampler request processing.

JSON Path PostProcessor

The JDBC PostProcessor is used to extract data from JSON response using JSON-Path syntax.

Result Status Action Handler

The Result Status Action Handler is used to stop a thread group or the whole test in case of a specific sampler failure.

Parameterization

Parameterization is the technique using which we can execute a test plan multiple times with different set of data. This helps in creating load test script that closely simulated real-world scenarios where different users use different test data.

Suppose, we have to do load test of a search engine like google. First step will be to record the search scenario. Now to do effective load test, we can't just playback the script for say 500 users. We should simulate 500 users that search for 500 different things. For this we can use parameterization, wherein we can have a CSV file that contains 500 different search keywords. Now instead of the static search item that we had recorded in our script, we can include the search items from the CSV file dynamically.

In jmeter, one of the common ways to parametrize your performance scripts is to use a CSV file. The best example of CSV input files usage is a login process. If you want to test your application across different users, you need to provide a list of user credentials.

Let’s assume that we have a login request that works for one specific user:

The following screenshots guide you to how to do parameterizatio

Step 1: open jmeter

step 2: add thread group

step 3: add HTTP sampler

step 4: enter all details as shown in the screenshot like ip address ,port ,method and path and also peaste the body of the request.

step 5: Now instead of email and pass we need to pass the parameters.

To achieve this we have to go for parameterization.

To pass any variable we have to use this format ---------- ${parameter name}

so here instead of name we enter ---------${email}

instead of pass we enetr ----------${password}

screen shot : 1

screenshot 2:

                  To pass the parameters we are using csv data config element .As shown in above screen shot add csv data congig element to thread group.

Configeration elements in csv data config element:

step 1 :First prepare the valid test data i.e. email and passwords and save those in a file with the extension of a file as “.csv” .Now browse that file path .

Step 2: leave the file encoding as it is.

Step 3: we have to enter variable names as like as how we enetere the column names in csv file (email , password) with comma or space or tab separated

step 4: hit on the drop down and choose whether we wanna ignore first line or not.

If we wanna ignore first line -----------choose TRUE if not choose FALSE.

Step 5 : choose delimeter either we used the delimeter as space/ camma/tab

step 6: If you wanna allow quoted data is choose TRUE if not choose FALSE

step 7: If you wanna recycle the data then choose TRUE if not FALSE

step 8: choose the EOF as FALSE if you choosen the above as TRUE if not choose FALSE

step 9: sharing mode will be all threads means ---- All the threads will share the data from csv file

If you choose current thread----- Apply only for perticulat thread only.

Note: To know whether the data is passing as parametere or not we can check by adding listner.

Step 1: Add the listner (view result tree)

step 2: run the test

step 3: Hit on the view result tree

step 4: hit on request.

Now as shown in the below screenshot the parametrs are passed instead of email and password.

Correlation

Correlation is the most important aspect of scripting. It usually includes fetching dynamic data from preceding requests/calls and posting it to the subsequent requests.

Let's take an example to find out why exactly we need correlation. Suppose we have recorded a scenario in which-

User enters login details and click OK button

Home page opens and user take further actions

Now, if we just playback this script, the test will fail even for a single user. This is because of the authentication mechanism used. When we login to a website, session variables are dynamically created. These session variables are passed to the subsequent requests and help validation & authentication of the actions performed. So, one cannot just record and playback the requests having these variables. Here, we need to correlate the web requests with the dynamic variables. And for correlation, we need to use the "Regular Expression Extractor" which makes use of regular expressions. So, before going deep into Correlation, let's first understand "Regular Expressions".

Regular expression

Regular expressions are used to fetch data from a string based on a search pattern. Basically, in order to extract any value (generally a dynamically created value) from a string response, we define a left bound of the variable then some wildcard characters and then a right bound-

(leftbounday) (body to be capture) (right bounday)

For example : The server is returning the session id for login request . we wanna capture that session id .For that we have to use regexpression extractor

server returing value is

session id =”1e234323254343464”/>?

Left boundary = session id=”

body to capture = 1e234323254343464

right boundary = ”/>?

The regurar expression is ---------- session id =”(.+?)” />?

If we use the above expression every reply the expression will extyract the server return value.

Where

“. “- match any character

“+” - one or more times

“? “- stop when first match succeeds

Steps to follow to capture dynamic value:

step 1: open jmeter

step 2: Add thread group

step 3: add sampler

step 4: Add regular expression extractor

From the following screen shot you can find more details.

Configeration elements in regular expression:

Name : you can give any meaning ful name as a name.

Name of created value : give any meaning full name but to use extracted / dynamic value some where at that time we have to use same name as a parameter.

Regular expression: here we have to peaste the regular expression which is formed by you.

Templet: here enter the posion of occurence of the dynamic value (ex : if it is first occurance then give like $1$)

Match no : If you wanna pick random number then give 0 if not leave blank.

Data Base Tesing (JDBC Request)

Using JDBC request sampler we can test the database.

Steps to do the database testing.

Step 1: open jmeter

step 2: add thread group to test plan

step 3 : Add the config element (JDBC connection cofig)

( see the following screenshot for reference.)

 The Config Element- "JDBC Connection Configuration" is required to be added as child of the Thread Group. The properties in "Connection Pool Configuration" and "Connection Validation by Pool" can be kept with default values. Appropriate values for the following parameters need to be configured in "Database Connection Configuration" section-

1. Database URL - The URL of the database server
2. JDBC Driver class - The database driver name e.g. com.mysql.jdbc.Driver
3. Username - The username of the user having access to run the SQL query in the database
4. Password - The password of the user having access to run the SQL query in the database

step 4: Add JDBC request sampler.

(see the following screenshot)

The Sampler- JDBC Request needs to be added as child of the Thread Group below the JDBC Connection Configuration. Here we can select the type of SQL query form the "Query Type" drop-down and place the SQL query in the "Query" text field.

Step 5: Add the listeners . ( To know the output we have to add the listeners.)

Step 6: add assertion also if you want. (For validation)

step 7: Run the test.

FTP request sampler

The following steps we have to follow to test the FTP server.

Step 1: open jmeter

step 2: add thread group to test plan

step 3: add config element as FTP request defaults. ( see the following screen shot)

we have to enter configuration details .

The Config Element- "FTP Request Defaults" is required to be added as child of the Thread Group. Here you can add configure default properties that can be used by multiple "FTP Request sampler" like FTP server name, port, remote file, local file, mode etc.

Step 4: Add the sampler FTP request (see the below screenshot)

            Enter all the configuration elements as like as FTP request config element but additionally we have to enter credentials ( user name and password) to connect to the FTP server.

Step 5: Add the listeners . ( To know the output we have to add the listeners.)

Step 6: add assertion also if you want. (For validation)

step 7: Run the test.

Distributed load testing:

Distributed load testing is the process using which multiple systems are used for simulating load of large number of users. In JMeter, this is achieved by creating a Master-Slave configuration.

The reason of using more than one system for load testing is the limitation of single system to generate large number of threads (users).

For distributed load testing we need to create Master-slave configuration wherein

Before we start,there are a couple of things to check.

• the firewalls on the systems are turned off.
• all the clients are on the same subnet.
• the server is in the same subnet, if 127.0.0.1 ip addresses are used. If the server
• Make sure JMeter can access the server.
• Make sure you use the same version of JMeter on all the systems. Mixing versions may not work
• correctly.

Once you've made sure the systems are ready, it's time to setup remote testing. The tutorial assumes you already have JMeter installed on all the systems. The way JMeter works is 1 master controller initiates the test on multiple slave systems.

Terminology

Before we dive into the step-by-step instructions, it's a good idea to define the terms and make sure

the definition is clear.

Master – the system running Jmeter GUI, which controls the test

Slave – the system running jmeter-server, which takes commands from the GUI and send requests to the target system(s)

Target – the webserver we plan to stress test

Master will control all the slaves and collect the test results.

To make the system work firewall needs to be turned off and all the systems need to be in same subnet. Also, preferably all the systems need to use same version of JMeter and Java.

1. First of all we need to start the jmeter-server.bat in the slave systems. For this just go to the bin folder inside JMeter home directory and run the batch file jmeter-server.bat(for windows) or jmeter-server (for linux).
2. Now on the master system open the properties file jmeter.properties and edit the remote_hosts entry. Remove the loopback address's value (127.0.0.1) for the remote_host entry and specify the IP addresses of all the slave systems separated by commas.

In the following screen shot you can see initially only one url is there.

Now i am adding two more hosts under remote hosts and configeration . You can see the same in the below screenshot

Like this you can add the hosts as many you want.

Starting the Test

At this point, you are ready to start load testing. If you want to double check the slave systems are working, open jmeter.log in notepad. You should see the following in the log.

Jmeter.engine.RemoteJMeterEngineImpl: Starting backing engine

If you do not see this message, it means jmeter-server did not start correctly. For tips on debugging the issue, go to the tips section. There are two ways to initiate the test: a single system and all systems.

How to Start a single server   

step1. click Run at the top

step2. select Remote start

step3. select the IP address

(see the screenshot )

How to start all servers

 step1. click Run at the top

step2. select Remote start all or use CRTL-Z (see the screenshot)

Saving the test plan

You can save an entire Test Plan either by using Save or "Save Test Plan As ..." from the File menu. Or by default save button will be there in jmeter hit on that save the script by providing a name .jmx.

Running a test plan

You can run your Test Plan choosing Start (Control + r) from the Run menu item. When JMeter is running, it shows a small green box at the right hand end of the section just under the menu bar.

The numbers to the left of the green box are the number of active threads / total number of threads. These only apply to a locally run test; they do not include any threads started on remote systems when using client-server mode .

In the following screenshot you can see the save and run buttons.

Recording Script with Jmeter

we can record the script using the jmeter non-test element( Http test script recorder)

Step 1: open jmeter

step 2: add to non test element (HTTp test script recorder)

step 3:Now in http test script window,port value will be 8080 by default,otherwise set it to 8080

step 4:In the drop down list,select recording controller as the target controller.

In the next step,add recording controller,under http test script recorder.Recording controller enables to record script under it,so that it will be in a structured way.

Step 5 :The workbench is now ready to record scripts.Now open web browser and go to settings.

Step 6:In settings,go to proxy server and check the check box.

Step 7:Type localhost in the address text box and in the port provide the port number which we have given to proxy server port ie 8080.

step 8:Finally click ok button and close the window.

Step 9:To start recording the script, type url of the application in the browser and press enter. Now in recording controller under workbench,some http request will be recorded. For eg, if the static web site has five pages and if we want to record those five pages in different group or specified name,then it can be done.

Step 10:In the next step, add simple controller to the http test script recorder and select the entire http request from the recording controller and paste it under simple controller.

Step 11:Once the recording is done,go to internet options and uncheck the check box in proxy server and save it.

Step 12:In the next step,copy the script to test plan under thread group.

Step 13:Finally, add listeners to the thread group.Add agrregate grph,view results tree and response time graph to view the results.

Note: see the following screenshot for reference

Execution order of Test Elements

Following is the execution order of the test plan elements:

1. Configuration elements

2. Pre-Processors

3. Timers

4. Sampler

5. Post-Processors (unless SampleResult is null)

6. Assertions (unless SampleResult is null)

7. Listeners (unless SampleResult is null)

How to generate report(HTML format)

GUI mode:

once test got completed the results will be stored in a .jtl extension file.

Step 1: Navigate to tools and choose generate HTML report (see the following screenshot)

step 2: browse the result file (jtl file)

step 3:browse the user.properties file

step 4: give the path where to generate the html formated file.

Step 5: hit on generate report

step 6: Navigate to given output directory for HTML format report file.

Non-GUI mode

Once the test was executed in non-gui mode the jtl file will be saved in the given directory. After the execution follow the below steps to generate HTML report in non-gui mode.

Step 1: open the terminal/ command propt

Step 2: Enter command

for example :

I written the following command to generate the report in non-gui mode.

/home/madhureddy/Desktop/apache-jmeter-5.1.1/bin/jmeter -J jmeter.save.saveservice.timestamp_format="yyyy/MM/dd HH:mm:ss" -g/home/madhureddy/Desktop/Chatak_AFCS_23_MAY_Duration_15min_100TC_60R_1.jtl -o /home/madhureddy/Desktop/Chatak_AFCS_23_MAY_Duration_15min_100TC_30R_1

Explanation for the above example how i written the command:

Analysis

After executing a load test, we need to interpret the test results. For result interpretation, we use Listeners in JMeter. These listeners provide different matrices about the load test. In this post, we will see the most commonly used matrices, their meanings and the how they are calculated internally from raw data.

Result matrices by Aggregate Report Listener-

Label- Label is the name of the sample or the Transaction Controller

Samples - The total number of samples corresponding to a given sample

Average - The average time taken (in milliseconds) to execute the requests under a given label. So, if there are 10 samples getting executed then average time taken will be-

Average = Total time taken by all samples /#samples

Median - The median is basically the middle value of response time in the sorted list of samples

90% Line - The Apache JMeter manual describes 90% line as- "90% of the samples took no more than this time". It is actually the 90 percentile of the response times of the samples -

90 percentile = (90/100)*N+1/2 where N is the number of samples

So, if there are 10 samples then 90%line will be 9.5 or 9. It means the 9th value in the sorted list of samples (sorted according to ascending order of their response times) will be the 90% line value.

Min - The minimum time (in milliseconds) taken by the sample

Max - The maximum time (in milliseconds) taken by the sample

Error % - Percentage of errors in the samples

Throughput - Throughput as we all know is output per unit time. In JMeter terms we define throughput as the amount of load applied on the server. So, numerically-

Throughput = Total number of requests to the server/ Total time

or Total number of requests to the server/(End time of last sample -Start time of first sample)

Here we just defined Total time in which load was applied on the server as time duration between Start of first sample and end of last sample.

KB/sec - The metric KB/sec is nothing but the throughput measured in terms of bytes. So,

KB/sec = (Throughput*Average bytes) /1024

Here Average bytes is the average value of the sample response in bytes and the term 1024 is used to convert the value (Throughput*Average bytes) into kilobytes.