In Jmeter

zip into the JMeter 2. How to use "loop controller" in jmeter with example As you know, Apache jmeter has many logic controllers and loop controller is one of the mostly used controller in performance testing of software web application using jmeter. JMeter is open source software for performance testing. Next, we just need to add this folder to the path environment variable so that it's accessible from the command line. A JMeter tab opens in the Output window after the script has been loaded. Compare Apache JMeter vs Testim. 11 à bin à jmeter-server. Apply to 1257 Jmeter Jobs on Naukri. User interface. In this article, we'll go through the basic usage of CSS Selectors in JMeter scripts. I had the same issue. , and it requires JDK 5 or higher. Explore Jmeter Openings in your desired locations Now!. JMeter is my favorite & one of the best tools I have ever used. Since JMeter 2. LET'S GET STARTED. In this blog, I would like to discuss one of the features of JMeter which allows you to do parameterization using the CSV file where if you have to execute one test plan for more than one user at the same time, you can do so using the CSV data set config. /bin/jmeter on command prompt(for Unix) or Run bin/jmeter. Except, our script still won't work because there's those other 10 dynamic variables we need to correlate as well. Basically, the [email protected] set contains two types of plugins. jmeter -H my. JMeter training in noida is designed according to current IT market. I ve already set up a. The above shows the concept of distributed load testing whereby you initiate your test from a central node (called the Jmeter master) which in turn sends the test script to the slaves, the slaves are the nodes/pods that carries out the load testing. JMeter Exception: java. log is located under the bin directory (or using -j option to specify it). Remote Testing: In the event that your JMeter client machine is unable, performance-wise, to simulate enough users to stress your server, an option exists to control multiple, remote JMeter engines from a single JMeter GUI client. If there are many users, too many threads may get created and start affecting the response times adversely due to bandwidth contention at the JMeter side. If you don’t know what JMeter is, this is the first question you should do. The same recorded number is displayed when i run the script. In JMeter, simply insert a JSON Path Extractor from the Post-Processors menu and enter variable name, JSONPath expression and default value: JSONPath expressions are short and easy to read, improving considerably the maintainability of the test script. hi, I am facing an issue in Jmeter. The different part or component of JMeter is called Element which co-relates with each other but designed for different-different purpose. Invoke the jmeter-server. org For additional commands, e-mail: [email protected] I'd like to think that by using assertions with a custom JUnit listener JMeter could be run in as part of functional testing. jmeter – performance of cpu and memory usage using perfmon plugin Posted on January 23, 2015 by Knowledge World For You Open the Jmeter Application by clicking Jmeter. A Jmeter Test Plan must have listener to showcase the result of performance test execution. Are you using Apache JMeter for your test? Please confirm so that I will share workload model for given scenario. jmx -l result. sh file from the…. We will show you how to use the graphical user interface to build a test plan and run tests against a web server. Note: To use the Web services samples you also need the mail. JMeter Tutorials, JMeter is an open source application and is a pure Java application designed for load testing and functional testing of software. Reporting feature in JMeter. Apache JMeter is open source software, a 100% pure Java desktop application designed to load test functional behavior and measure performance. Lifetime Updates. One way to manage this is to set up multiple Eclipse workspaces -- one for JMeter, and one (or more) for other projects. Learn Jmeter in 1 Day: Definitive Guide to Learn Jmeter for Beginners [Krishna Rungta] on Amazon. It is also the core technology in countless other browser automation tools, APIs and frameworks. Invoke the jmeter-server. The Apache JMeter™ desktop application is open source software, a 100% pure Java application designed to load test functional behavior and measure performance. Configuring JMeter. So i installed a lower version and recreated the. On Linux/Unix, JMeter can be invoked by clicking on JMeter shell script. If you work on other projects in addition to JMeter, you probably don't want the JMeter formatting to apply to your other projects. It is a platform-independent tool. JMeter is the best open source load testing tool to measure the performance of an application. JMeter is my favorite & one of the best tools I have ever used. Regular Expression Extractor, convert it into a JMeter Variable and add it as a parameter to the next request. Note: To use the Web services samples you also need the mail. It is also the core technology in countless other browser automation tools, APIs and frameworks. How to run a JMeter test in Jenkins. We will learn the basics in a very easy way and you will be able to use JMeter for all types of performance and functional testing. properties file is used to define additional JMeter properties. I'm Beginner in Jmeter. # Optional list of JMeter variable names whose values are to be saved in the result data files. com Port 80. If you don't know what JMeter is, this is the first question you should do. JMeter 설정및 사용법 made by 정문철 reviewed by 손영수 Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. JMeter is a great load testing tool which provides many features to create a realistic load test script. Within a test plan you can have Thread Groups, controllers, listeners, timers, assertions, and other elements. A Jmeter Test Plan must have listener to showcase the result of performance test execution. Total Calculation in JMeter When calculating total row values for jmeter we should not consider labels. But the jmeter window is not showing the workbench section in the left. Performance testers call this process correlation. Are you using Apache JMeter for your test? Please confirm so that I will share workload model for given scenario. Apache JMeter is open source software, a 100% pure Java desktop application, designed to load test functional behavior and measure performance of web sites. In our last couple of post in JMeter Test Plan creation, we created HTTP Requests manually by adding them one by one (which we need to test). org, various third-party plugins and even core JMeter plugins. Even it is an unrealistic scenario. Jmeter does not report the results automatically after the completion of the test like other Load Test tools. Disclaimer: This blog is related to performance testing approach, performance testing tools, and their functioning. Using a performance scripts recorder is a great way to avoid routine tasks and still get the best test scripts. It is a platform-independent tool. I created a WebSocketHandler. Before installing JMeter, make sure you have JDK 1. Running Performance Tests part of CI/CD is now a days essential. The View Results in a Tree shows the results of test plan in tree structure. How RedLine13 Enhances JMeter Load Testing. This article complements the JMeter User's Manual and provides guidelines for using some of the JMeter modeling elements to develop a quality test script. AJAX- JSON hasn't any special requirements with respect to Jmeter as Jmeter only cares about request/response so as long as the order of requests (and the dynamic data) is the same , it should work. and Googling it didn’t turn up anything. One of the most interesting features of JMeter is to create realistically & accurately simulates the scenario which mimics the real world use. Apache JMeter 3. Apache JMeter is one of the best open source load testing tools available in market. properties in which we can mention our file path to be read to use it in JMeter. As you can see, there is not problem with JMeter with memory size and CPU, but what calls my attention is the Network IO. If you don’t know what JMeter is, this is the first question you should do. It was originally designed for testing Web Applications but has since expanded to other test functions. As an open source tool it is popular to many web load and performance tester. Configuring JMeter. HPE Unified Functional Testing provides two views—and ways to modify—a test script: Keyword View and Expert View. properties) you will have to find the following settings and adjust them to your needs. A common problem in JMeter is that you want a CSV file as an input and want to execute each line, then continue. How to run Jmeter tests in non-GUI mode, automated with a shell script Apache Jmeter is a great versatile tool for performance testing of web servers, DBMS servers etc. As Jmeter is a java application , it runs on top of it. Apache JMeter is an excellent testing tool that provides an insight on how applications might behave under load, allowing organizations to focus on making adequate preparations for the delivery of quality, robust, and foolproof applications to stakeholders. I've a recording case using browser proxy in oracle apex , Then I run this case on Jmeter. jar and activation. JMeter is a great tool, but it has its own limitations. Set JMeter as a proxy and record your log-in flow ( Click here for a video tuorial ). Jmeter is configured to create 10 users (threads), Ramp-up in 1 second and repeat that for 3000 times (the idea in this test is to get to know the limits of the server, how many req/sec can handle). Under Global Settings section, you can see Port field. By the end of this series of articles and video tutorials, you would be able to understand the basic concepts of JMeter, how to send requests and modulate load factor, how to use assertions to validate responses from the server and real time example. Total Calculation in JMeter When calculating total row values for jmeter we should not consider labels. One way to manage this is to set up multiple Eclipse workspaces -- one for JMeter, and one (or more) for other projects. BindException: Address already in use: connect By admin on Jul 28, 2008 in open source This is the exception I encountered whenever I run load test against HTTP or Web Service Requests using JMeter. Main purpose of this tool is to do load test function behavior and measure performance. Threads corresponds to number of users. It doesn't exist currently, though there is an Ant task for JMeter that you might find useful. Running a JMeter test in Jenkins isn't very complex. To analyze it, you need to extract data from a web page and create a new HTTP request with the retrieved value. Below are some of the protocols supported by JMeter:. Next, we just need to add this folder to the path environment variable so that it's accessible from the command line. Take a good look over the opened element in JMeter window. JMeter will use this to calculate the End Time, and ignore the End Time value. In latest JMeter 3. It doesn't exist currently, though there is an Ant task for JMeter that you might find useful. Some browsers ignore proxy settings for localhost or 127. This was written while using JMeter versions 2. In this article we examine debugging options in JMeter. Am new to Jmeter and I ran the test successfully. Apache JMeter Download. A single JMeter instance might not be able to generate enough load to stress test your application. It was originally designed for testing Web Applications but has since expanded to other test functions. For comprehensive list, check out JMeter's official documentation. 0 version apache software included Generate Jmeter Report Dashboard using APDEX(Application Performance Index). When starting a test, the only feedback that there's something happening is the thread count which is displayed in the top right hand corner (and maybe the sound of a creaking application somewhere). Apache JMeter is open source software, a 100% pure Java desktop application designed to load test functional behavior and measure performance. org ===== Disclaimer: This message and the. I have more than 100 Jmeter scripts and every script contains more then 10 action. You can even ramp up the requests to see how your app deals with changing load,. BlazeMeter Chrome extension enables you to - Record. With the JMeter proxy in place, you can create a test plan by simply visiting the web site you wish you test. *FREE* shipping on qualifying offers. IP Spoofing in Jmeter. As soon as you save the file …The Load Test Begins… Step10). Select Recording template on the list. Now we see that step by step how you can use it- Step 1: Need below software Apache JMeter - Download and run the. JMETER Apache JMeter is a 100% pure Java Desktop application designed to load-test functional behavior and measure performance. co/ADK2A8Pl14. I had the same issue. Thanks, Matt. com/playlist?list=PLhW3qG5bs-L-zox1h3eIL7CZh5zJmci4c JMeter Intermediate Playlist : https://www. How RedLine13 Enhances JMeter Load Testing. If you don’t know what JMeter is, this is the first question you should do. I’ve been documenting the process for designing performance and regression tests on BI 4. I successfully installed jmeter into my windows machine. How to Extract values from Response header in JMeter If we record any web application through Jmeter and replay it, most of the times it could fail. Apply to 1257 Jmeter Jobs on Naukri. For example, when testing an API, we could get a JSON response which could contain JSON Arrays. JMETER Apache JMeter is a 100% pure Java Desktop application designed to load-test functional behavior and measure performance. In this tutorial, we will go over how to use Apache JMeter to perform basic load and stress testing on your web application environment. Docker image for Apache JMeter. sh on Linux/Unix. 1 is the latest version available in the market as of now with some more enhancements lined up for future. Installation. JMeter respects proxy settings. Just remember that the test has to be run in from the command line. Set JMeter as a proxy and record your log-in flow ( Click here for a video tuorial ). Its sole task is to put a delay between requests. Jmeter is a popular open source performance testing tool. Apache JMeter 3. If your application is expecting some form of security token as request parameter or request header or cookie or whatever you will need to extract it from previous response using i. 4 or higher. I'd like to think that by using assertions with a custom JUnit listener JMeter could be run in as part of functional testing. The Apache JMeter™ desktop application is open source software, a 100% pure Java application designed to load test functional behavior and measure performance. It can be used to simulate a heavy load on a server, group of servers, network or object to test its strength or to analyze overall performance under different load types. They do not come with a standard JMeter installation but have to be installed separately. Explore Jmeter Openings in your desired locations Now!. This article was written due to the difficulty I initially found in creating a Java Sampler for JMeter. How to use HTTP Basic Authentication in JMeter From time to time you will need to test URLs, which can sometimes be restricted from anonymous visits. After this course you can work with JMeter for personal and enterprise projects. In the JMETER_HOME/bin folder, we have a jmeter. The current status of the load generator is also displayed in the Services window. But if you are running on a hosted environment, you might want to speak to your host about this first; you are potentially running a Denial of Service attack on your own setup. Apache JMeter is an open source performance tool which is helpful in testing load test for WebApplications and WebServices,REST API services. We had covered Load Testing Using Apache Jmeter in our previous post. Apache JMeter is an excellent testing tool that provides an insight on how applications might behave under load, allowing organizations to focus on making adequate preparations for the delivery of quality, robust, and foolproof applications to stakeholders. Samplers are the actual requests, JMeter sends to the web server under test. Hi, Does anyone know how to write custom code in java for Jmeter. This is important, because removing rarely used features like JDBC and LDAP will tidy up huge popup menus from unused items. The hardest part of using it is authoring the test cases (e. To deal with these challenges efficiently, you can use CSS Selectors in your JMeter. Jmeter does not report the results automatically after the completion of the test like other Load Test tools. In our last couple of post in JMeter Test Plan creation, we created HTTP Requests manually by adding them one by one (which we need to test). This is a JMeter window. JMeter provides a user interface. Let's download JMeter, unzip it, go to the bin folder and run the executable (*. Said otherwise, we need to install and trust JMeter's Root Certificate to allow JMeter's Proxy to decrypt HTTPS traffic. 0, it's far easier to extract data from Json responses using the Json variable extractor. JMeter is a great tool, but it has its own limitations. It was originally designed for testing Web Applications but has since expanded to other test functions. *FREE* shipping on qualifying offers. Apache JMeter is an open source software. Apache JMeter Download. Our JMeter Training in Bangalore is designed to enhance your skillset and successfully clear the JMeter Training certification exam. Course is designed in such a way that the user can start the things from the very scratch with out any prior knowledge on Jmeter or Performance Testing. 1 is the latest version available in the market as of now with some more enhancements lined up for future. bat file in your Jmeter>bin folder- 2. JMeter respects proxy settings. How to run Jmeter tests in non-GUI mode, automated with a shell script Apache Jmeter is a great versatile tool for performance testing of web servers, DBMS servers etc. JMeter Beginner Playlist : https://www. Correlation in Jmeter with Regular Expression Extractor Correlation is the most important aspect of scripting. Can some one tell me how to enable ssl in jmeter?. As you can see, there is not problem with JMeter with memory size and CPU, but what calls my attention is the Network IO. In this case we will debug “Regular Expression Extractor”. Where * indicate the your dir in windows. 3) How to parameterize the script and run from CLi mode: By using JMeter -Property function we can run the same script from CLI mode with different thread count and iterations w/o the need to open and modify the script every time before running the script. Note: To use the Web services samples you also need the mail. org, various third-party plugins and even core JMeter plugins. Basically, the [email protected] set contains two types of plugins. 0 version apache software included Generate Jmeter Report Dashboard using APDEX(Application Performance Index). It contains two sections − Test Plan −In this sesction where the real test plan is kept. ' You now have a test plan with some basics already configured. Even it is an unrealistic scenario. com/playlist?list=PLhW3qG5bs-L-zox1h3eIL7CZh5zJmci4c JMeter Intermediate Playlist : https://www. When we enable , following files are set to use for initialization. Or you just need to parse the response and validate an assertion. bat file in bin directory of jakarta-jmeter Directory, you will see the following JMeter Screen. bat script file needs some changes to run JMeter, described at the end of post). Jmeter is a cute tool for system administrators developed in Java that allows you to test the performance of different pieces of software and hardware: Java complements, servlets, Perl scrpts, databases or FTP servers. JMeter requires the following steps: 1. Listeners capture the response coming back from Server while Jmeter runs and showcase in the form of – tree, tables, graphs and log files. to make the available content more readable, knowledgeable and understandable to the layman. Or you just need to parse the response and validate an assertion. Mitigation: * Users must use last version of Java 8 or Java 9 * Users must upgrade to last JMeter 4. Select the Recording Template and press 'Create. ${__functionName(param1,param2 ,param3)}Note that if a parameter contains a ". , in the JMeter GUI). JMeter Beginner Playlist : https://www. By: Guy Salton, BlazeMeter Inc. In the JMeter properties file (jmeter. the problem was the version of the Jmeter on the remote server was 2. 7 for my load testing. bat Note: Do refer the following link for detailed information on configuring the load generators. Ex: We have a Scenario like Login into the Site doing some actions like booking the tickets and Sign-out from the site. Jmeter is configured to create 10 users (threads), Ramp-up in 1 second and repeat that for 3000 times (the idea in this test is to get to know the limits of the server, how many req/sec can handle). ----- To unsubscribe, e-mail: [email protected] This presentation explains about Beanshell scripting in Apache JMeter. In this blog, I would like to discuss one of the features of JMeter which allows you to do parameterization using the CSV file where if you have to execute one test plan for more than one user at the same time, you can do so using the CSV data set config. This element is called the “CSV Data Set Config”. You can set everything from the amount of simultaneous users of the service, to the amount of requests they make a second. Official Twitter account of JMeter, the open source load testing tool by @TheAsf. To write the blog I have referred Performance Testing tools official site like Micro Focus LoadRunner, Apache JMeter etc. JMeter is my favorite & one of the best tools I have ever used. properties) you will have to find the following settings and adjust them to your needs. Explore Jmeter Openings in your desired locations Now!. To analyze it, you need to extract data from a web page and create a new HTTP request with the retrieved value. Live JMeter Online Training 30 hours 100% Satisfaction Guaranteed Trusted Professionals Flexible Timings Real Time Projects JMeter Certification Guidance Group Discounts JMeter Training Videos in Hyderabad, Bangalore, New York, Chicago, Dallas, Houston 24* 7 Support. In this tutorial, we will go over how to use Apache JMeter to perform basic load and stress testing on your web application environment. When starting a test, the only feedback that there's something happening is the thread count which is displayed in the top right hand corner (and maybe the sound of a creaking application somewhere). log is located under the bin directory (or using -j option to specify it). How to run Jmeter tests in non-GUI mode, automated with a shell script Apache Jmeter is a great versatile tool for performance testing of web servers, DBMS servers etc. JMeter is a bit light on user feedback from actions performed in the graphical interface. Where * indicate the your dir in windows. JMeter tests are built around the idea of a test plan. list in FireFox Browser, but when i try to record request using HTTP Please double check, the JMeter Proxy certificate must be in the Authorities tab in Certificate Manager in Firefox. Before installing JMeter, make sure you have JDK 1. I've a recording case using browser proxy in oracle apex , Then I run this case on Jmeter. Configuring the JMeter How to configure recording settings in JMeter? To access the applications behind the proxy, you need to launch JMeter behind proxy. JMeter was developed by Apache Software Foundation, Jakarta, or Apache JMeter for short. Apache JMeter may be used to test performance both on static and dynamic resources, Web dynamic applications. So, Let’s move ahead with our “JMeter Tutorial” to know more about the particular testing tool. Apache JMeter Download. A jmeter proxy test complete Test Plan is generated In the HTTP Request Defaults element: Server name or IP enter m Path leave blank. Whenever we make changes to the code its important ensure our code changes doesn't affect performance. pdf), Text File (. JMeter can be used as a unit-test tool for JDBC database connections, FTP, LDAP, Webservices, JMS, HTTP, generic TCP connections and OS native processes. 0 version Besides, we remind users that in distributed mode, JMeter makes an Architectural assumption that it is operating on a 'safe' network. JMeter is amazing tool, but it still has some drawbacks. Or you just need to parse the response and validate an assertion. We start training our students from, “What is JMeter?” and “Why JMeter?”. Free Guide to JMeter Tutorial. The GUI mode of JMeter is perfect for adding and editing new configuration elements, thread groups, and samplers as a result of which you can view a number of different listeners helping for. Now we have moved to HTTPS. The JMeter load test feature allows you to generate a high load on a server and determine its capacity and limitations. JMeter Beginner Tutorial 2 - How to create first Jmeter Test Automation Step by Step - Raghav Pal. As this site shows, one JMeter instance will be able to control many other remote JMeter instances and generate larger load on your application. Running a JMeter test in Jenkins isn't very complex. Running The Docker image will accept the same parameters as jmeter itself, assuming you run JMeter non-GUI with -n. Samplers are the actual requests, JMeter sends to the web server under test. TestLeaf is a market leading training company at Chennai, which provides a comprehensive suite of training services including RPA, Data Science, Python, Selenium, Appium, Cucumber, Loadrunner, Jmeter, UFT and so on. Now I'd like to understand what the results mean and what is classed as good/bad measurements, and what can be suggested to improve the results. Can some one tell me how to enable ssl in jmeter?. Apache JMeter is mainly used to test the performance and stability of an applicat. 100% Safe & Secure Access. I opened "jmeter. As an open source tool it is popular to many web load and performance tester. bat (or preferably setenv. JMeter can conduct load and performance test for many different server types − Web - HTTP, HTTPS, SOAP, Database via JDBC, LDAP, JMS, Mail - POP3, etc. JMeter Training is an ever-changing field which has numerous job opportunities and excellent career scope. I'm Beginner in Jmeter. Listeners facilitates viewers to view responses generated by samplers in the form of tables, graphs, trees or simple text in some log files and also give pictorial access to the data collected by JMeter about those test cases as a Sampler component of JMeter is executed. Built-in Functions in JMeter What are built-in functions in JMeter? Built-in functions are functions provided by JMeter that allows you access JMeter/JVM properties, manipulate data, and run scripts. In the HTTP Request Defaults element: Return to HTTP (S). If you are a beginner, then the below given information might be useful to you. , in the JMeter GUI). Complete Understanding of Correlation in JMeter Aggregate Report in Jmeter is one of the most essential listener. How to use HTTP Basic Authentication in JMeter From time to time you will need to test URLs, which can sometimes be restricted from anonymous visits. If you're one of them, you may want to load test. If 10 threads are used, and the ramp-up period is 100 seconds, then JMeter will take 100 seconds to get all 10 threads up and running. So from a script perspective that would look something like this: Thread Group |-For Each CSV Line | |-HTTP Request (CSV input) |-Do something else. Before installing JMeter, make sure you have JDK 1. Showing 1-20 of 1929 topics. Compare Apache JMeter vs Testim. Iterating over a CSV file in JMeter. With RedLine13, you can run a JMeter Load Test with your JMX script of any mobile application, web application, or API in 10 minutes. Jmeter is a cute tool for system administrators developed in Java that allows you to test the performance of different pieces of software and hardware: Java complements, servlets, Perl scrpts, databases or FTP servers. These elements are added at the same or higher level of the samplers that we want to configure. What is JMeter? Apache JMeter is a testing tool used for analyzing and measuring the performance of different software services and products. sh for Linux/Unix). This book is a great starting point to learn about JMeter. To download JMeter simply go to official Apache JMeter website and download the zip or tgz package. It is written in Java and works as a desktop application. New book on Apache JMeter by 3 developers of the JMeter project: Philippe M. I created a WebSocketHandler. It was originally designed for testing Web Applications but has since expanded to other test functions. However, one has to wait until the end of the test to view the results. We already found some documentation and followed it to configure the Port, the Host, API TOKEN etc Now we wanna test if the configuration is correct and Jmeter is communicating well with our Dynatrace. The types and resources can vary be it corporate libraries, knowledge bases, targeted forums, or other. Hello All, In this blog, we will see how we can generate the report for our load testing. bat file in bin directory of jakarta-jmeter Directory, you will see the following JMeter Screen. Apache JMeter is an open source testing tool. Hi, I am new in jmeter. Why You Need Taurus for JMeter Scripts. It's a pure Java application where you can use even your own Java code to customize and randomize your tests. If you don’t know what JMeter is, this is the first question you should do. What is JMeter? Apache JMeter is an open source load testing application which is purely developed in Java. Trust me, there is no risk unless you leak the Root certificate to a malicious third party. This is important, because removing rarely used features like JDBC and LDAP will tidy up huge popup menus from unused items. For example, when testing an API, we could get a JSON response which could contain JSON Arrays. Set JMeter as a proxy and record your log-in flow ( Click here for a video tuorial ). In this article, we will see one such very important feature. In this JMeter Tutorial, we explain how to send one or multiple JSON files in the body of the HTTP request. In that case, JMeter could overwhelm your test server by making too many requests in a short amount of times. As Jmeter is a java application , it runs on top of it. So whenever you need to change a parameter like thread number, base url, etc. More JMeter tips: Running your first load test with JMeter JMeter is a highly recommended tool for load testing open source Java applications, as it supports technologies from HTTPS - SOAP. Lifetime Updates. Jmeter is configured to create 10 users (threads), Ramp-up in 1 second and repeat that for 3000 times (the idea in this test is to get to know the limits of the server, how many req/sec can handle). Learn Apache JMeter by Example. sh the Docker image can be build from the Dockerfile but this is not really necessary as you may use your own docker build commandline. , in the JMeter GUI). What you may notice is you’re unable to allocate more than 2 GB of memory; this happened to me, JMeter refused to open, and was the cause of the JMeter only being able to use 1 CPU core.