Jmeter Heap Error!

Hi All!  
        

While using Jmeter, it is not always like you record script, provide number of threads, add listeners and run the script. I am saying this because so many time when we try run our test, we face some error not all the time but some time when we increase the number of threads. This is usually caused by including memory intensive listeners in your stress test. Listeners like "View Tree Results" are useful for debugging your test, but they are too memory intensive to remain in your test when you ramp up the number of simulated users and iterations. The best listeners to use for a long-term, high-load test are Aggregate Listener, Graph Listener, and Spline Listener.

Here is the image of that particular section where you will find the area where you can make changes to reduce the heap error.

To go to this area, Go to the" Jmeter" folder where you have copied that. Then explore this folder and open "jmeter.bat" with notepad, and find the area mentioned in the image:

Now as you can see in the above image, the heap size, new heap size. Now one important thing, is if you want to test your web application with more that 500 users and your system configuration is only 512 MB Ram or your have 1000 users or more that that and you have 2 GB m/c so it is going to little bit tough for you to run your load test.

Because if a m/c with 2GB ram can generate 1000 user max. Rest your application will get choked because of m/c's slowness. 

Heap size is depends upon your system configuration. So if you have 2GB m/c then increase your heap size to 1024-1024m or 512-1024m, according have much free space you have in your m/c.

You can make changes directly from the area mentioned in the image.

And one most important thing, do not put max load at first instance. First check the behavior of your m/c with less number of users.

Enjoy your load test with Jmeter.   :) 

GUI changes in Jmeter

How does a software works? Is very important. But for the first time user, look and feel of that software is very important. Yes I am talking about GUI.

So many load testing tool like QTP, Load runner, web load etc. are mostly used because of its easy user interface and GUI. However these are paid tools. Now coming to the point, Jmeter the open source load testing tool has released its latest version (2.6).  I think you are still confused if I am talking about GUI then why Jmeter... It is because in the latest version of Jmeter GUI has been changed. Now when you will run Jmeter, you will get this kind of toolbar in your Jmeter window.

  

Jmeter look and feel: Change the look of you Jmeter window as you want from the given options.

Jmeter also have provided the search option. After recording the script, you can easily search the tree content or sampler by typing in search window.

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jmeter latest version 2.6 has been released, with changes

jmeter latest verion 2.6

Jmeter tutorial videos

As discussed in earlier post the jmeter is a load testing tool. Now here are some videos related to jmeter.

These videos consists:-

1. Identifying key scenarios  
2. recording script
3. parameterization
4. data correlation
5. understanding report 

Click here for jmeter tutorials video

How to monitor server,s system performance while running Jmeter

This is the big question , when you are putting load on webserver from your computer or using distributed load testing, what is behaviour of server's computer..Server's computer behaviour means at the time of load what is cpu performane, network performance, i/o. So we need to monitor thise things also. But as i have practiced i was not be able to do distributed load testing and also monitoring the cpu performane of server's computer. For that what you can do?I will tell you waht i have tried. I open two jmeter windows. In one window i did distributed load testing, and in another i used the same script but with single thread (user), and check on forever, and added the server performance monitor listners. What it will do? It will run one user in loop till you will not stop the test and also provide you the server's computer performance. Because one user will create that much diffreence according to me.
First i will tell you have to add plugins in jmeter for listners.

For that you have to download  jmeter plugin.jar for the jmeter version you are using. Now extract jmeter plugin and copy jmeter plugin.jar file to c:/jmeter/lib/ext. And from the extracted file you will also get the server agent folder. Copy the server agent folder to the web server's computer and past it in c: drive. Explore server agent folder at server's end and start start agent.bat file.

Now you should know the server's computer ip. Like we have the server ip is 192.168.45.89.

Now from your computer start jmeter and add-:

After clicking server performance monitor you will see the window like:-

In this window you will be able to see add row,copy row and delete row.And clickig on add row the window will be like:-

Here below Host/Ip where local host is written you have to type the ip of server's computer.And the port will be by default set to 4444 till no changes done at the server end.

Also you will be able to see cpu,memory,swap,disksI/O,NetworksI/O.From here you can select single object at a time.If you want to see all the details at the same time,so you can add server performance monitor from thread group-add-listners,and then can select another object.

Remember first you have to record or open the test then add the listners.

Now when you will start the test you will be able to see the server's performance selecting server performance monitor.

I think this blog may helpful to you for this senario..

Thank you