Skip to main content

Tips to Counter JMeter Out of Memory Error

Often while running load test with too many users, JMeter may experience out of memory error. Reasons for this error could be many. And troubleshooting the error takes a significant amount of time. Therefore to help you in debugging JMeter out of memory error, here we have listed down some possible culprits and some solutions to counter them.

Let’s check out each of them in detail.
  • Heap memory: JMeter may require more Heap memory than the allocated. It is set to 512 MB by default. You can increase that limit to allow more Heap memory to JMeter. For this, edit your jmeter.bat file in any editor and change values of “set HEAP=-Xms512m -Xmx512m” parameter.
  • GUI mode: If you are not debugging your JMeter script, it is advisable to run it in Non-GUI mode. Click here to know more about it. Running JMeter in Non-GUI mode ensures less resource consumption.
  • Listeners: Disable listeners such as Graph Result, View Result Tree which requires more system resources. Only use these listeners if you are debugging your JMeter script.
  • JMeter version: Always use latest version of JMeter as they come with stability and performance improvements.
  • Post-processors: Post processors in your JMeter script consumes resources. Use them wisely and efficiently. Disable/Remove them if they are not required.
  • Script complexity: Make sure your JMeter script is not unnecessarily complex. JMeter will hog much more resources if your script happens to be complex. Consider taking necessary steps to simplify your script.
  • Your system upgrade: If all else fails, consider upgrading your system CPU/RAM as it may be the cause of bottleneck.
Did you find the above tips to counter JMeter out of memory error useful? Do you know any more possible solution to tackle this problem? If you have any more suggestions, do share with us using comments below.

Comments

Popular posts from this blog

JMeter Exceeded Maximum Number of Redirects Error Solution

While running performance test, JMeter allows maximum 5 redirects by default. However, if your system demands more than 5 redirects, it may result in JMeter exceeded maximum number of redirects error. In this post, we have listed down steps to overcome this error. Actual error in JMeter: Response code: “Non HTTP response code: java.io.IOException” Response message: “Non HTTP response message: Exceeded maximum number of redirects: 5” This error is noticed because  JMeter  allows maximum 5 redirects by default and your system may be using more than 5 redirects. You need to increase this count to more than 5 in jmeter.properties file. Follow below steps to achieve this. Navigate to /bin directory of your JMeter installation. Locate jmeter.properties file and open it in any editor. Search for “httpsampler.max_redirects” property in opened file. Uncomment the above property by removing # before it. Change to value to more than 5 Eg. 20. Save the file and restart JMet...

Performance Testing in the Cloud with JMeter & AWS

JMeter is a wonderful tool  to stress test your website and  your application architecture , however if you are trying to simulate many users (>1000) one JMeter instance (=pc) will not be sufficient. You will have to set up a JMeter cluster with multiple machines. JMeter is capable or running  distributed tests , but it comes with limitations. Since most of us don’t have multiple servers laying around somewhere, we usually go to cloud service providers like  AWS , spin up a couple of  EC2 instances  and turn them off whenever we’re done. Here is the problem, JMeter uses  Java RMI (Remote Method Invocation)  to communicate to its slaves, but these connections require all machines to be on the same subnet and this is not feasible with EC2 instances. Below, I explain how to get around this problem using a 3 node configuration in AWS to execute tests. I assume that you have a written the test already and have the .jmx file r...

Difference Between Redirect Automatically and Follow Redirects in JMeter

In this post, we will highlight important difference between Redirect Automatically and Follow Redirects options. These options are found in HTTP Request sampler of JMeter. Knowing the difference will help you decide your performance test strategy. When you check Redirect Automatically option, JMeter will not consider redirect as separate HTTP request. This in turn may result as lower response time in your overall performance test. Whereas Follow Redirect option will consider each redirection as separate requests. This may result in comparatively higher response time. This only has any effect if “Redirect Automatically” is not enabled. To see the difference between these two, record a sample script and run it by checking Redirect Automatically and Follow Redirects option. The second option will generate more requests in your result listener. As you can see from the above post, knowing the difference between Redirect Automatically and Follow Redirects option makes difference i...