Could anyone help with the explanation of fields of some common listeners in Jmeter.
Can you please elaborate your question, i.e. which common listeners you are talking about like:-
- Aggregate Report
- View Results in tree
- View Results in table
and which fields explanations you need like:-
- Number of Samples (# Samples)
- 90% line
Because JMeter has lots of listeners and a performance tester needs to summarize his/her report in a manner that he/she can target different level of Audience for displaying report like Management report will be different from Developer report. For preparing such reports, one may need to use multiple listeners for creating a Performance report to please every mass of Audience.
Once you update about the name of listeners or their fields you are looking for; will update you about the explanation of fields and you can refer the following links too (from Stack Overflow and Jmeter site) as someone has already asked & answered similar question:-
https://stackoverflow.com/questions/10448516/apache-jmeter-listener-results-interpretation http://jmeter.apache.org/usermanual/component_reference.html#Aggregate_Report http://nico.vahlas.eu/2010/03/30/some-thoughts-on-stress-testing-web-applications-with-jmeter-part-2/
Second Part: Information about the listeners you have asked
1. View Results tree: This listener is used when you want to validate your test, see the HTML response to verify whether, your recorded and modified test (e.g. after using XPath extractor, CSV files) is running correctly or not. If you are not getting the HTML of the expected page then it means that there is some issue with the script.
You can also use this listener for validating the Request posted by the JMeter to server, if you have used a Regular Expression Extractor, then using ‘Request’ tab of this listener you can see what actually has been posted by JMeter. It can also be used for seeing the response of your request i.e. it tell whether the response is ‘OK’, 200 etc. or for errors it tells you ‘500’, ‘404’ and its details. For more information refer to this link http://jmeter.apache.org/usermanual/component_reference.html#View_Results_Tree
But don’t use this listener in actual test, as it consumes a lot of memory.
2. View Results in a Table: As the name suggest this listener provides the table view of the results, instead of grouping samples with their name, it provides the individual result of each sample. Let’s say you execute a test for 100 user load and it contains a request to some Test.aspx page, then using this listener, instead of getting only Average value, you will know the individual response time of each user separately.
You will know the start time of each sample, this is helpful when you are using some timers and want to see whether time is actually working as required or not, as this tells you which request got delayed and by what time.
Again this too is a heavy listener so should not be used while running actual tests. Definitely you can use this listener for digging out more over results, but that can be done even after completing tests, just open your existing .jtl file in this listener and it will give you the table.
3. Summary Report: This is a light weight listener which is actually used for preparing reports, as it shows almost all the required information. It groups the samples based on their name and then provide the average time for grouping. This provides ‘Std. Dev.’ Value for the executed tests, which is required in management reports for Statistical Analysis of the results. You should read about the Variance and Std. Deviation first (if not already know) for knowing this field more as this is very usable field value.
4. Simple Data writer: This is one of the lightest listeners of JMeter which doesn’t display any data but used in script for creating .jtl file, especially when executed in non-GUI mode. This reduces the size of the scripts and consumes less memory, helpful in bigger and heavy load tests. JTL file saved in this listener can be opened in any other in-built listener for creating reports. http://jmeter.apache.org/usermanual/component_reference.html#Simple_Data_Writer
In addition to this you can read about the Plugin listeners of JMeter, most commonly used is the ‘Perfmon Metrics’ this providers information about the resource utilization of the servers (Application and DB servers). Since, Resource Utilization is one of the Key Performance Indicator for determining the performance of system (specially scaling part). Using this you can monitor the CPU, Memory, Network I/O etc. values of servers under test.