Apache Jmeter has the -l option for logging the results. However, it creates a single file. If the test is run for quite some time, this log file becomes huge and it takes time to process this file. Is there a way where we can rotate the log file based on file size?
As of current JMeter version 5.2.1 it is not possible, the options are in:
Use i.e. split program to break up large .jtl file into smaller pieces. More information:
How to Split Large Text File into Smaller Files in Linux
Don't use .jtl results file and switch to Backend Listener so the results would go to external database and you can interactively choose smaller chunks, perform filtering, etc. More information:
Real-time results
How to Use Grafana to Monitor JMeter Non-GUI Results
Related
I have the following Test Plan:
Test Plan
Thread Group
Java Request
CSV Data Config Set
My Thread Group has 1 thread looping forever. To my understanding, the thread should go down the CSV file line by line, 1 line per loop. However, it stays on the same first line. If I have two threads, then the first thread will stay on the first line, second thread on the second line, and so on.
I have tried all the different options in CSV Data Config Set (even if it doesn't make sense to try those options) including:
Checked path to file is correct
Tried file encoding as empty, UTF-8, UTF-16
Checked delimiter was correct in CSV
Checked variable names were correct
Allow quoted data true and false
Recycle on EOF true and false
Stop thread on EOF true and false
Tried all sharing modes
I also ensured the CSV file had no empty lines. I am using JMeter 2.13 and the line break character in the CSV is CR LF if that helps.
I've looked at tutorials and other JMeter questions on here, it seems that by default the threads should go down the CSV file. I remember it was behaving properly awhile back, unsure when it started behaving this way.
It is hard to say anything without seeing the code of the Java Request sampler to read the variable from the CSV and your CSV Data Set configuration.
If you want each thread to read the next line from the CSV file each iteration you need to set the Sharing Mode to All Threads
Try using other sampler, i.e. Debug Sampler as it might be the case your approach to reading the variable from the CSV file is not valid
According to JMeter Best Practices you should always be using the latest version of JMeter and you're sitting on a 4-years-old version, it might be the case you're suffering from an issue which has been already fixed so consider migrating to JMeter 5.1.1 or whatever is the latest stable JMeter version available at JMeter Downloads page
I try to remove result files from a listener but it won't work. It seems JMeter lock the result files in runtime.
The screenshot below shows that I save the result to a csv file 'raw-result-table.csv'.
In Setup Thread, I add an OS Sampler to remove the result files. See screenshot below.
It cannot remove the files. I think it is because JMeter lock the file in runtime.
Please note that the OS Sampler is correct. It can remove the files when I disable the thread 'AD'. I've tried BeanShell script and result is the same.
Actually you won't be able to delete the file which is being used for storing results of the current session. Also there are some issues with your test design:
You should not be using any Listeners, especially View Results in Table / Tree, they consume a lot of resources and may ruin your test.
You should be running your test in command-line non-GUI mode. You can combine it with deleting the previous results file like:
del *result*.csv && jmeter -n -t test.jmx -l result.csv
Upon test completion you can open result.csv file in JMeter GUI and perform the analysis.
You should be using JSR223 Test Elements and Groovy language instead of Beanshell (same applies to the functions, you should substitute __Beanshell() function with __groovy() function) as Groovy has much better performance
I am running a stability test (60hrs) in Jmeter. I have several graphs in the test plan to capture system resources like cpu, threads, heap.
The size of View_Results_Tree.xml file is 9GB after 24hrs. I am afraid if jmeter will sustain for 60hrs.
Is there size limit for View_Results_Tree.xml or results folder size in Jmeter?
What are the best practices to be followed in Jmeter before running such long tests? I am looking for recommended config/properties for such long tests.
Thanks
Veera.
There is no results file limit as long as it fits into your hard drive for storing or in your RAM to open and analyze.
The general recommendations are:
Use CSV format instead of XML
Store only those metrics which you need to store, saving unnecessary stuff causes massive memory and disk IO overheads.
If you look into jmeter.properties file (located in JMeter's "bin" folder) for properties which names start with jmeter.save.saveservice i.e.
#jmeter.save.saveservice.output_format=csv
#jmeter.save.saveservice.assertion_results_failure_message=true
#etc.
Copy them all to user.properties file, set "interesting" properties to true and others to false - that will allow to save a lot of disk space and release valuable resources for the load testing itself.
See 9 Easy Solutions for a JMeter Load Test “Out of Memory” Failure for more detailed explanation of the above recommendations and few more JMeter performance tuning tweaks.
There are not limits on file size in JMeter, the limit is your your disk space.
From the file name, I guess you chose XML output, it is better to choose CSV output (see below another reason for that).
Besides, ensure you're not using GUI for load testing in JMeter which is a bad practice, this will certainly break your test if you do it.
Switch to Non GUI mode and ensure you follow those recommendations.
/bin/jmeter -t -n -l /results.csv
Since JMeter 3.0, you can even generate report at end of load test of from an existing CSV (JTL, not from XML format) file, see:
http://jmeter.apache.org/usermanual/generating-dashboard.html
As you need GUI for monitoring, run Jmeter in GUI mode only for the monitoring part.
I agree with the answer provided by UBIK LOAD PACK. But in case if you need to have the results stored somewhere you don't need to worry about the size of the file. The best solution is using Grafana and Graphite (InfluxDB) for realtime reports and efficient storage.
Since SUREFIRE-938 the output of test is buffered in /tmp/stdout*deferred in order to create XML report. I am not interested in the report in XML or any other form, but I gather gigabytes of logs during the test executions, and write them to /tmp, too. Sometimes the total size of both buffer file and the output log is too big and it won't fit - is there a way to disable the report and all this buffering (which slows down the test as well)?
I am running jmeter through the command line, and generating a jtl log file. The last couple of runs, it seems that it has created a couple of different .jtl files, with one of them starting in the middle of the run. Is there a Maximum Length of a Log File, or has anyone seen anything like this before?
Thanks
The JTL files can grow as large as they need to be. In some cases my tests yield JTL files over 25 gigs in size.
However, if you do not change the JTL name between runs it will append to the file, not overwrite. Is it possible you are looking at two test runs in a single JTL file? You would see a big chunk where it looks like there are no results.
If you are running from command line, my suggestion would be to build a shell or batch script that auto timestamps the jtl parameter and starts the test. This way you are guaranteed, without any thinking, to have new files for each run.
Also, just so you are aware: There is a nice plugin jar that will allow you to generate awesome graphs from a raw JTL file!
http://jmeter-plugins.org/wiki/JMeterPluginsCMD/