JMETER creates multiple process threads even for Single Thread run

Question

I am running a simple JMETER file with one Thread Group with Single user.

when I look at the background ps -eL | grep jmeter

I get more than 30+ threads for that PID as below. Any suggestion why this is occuring and if there is a way to prevent this?

output of ps -eL | grep jmeter

6380 6380 pts/0 6380 6381 pts/0 6380 6382 pts/0 6380 6383 pts/0 6380 6384 pts/0 6380 6385 pts/0 6380 6386 pts/0 6380 6387 pts/0 6380 6388 pts/0 6380 6389 pts/0 6380 6390 pts/0 6380 6391 pts/0 6380 6392 pts/0 6380 6393 pts/0 6380 6394 pts/0 6380 6395 pts/0 6380 6396 pts/0 6380 6397 pts/0 6380 6398 pts/0 6380 6399 pts/0 6380 6402 pts/0 6380 6403 pts/0 6380 6404 pts/0 6380 6405 pts/0 6380 6406 pts/0 6380 6407 pts/0 6380 6408 pts/0 6380 6409 pts/0 6380 6410 pts/0 6380 6411 pts/0 6380 6412 pts/0 6380 6413 pts/0 6380 6414 pts/0 6380 6415 pts/0 6380 6416 pts/0 6380 6417 pts/0 6380 6419 pts/0 6380 6420 pts/0 6380 6421 pts/0 Sl+ 0:00 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Rl+ 0:02 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:00 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:00 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:00 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:03 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:02 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:02 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:02 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:03 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:02 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:02 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:03 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:01 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:00 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:00 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:00 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:00 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:00 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 1:34 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 1:05 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx Sl+ 0:00 /usr/bin/java -jar /home/manh/inhouse_apps/jmeter/apache-jmeter-5.3/bin/ApacheJMeter.jar -n -t jmx/retail/dev/test_concurrency.jmx

Dmitri T Dmitri T · Accepted Answer · 2021-04-29T09:39:52

One JMeter instance = one Java process, the number of internal threads can be viewed using i.e. JConsole

If you're seeing more than one Java process it means that you (or someone else) started another JMeter instance in non-GUI mode

You might also want to consider upgrading to the latest JMeter version (which is JMeter 5.4.1 as of now) as you're supposed to be using the latest version of JMeter according to Best Practices user manual chapter

JMETER creates multiple process threads even for Single Thread run

1 Answers