Why does JMeter always have only one thread

Question

I deployed JMeter (v5.6.2) on my Centos7 (8C16G) and tried to do some tests with it.

I created a Thread Group, which contains a HTTP request.

However, it seems that the process of JMeter always has only one thread no matter how I configure it.

The Thread Group is configurable with three config variables: Number of Threads (users), Ramp-up period and Loop Count/Infinite.

I've tried to configure them to 50, 5 and Infinite. But it still has only one thread. Because cat /proc/<pid>/status always shows me Threads: 1.

Answer 1

It shouldn't be the case, Java threads should map 1:1 to POSIX threads (unless you're using custom JMeter utilizing project Loom features) plus Java itself will run some internal threads. Anyway I cannot reproduce your issue, maybe your <pid> is wrong?

Also be aware that according to 9 Easy Solutions for a JMeter Load Test “Out of Memory” Failure article you should always be using the latest version of JMeter so consider upgrading to JMeter 5.6.3 (or whatever is the latest stable version which is available at JMeter Downloads page)