Test with Java 21 and Jmeter

[iandyh]

Currently we are using Jmeter 3.3, according to https://openjdk.org/projects/jdk/21/, we have virtual threads which is supposed to reduce the resource usage per Jmeter process. Currently, it's recommended to keep threads number below 300 per Jmeter process.

So with this issue, we want to know:

1. Whether the new Java 21 can work with Jmeter 3.3
2. If it can, is the behaviour changed? For example, whether 300 threads perform in the same way as it was before
3. If no.2 is the same, then how much resources we can save compared to before
4. Is the 300 limit still a thing?

[rsw-a]

when I checked quickly jmeter 3.3 doesn't work with jdk 21 see below.

❯ sdk use java 8.0.352-amzn

Using java version 8.0.352-amzn in this shell.
❯ java -version
openjdk version "1.8.0_352"
OpenJDK Runtime Environment Corretto-8.352.08.1 (build 1.8.0_352-b08)
OpenJDK 64-Bit Server VM Corretto-8.352.08.1 (build 25.352-b08, mixed mode)
❯ apache-jmeter-3.3/bin/jmeter
================================================================================
Don't use GUI mode for load testing, only for Test creation and Test debugging !
For load testing, use NON GUI Mode:
   jmeter -n -t [jmx file] -l [results file] -e -o [Path to output folder]
& adapt Java Heap to your test requirements:
   Modify HEAP="-Xms512m -Xmx512m" in the JMeter batch file
================================================================================
Warning: the fonts "Times" and "Lucida Bright" are not available for the Java logical font "Serif", which may have unexpected appearance or behavior. Re-enable the "Times" font to remove this warning.
❯ sdk use java 21-tem

Using java version 21-tem in this shell.
❯ java -version
openjdk version "21" 2023-09-19 LTS
OpenJDK Runtime Environment Temurin-21+35 (build 21+35-LTS)
OpenJDK 64-Bit Server VM Temurin-21+35 (build 21+35-LTS, mixed mode)
❯ apache-jmeter-3.3/bin/jmeter
Not able to find Java executable or version. Please check your Java installation.

[iandyh]

@rsw-a Thanks for checking. yes, looks like jmeter 3.3 only supported Java 8. If we want to use new version of Java, looks like we need to go for Jmeter 5.x.

[iandyh]

Let me close this issue as the conclusion is reached.

[iandyh]

Since we start considering upgrade jmeter version, we can start to consider this issue. However, we might need project like this in order for Jmeter to support virtual thread: https://github.com/nirmal-mewada/jmeter-loom

Some people also suggest to Jmeter: apache/jmeter#6029 but no progress so far.