Unable to increase Java heap memory via IntelliJ

Question

Problem:

I run a WSL AlmaLinux with 15_000M allocated RAM, and launch my Java application via IntelliJ, on a OpenJDK 64-Bit.

I need to increase the max heap memory available to my Java application, but it caps at 4_093M.

Attempts:

I have tried to increase the max and initial heap memory:

• By adding:

-Xms12288m
-Xmx12288m

1. To: PATH_TO_INTELLIJ/232.8660.185.vmoptions

2. And to: PATH_TO_INTELLIJ/bin/idea64.vmoptions

• By running:

export _JAVA_OPTIONS="-Xms12288m -Xmx12288m"

• Trying both methods with lower heap memory sizes.

Results:

This did not increased the heap memory as confirmed:

• By the RES field in top:

  PID USER  PR  NI    VIRT     RES    SHR  S  %CPU  %MEM     TIME+ COMMAND
 5123  usr  20   0   9991.9m   3.5g  21896 S 672.7  22.9  74:06.11 java

• By JProfiler:

Profile of a run launched via IntelliJ

• By Runtime.getRuntime().totalMemory():

4093M

If you have any idea (pun unintended), please let me know!