ForkJoinPool.getCommonPoolParallelism() reports always 1

ADDITIONAL SYSTEM INFORMATION :
Win10 20H2 (Build19042.868)
Java: 17-ea+11-835
CPU: i7-8700K

A DESCRIPTION OF THE PROBLEM :
A call to ForkJoinPool.getCommonPoolParallelism() will report "1" on my machine (JDK 16 = 11!)

If you think its a "special" problem on my machine - contact me.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Just run getCommonPoolParallelism()

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Version: java.version: 16, OpenJDK 64-Bit Server VM, 16+36-2231
OS: Windows 10 Version 10.0 (amd64)
CPUs: 12
fjp: 11
ACTUAL -
Version: java.version: 17-ea, OpenJDK 64-Bit Server VM, 17-ea+11-835
OS: Windows 10 Version 10.0 (amd64)
CPUs: 12
fjp: 1

---------- BEGIN SOURCE ----------
public class TestFjp {

public static void main(String[] args) {
System.out.println("Version: " + getJavaVersion());
System.out.println("OS: " + getOsInofrmation());
System.out.println("CPUs: " + Runtime.getRuntime().availableProcessors());
System.out.println("fjp: " + ForkJoinPool.getCommonPoolParallelism());
}

private static String getJavaVersion() {
return "java.version: " //
+ System.getProperty("java.version")//
+ ", " + System.getProperty("java.vm.name")//
+ ", " + System.getProperty("java.runtime.version");
}

private static String getOsInofrmation() {
return System.getProperty("os.name") + " Version "
+ System.getProperty("os.version") + " (" + System.getProperty("os.arch") + ") ";
}
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Using "Runtime.getRuntime().availableProcessors())" won't work on foreign software.

FREQUENCY : always