Why is default value of "-threads 1"?

[adangel]

Description:
While doing the performance tests, I noticed, that we run PMD from CLI by default only with one thread. This is correct according to the documentation: https://pmd.github.io/latest/pmd_userdocs_cli_reference.html#threads

But, why don't we use the number of available cpus? That would make run PMD faster by default already...

We use "1" here:

pmd/pmd-core/src/main/java/net/sourceforge/pmd/cli/PMDParameters.java

Lines 54 to 56 in 130fee6

	@Parameter(names = { "-threads", "-t" }, description = "Sets the number of threads used by PMD.",
	validateWith = PositiveInteger.class)
	private int threads = 1;

We use "all available CPUs" here:

pmd/pmd-core/src/main/java/net/sourceforge/pmd/PMDConfiguration.java

Line 85 in 130fee6

private int threads = Runtime.getRuntime().availableProcessors();

But this value is not used, when running from CLI, the value of PMDParameters overwrites it.

Are there any reasons, why we should not change this?