bitcoincore development – Can I speed up the running of functional tests?

The Bitcoin Core test README states:

By default, up to 4 tests will be run in parallel by test_runner. To
specify how many jobs to run, append --jobs=n

The individual tests and the test_runner harness have many
command-line options. Run test/functional/ -h to see
them all.

Pieter Wuille also explained how he gets the total time down below 4 minutes on GitHub:

You can run them in parallel; if you have sufficient RAM pretty extremely even. -j60 works fine on my 4-core 32 GiB RAM system, taking 3m46s. A lot of the time consists of processes waiting for each other, so it’s not actually CPU bound.