Parallelizing Java Streams with Virtual Threads: Building vtstream

You know what's funny about parallelStream() in Java? Everyone acts like it's this magic performance switch. Just slap .parallel() on your stream and suddenly your code is running on all your CPU cores, right?

Wrong. Or at least, not in the way you'd want.

parallelStream() uses the common ForkJoinPool. That's a shared, JVM-wide thread pool. Every parallel stream operation in your entire application competes for the same pool. And the pool is sized to your CPU core count — which is perfect for

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