Java 21 LTS High-Throughput Concurrency: Virtual Threads, Scoped Values & Carrier Pinning

Project Loom Virtual Threads (JEP 444) decouple Java threads from OS kernel threads, allowing applications to launch 1,000,000+ concurrent threads. Learn how to diagnose Carrier Thread Pinning and replace ThreadLocal with Scoped Values (JEP 446).

1. Executing Tasks with Virtual Thread Executors

try (var executor = Executors.newVirtualThreadPerTaskExecutor()) {
    IntStream.range(0, 10_000).forEach(i -> {
        executor.submit(() -> {
            // High-throughput blocking I/O operation
            Thread.sleep(Duration.ofSeconds(1));
            return i;
        });
    });
} // Auto-joins all virtual threads upon scope exit