Christian Woerz

Java 21: The Revolution of Virtual Threads - A Deep Dive

What if your simple, blocking code could handle millions of requests? See how virtual threads deliver massive scalability without the complexity of reactive programming.

Java 21: The Revolution of Virtual Threads - A Deep Dive
#1about 6 minutes

Building a traditional blocking web application

A live coding demonstration shows how to build a standard blocking API with Spring Boot and how its performance degrades under load.

#2about 5 minutes

Understanding the limitations of platform threads

Creating thousands of traditional platform threads demonstrates their high memory consumption, 1:1 mapping to OS threads, and eventual OutOfMemoryError.

#3about 12 minutes

Improving performance with a reactive approach

Refactoring the blocking API to use asynchronous programming with CompletableFuture solves the performance bottleneck but introduces significant code complexity.

#4about 7 minutes

How virtual threads solve the concurrency problem

Virtual threads are lightweight, JVM-managed threads that run on a small pool of carrier threads, enabling millions of concurrent tasks without high memory overhead.

#5about 4 minutes

Enabling virtual threads in a Spring Boot application

A single configuration flag in Spring Boot 3.2 is all that's needed to switch the application to use virtual threads for handling requests.

#6about 8 minutes

Managing parallel tasks with structured concurrency

StructuredTaskScope provides a modern API to run multiple blocking operations concurrently in separate virtual threads, simplifying parallel code.

#7about 4 minutes

Understanding the limitations of virtual threads

Virtual threads can be "pinned" to their carrier thread by synchronized blocks, native calls, or CPU-intensive tasks, which negates their benefits.

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What's new in the Java 21 LTS release
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What's new in the Java 21 LTS release

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Solving blocking issues with Project Loom's virtual threads
18:22 MIN

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Q&A on Project Loom and integration challenges
23:08 MIN

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Side-by-Side: Reactive vs non-reactive Java

Understanding the goals of Java's Project Loom
01:39 MIN

Understanding the goals of Java's Project Loom

Java's Project Loom & Co - the end for reactive programming?

Introducing lightweight virtual threads in Java 21
07:40 MIN

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Introduction and pitfalls of Java's new concurrency model

Comparing Project Loom with reactive programming
43:51 MIN

Comparing Project Loom with reactive programming

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