WeAreDevelopers LIVE • Sep 14, 2023

Introduction and pitfalls of Java's new concurrency model

David Vlijmincx

Are you accidentally paralyzing your Java 21 applications? Discover why pooling virtual threads is an anti-pattern and how to avoid thread pinning to maximize system throughput.

Pause

Mute

Enter Fullscreen

#1 about 5 min

Analyzing the traditional Java platform thread model

The legacy Java threading model uses OS-managed platform threads that consume excessive memory and delay processing.

#2 about 4 min

Managing thread resources with executor service pools

Utilizing executor service pools enables thread reuse but can introduce state leaks and structural blocking inefficiencies.

#3 about 2 min

Introducing virtual threads for lightweight concurrency allocation

Virtual threads eliminate core memory allocation limits by utilizing a resizable heap design natively administered within the JVM.

#4 about 3 min

Comparing memory usage between platform and virtual threads

A memory utilization benchmark demonstrates how virtual threads seamlessly scale to support one hundred thousand parallel execution tasks.

#5 about 6 min

Creating and executing virtual threads in Java code

Implementing virtual thread constructors and specialized executor interfaces simplifies massively parallel programming workflows.

#6 about 6 min

Thread mounting and carrier thread execution processes

Carrier threads manage JVM virtual threads via fork-join pools that handle automatic mounting limits during blocking operations.

#7 about 3 min

Recognizing common virtual thread operational pitfalls and limitations

Pooling virtual threads or leveraging them for continuous CPU-bound computations reduces their scaling effectiveness and introduces overarching failures.

#8 about 6 min

Analyzing the risks of unstructured parallel thread behavior

Failing to declare explicit task relationships often creates orphaned threads and wastes execution resources during unexpected errors.

#9 about 7 min

Managing thread lifecycles using structured task scopes

The Java StructuredTaskScope object explicitly controls thread intent through embedded success validation and automated failure shutdown directives.

#10 about 7 min

Building custom structured task scopes for dynamic thread completion

Extending the base scope object enables advanced threshold logic that safely cancels competing threads upon finding designated successful criteria.

#11 about 10 min

Exploring reactive programming implications and virtual thread usage

Common implementation concerns highlight specific ecosystem boundaries around framework migrations, reactive programming displacement, and thread-local modifications.

Matching moments

2:23 min

Simplifying concurrent code with Java 21 virtual threads

Jan Weinschenker

Jan Weinschenker · World Congress 2024

2:19 min

Key takeaways for adopting virtual threads in Java

Christian Woerz · LIVE

3:49 min

Scaling concurrent applications using lightweight virtual threads

Ron Veen

Ron Veen · World Congress 2023

3:08 min

Refactoring concurrent operations using the structured task scope

Filip Egeric

Filip Egeric · World Congress 2026 Europe

1:00 min

Introduction to the native Java structured task scope API

Filip Egeric

Filip Egeric · World Congress 2026 Europe

10:03 min

Addressing updates on concurrency extensions and code diagnostics

Mohamed Taman · LIVE

More from WeAreDevelopers LIVE

WeAreDevelopers LIVE - How DevRel Makes Tech More Human thumbnail

WeAreDevelopers LIVE - How DevRel Makes Tech More Human

Chris Heilmann, Daniel Cranney

Fake or News: Smart Glasses in Court, Medical Advice Watches & Mushroom Electonics - Jason Torres thumbnail

Fake or News: Smart Glasses in Court, Medical Advice Watches & Mushroom Electonics - Jason Torres

Chris Heilmann, Daniel Cranney

Aliens in Quarantine, Python Deprecates Loops, and AI Buys Old Books - Zbyszek Tenerowicz thumbnail

Aliens in Quarantine, Python Deprecates Loops, and AI Buys Old Books - Zbyszek Tenerowicz

Chris Heilmann, Daniel Cranney

WeAreDevelopers LIVE - Node and Package Security thumbnail

WeAreDevelopers LIVE - Node and Package Security

Chris Heilmann, Daniel Cranney, Zbyszek Tenerowicz

WeAreDevelopers LIVE - Streaming HTML thumbnail

WeAreDevelopers LIVE - Streaming HTML

Chris Heilmann, Daniel Cranney, Jad Joubran

WeAreDevelopers LIVE - CODE100 at WeAreDevelopers Europe thumbnail

about 1 month ago

WeAreDevelopers LIVE - CODE100 at WeAreDevelopers Europe

Chris Heilmann, Daniel Cranney, Justin Halsall, Werner Jeschko, Nicole Jeschko, Mirco Tomić

Upcoming sessions on this topic

World Congress 2026 North America

Your Thread Pool Is Lying to You — Sizing Concurrency from Rate Limits and Latency, Not Guesswork

Ratul Ghosh

Intuit, Tech lead and architect for GenOS platform

Ratul Ghosh

World Congress 2026 North America

Look What Java Can Do Now: Live-Coding a GenAI MCP Server with the JAQ Stack

Suren Konathala

Senior Engineering Leader, Marketing & AdTech, AI GTM & Digital Experience Platforms, Java x AI

Suren Konathala

World Congress 2026 North America

When Humans Stop Writing Code: Rethinking Languages, Compilers, and Responsibility

Simon Auer

Organizer of flutter vienna meetup and CEO of marqably

Simon Auer

World Congress 2026 North America

Merging at Scale: From Broken Builds to Green Mainline

Manjari Akella, Preetam Dwivedi

Manjari Akella

Preetam Dwivedi

World Congress 2026 North America

Designing APIs That Survive AI Agents at Scale

Phani Pendurthi

Mastercard, Principal Software Engineer

Phani Pendurthi

World Congress 2026 North America

Beyond Vibe Coding: Using CLI Tools as Your AI Counterpart in Pair Programming

Ron Veen

Java enthusiast and Special agent for Team Rockstars IT

Ron Veen

Related videos

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

LIVE • over 2 years ago

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

Christian Woerz

Beyond Loom: Practical Patterns for Virtual Threads, Structured Concurrency and Reactive Interop thumbnail

Europe 2026 Virtual • about 2 months ago

Beyond Loom: Practical Patterns for Virtual Threads, Structured Concurrency and Reactive Interop

Ivan Šarić

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

World Congress 2024 • about 2 years ago

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

Jan Weinschenker

Modern Java thumbnail

World Congress 2024 • almost 2 years ago

Modern Java

Ron Veen

Structured Concurrency in Practice: CoroutineScope vs StructuredTaskScope thumbnail

World Congress 2026 Europe • about 1 month ago

Structured Concurrency in Practice: CoroutineScope vs StructuredTaskScope

Filip Egeric

Modern Java: This is not your father's Java anymore thumbnail

World Congress 2023 • almost 3 years ago

Modern Java: This is not your father's Java anymore

Ron Veen

Related articles

SH

Severine Hierso

The Concept of Concurrency & Multithreading: What Are They And How They Function

As the world around us moves ever more online, the need for software engineers is growing - seemingly by the hour. Whether by building firewalls that fend off the next big data breach, or developin...

over 4 years ago

The Concept of Concurrency & Multithreading: What Are They And How They Function

BB

Benedikt Bischof

Using Java 17 latest features in real world projects

Welcome to this issue of the WeAreDevelopers Live Talk series. This article recaps an interesting talk by Ron Veen who introduced the audience to some of the most interesting features that got adde...

almost 4 years ago

Using Java 17 latest features in real world projects

IK

Igor Khokhriakov

CH

Chris Heilmann

How We Built a Worry-Free System That Runs for 10+ Years – And What We’d Do Again

The Problem: Big Science, Tiny Teams Between 2012 and 2016, we built a control system for high-throughput tomography beamlines at PETRA III (DESY, Hamburg) and FRM II (Munich) – facilities where re...

11 days ago

Duke, the Java Mascot chilling on the beach

TL

Thomas Limbüchler

93 Java Interview Questions You Should Prepare For

You’re looking to get hired as a Java developer? Good call! Java is used everywhere and provides numerous job opportunities, not only for juniors, but especially for intermediates and seniors. Acco...

almost 6 years ago

93 Java Interview Questions You Should Prepare For

From learning to earning

Jobs that call for the skills explored in this talk.

Software Engineer, Platform Engineering (L2)

San Francisco, CA, United States

Starter $116k–146k Remote YAML Golang Docker

Principal Software Engineer

Indianapolis, IN, United States

Remote NoSQL Docker Twilio

Cloud Foundations Team

Experienced Remote Ruby Golang Puppet

Software Engineer L3

Indianapolis, IN, United States

Expert Remote Redis NoSQL Twilio

Principal Software Engineer, Enterprise AI Platform

Expert Remote Ruby Golang Github

Remote Senior Software Engineer

Expert Remote Twilio Backend Graphql