Inside Java

Allocating Off-Heap Memory: Typically 6-18x Faster in JDK 28

2026-10-23T00:00:00Z

Pooled confined arenas provide a significant performance improvement for short-lived native allocations.

What's Going Wrong with My JVM?! A Guide to First-Time Failure Diagnosis

2026-10-22T00:00:00Z

It's 2 AM Friday night when you get alerts your primary business application stopped responding and user tickets are piling up. For situations like these, you need to have already captured the data that can help you quickly get a sense of what's going wrong. Yet many production environments don't have such data collection enabled, and some diagnostics have performance costs that are unsuitable for many production applications. In this session, we’ll use some commonly reported Java heap memory problems to show how to collect and analyze some low-cost data to diagnose those problems at first-time failure.

JEP targeted to JDK 28: 543: Structured Concurrency

2026-10-21T00:00:00Z

The following JEP is targeted to JDK 28: 543: Structured Concurrency

Reflect, Transform, Accelerate: Bringing GPU Computing to Java

2026-10-20T00:00:00Z

Java’s code reflection API, developed in OpenJDK Project Babylon, opens a new path to targeting foreign programming models directly from Java—including GPUs. This talk introduces the Heterogeneous Accelerator Toolkit (HAT), a Java parallel programming framework that accelerates modern workloads on specialised hardware through three core stages: reflect, transform, and accelerate. Through examples of tensor-core programming and matrix multiplication—fundamental building blocks for AI and natural-language processing—we demonstrate HAT in action. We also explore performance analysis and tuning of the CUDA backend with NVIDIA Nsight Compute and Nsight Systems, from profiling generated kernels to identifying optimisation opportunities.

JEP targeted to JDK 28: 546: Adaptive Heap Sizing for ZGC

2026-10-19T00:00:00Z

The following JEP is targeted to JDK 28: 546: Adaptive Heap Sizing for ZGC

Episode 72 “OpenJDK Bug Fixing, JavaOne, and JDK 28” [IJN]

2026-10-17T00:00:00Z

A critical bug in JDK 27 and how it was fixed, some conference news, and how JDK 28 is shaping up

JEP targeted to JDK 28: 545: Faster Startup and Warmup with ZGC

2026-10-16T00:00:00Z

The following JEP is targeted to JDK 28: 545: Faster Startup and Warmup with ZGC

How Does Java Fit Into the World of AI—and How Can It Become an Even Better Fit?

2026-10-15T00:00:00Z

In this video, we discuss why Java is already a good choice for AI and how existing and future Java platform features can make it even stronger. We explore developments across the language, libraries, and runtime, including OpenJDK Projects Amber, Babylon, Valhalla, and Panama, along with smaller improvements that can have a big impact when combined.

Everyday JSON in Java

2026-10-14T00:00:00Z

JSON is ubiquitous in modern software, and many use cases are just too small to justify adding external dependencies. To address these everyday use cases, a new JEP proposes a simple, incubating API for parsing, navigating, and generating JSON documents-both for Java developers and for the JDK itself. While the Java ecosystem offers many libraries with JSON-processing capabilities, this built-in API is not intended to replace them, but rather to offer a low-friction option when an external library would be unnecessary or impractical. In this talk, we will show how Data-Oriented Programming helps simplify the API, discuss its intended use cases, outline the design trade-offs, and demonstrate its capabilities.

Structured Concurrency Looms

2026-10-12T00:00:00Z

Structured Concurrency is the next major feature from Project Loom. In this session, we will explain the motivation and design of structured concurrency, show how to use it effectively, and discuss the lessons learned as the feature evolved. We'll also look beneath the surface at the new lower-level API behind the latest design, offering an early glimpse of work that is expected to form the basis of a future lower-level structured concurrency API.