OpenJDK Archives - Red Hat Developer

Mandrel: A specialized distribution of GraalVM for Quarkus

By Severin Gehwolf April 14, 2021April 12, 2021

When we first announced Mandrel, we explained why Red Hat needed a downstream distribution of GraalVM. We were most interested in GraalVM’s native image capability, specifically in the context of Quarkus. In this article, we explain what Mandrel is and what it’s not. We’ll introduce some of Mandrel’s technical features and offer a short demonstration of using Mandrel with Quarkus.

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How Red Hat ported OpenJDK to 64-bit Arm: A community history

By Andrew Haley February 1, 2021January 29, 2021

It has been quite a year for Arm Ltd., the firm that designs reduced instruction set computing (RISC) architectures for computer processors. The news that Arm-based computers will be important for the foreseeable future has even reached the mainstream media. At the end of 2019, Amazon Web Services announced Arm-based Graviton2 servers. In June 2020, Apple announced its plans to move Macintosh computers over to Apple silicon—which means Arm.

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Introduction to ContainerJFR: JDK Flight Recorder for containers

By Andrew Azores January 25, 2021January 21, 2021

OpenJDK has long been a top pick for real-world applications and workloads, chosen for its blend of performance, compatibility, reliability, and observability. For many years, JDK Flight Recorder (JFR) and JDK Mission Control (JMC) have contributed to OpenJDK’s success. Until recently, both were commercial features, however, available only for certain users and workloads.

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Installing Red Hat’s migration toolkit for applications on your laptop

By Miguel Pérez Colino December 15, 2020December 14, 2020

If you are a developer considering modernizing your Java applications by containerizing or migrating them to a more modern application server, then you are likely aware of Red Hat’s migration toolkit for applications. This article helps you get started with migration toolkit for applications by installing it directly on your laptop. For more about the toolkit, see:

Note: Red Hat’s migration toolkit for applications (formerly Red Hat Application Migration Toolkit) is based on the upstream, open source Windup project. Check out the code and see how it works!

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Collect JDK Flight Recorder events at runtime with JMC Agent

By Mario Torre and Kangcheng Xu and Jessye Coleman-Shapiro October 29, 2020December 4, 2020

JDK Flight Recorder, or JFR, is an event-based production environment profiler available from OpenJDK 8u272 forward. Being a HotSpot-native feature, JDK Flight Recorder performs with extremely low overhead in terms of how it uses both space and time.

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Checkpointing Java from outside of Java

By Christine Flood October 15, 2020February 4, 2021

When OpenJDK‘s Java virtual machine (JVM) runs a Java application, it loads a dozen or so classes before it starts the main class. It runs a method several hundred times before it invokes the optimizing compiler on that method. This preparation is a critical component of Java’s “write once, run anywhere” power, but it comes at the cost of long startup times.

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Migrate your Java apps to containers with Migration Toolkit for Applications 5.0

By Miguel Pérez Colino September 4, 2020October 28, 2020

As a developer, you have probably experimented with Kubernetes. It’s also possible that you are already running several Java applications on a Kubernetes platform, maybe Red Hat OpenShift. These initial containerized applications were greenfield projects, where you enjoyed the benefits of a platform providing templated deployments, easy rollbacks, resource availability, security by default, and a manageable way to publish your services.

Now, you might be thinking, “How can I enjoy all of these benefits in my existing Java applications?” Most Java applications in production today are running on virtual machines (VMs), likely on an application platform that is not container friendly. So, how can you migrate them from the current platform to containers on Kubernetes?

It isn’t an easy task, but this is a problem that we have been working hard on for years. Red Hat’s Migration Toolkit for Applications (MTA) 5.0 is the latest resulting iteration: An assembly of tools that you can use to analyze existing applications and discover what is required to modernize them. Read on to learn MTA 5.0’s features and migration paths.

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Get started with JDK Flight Recorder in OpenJDK 8u

By Mario Torre August 25, 2020August 18, 2020

The OpenJDK 8u 262 release includes several security-related patches and a new addition, JDK Flight Recorder (JFR). This article introduces OpenJDK developers to using JDK Flight Recorder with JDK Mission Control and related utilities. I will also briefly introduce you to Project Hamburg, also known as Container JFR.

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Debugging GraalVM-native images using gdb

By Andrew Dinn June 25, 2020June 25, 2020

The GraalVM project includes, amongst other capabilities, a component called GraalVM Native Image. GraalVM Native Image supports the delivery of Java applications as shrink-wrapped, self-contained, standalone executables, commonly referred to as Java-native images. Native images often have a smaller footprint and faster startup time compared to running the same application in the traditional way on the JVM. This is often a win for short-running applications or small, container-based services. The trade-off is usually lower peak performance for long-running programs, and higher garbage collection overheads and latencies for programs with large amounts of resident data.

We are especially interested in GraalVM-native images as an alternative back-end delivery option for applications based on Quarkus. The Java team has worked hard to ensure that Quarkus is well integrated with GraalVM Native Images. In the process, they have found that one important usability issue is the ability to debug the delivered native image.

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The road to Quarkus GA: Completing the first supported Kubernetes-native Java stack

By Mark Little June 4, 2020June 25, 2020

I’ve had many proud moments in my role here at Red Hat over the years. Examples include when we released the first version of WildFly, when we acquired the Camel team, when we worked with other vendors to create Eclipse MicroProfile, the great work the Strimzi team did to get into the Cloud Native Computing Foundation, our entire Red Hat Managed Integration effort, Kogito, and the list goes on. I feel like I add to this list of examples on an almost weekly basis.

Well, I can now update this list with the first product release of Quarkus, formally called the Red Hat build of Quarkus. (You can also find more support options on the Quarkus project site.) It should come as no surprise that Quarkus is on this list. I suppose what might surprise some people is that Quarkus is only just a product now. Given all of the activities since we officially launched the Quarkus project in 2019, you could be forgiven for thinking it was already a product.

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