Gunnar Morling

This question came up on the Data Engineering sub-reddit the other day: Can Debezium lose any events?

Table of Contents What is CDC?

The other day at work, we had a situation where we suspected a thread leak in one particular service, i.e. code which continuously starts new threads, without taking care of ever stopping them again.

Table of Contents 📦 Distribution 📆 Version 🔧 Installation 💡 Your First Java Program 📚 Learning the Language 👷‍♀️ Build Tool 📝 Editor 🧱 Libraries 🐢 Application Framework 🐳 Container Base Image 🔭 Next Steps 27 years of age, and alive and kicking — The Java…

I strongly believe that you should avoid connecting to production environments from local developer machines as much as possible.

Table of Contents Emitting Custom Events Filtering "Thread Park" Events Towards Real-Time Analysis of JFR Events Java’s BlockingQueue hierarchy is widely used for coordinating work between different producer and consumer threads.

As part of my new job at Decodable, I am also planning to contribute to the Apache Flink project (as Decodable’s fully-managed stream processing platform is based on Flink).

Table of Contents Using Logical Decoding Row Filters With Debezium Observing Filtered Change Events Wrap-Up This post originally appeared on the Decodable blog.

Table of Contents The Observation The Solution Take Away While working on a demo for processing change events from Postgres with Apache Flink, I noticed an interesting phenomenon: A Postgres database which I had set up for that demo on Amazon RDS, ran out…

Table of Contents Java Applications on Render Configuration Details Docker Hub Access Token GitHub Actions This is a quick run down of the steps required for running JVM applications, built using Quarkus and GraalVM, on Render.

Table of Contents The Space: Real-Time Stream Processing The Environment: A Start-up The Team: One of a Kind Outlook It’s my first week as a software engineer at Decodable, a start-up building a serverless real-time data platform!

Table of Contents Standalone or Distributed?

Table of Contents Unit Tests Integration Tests Wrap-Up Kafka Connect is a key factor for the wide-spread adoption of Apache Kafka: a framework and runtime environment for connectors, it makes the task of getting data either into Kafka or out of Kafka sole…

Table of Contents 1. 💦 Rehearse, Rehearse, Rehearse 2. 🎬 Start With a Mission 3. 📖 Tell a Story 4. 👀 Look at the Audience, Not Your Slides 5. 🧹 Put Less Text on Your Slides.

Table of Contents Project Loom Scheduling Discussion Project Loom (JEP 425) is probably amongst the most awaited feature additions to Java ever; its implementation of virtual threads (or "green threads") promises developers the ability to create highly co…

JDK Mission Control (JMC) is invaluable for analysing performance data recording using JDK Flight Recorder (JFR).

Table of Contents FAQ When it comes to code reviews, it’s a common phenomenon that there is much focus and long-winded discussions around mundane aspects like code formatting and style, whereas important aspects (does the code change do what it is supposed

The JDK Flight Recorder (JFR) is one of Java’s secret weapons; deeply integrated into the Hotspot VM, it’s a high-performance event collection framework, which lets you collect metrics on runtime aspects like object allocation and garbage collection, class

Table of Contents Context The Error Itself Mitigation General Best Practices As software developers, we’ve all come across those annoying, not-so-useful error messages when using some library or framework: "Couldn’t parse config file", "Lacking permission…

Table of Contents Discussion and Outlook 🧸 It’s Casey.

Table of Contents The Challenge The OSS Quickstart Archetype Outlook I am very happy to announce the availability of the OSS Quickstart Archetype!

The other day, I came across an interesting thread in the Java sub-reddit, with someone asking: "Has anyone attempted to write logs directly to Kafka?".

Table of Contents The Problem Bridge Methods to the Rescue Creating Bridge Methods Ourselves If you work on any kind of software library, ensuring backwards-compatibility is a key concern: if there’s one thing which users really dislike, it is breaking ch…

If you have followed this blog for a while, you’ll know that I am a big fan of JDK Flight Recorder (JFR), the low-overhead diagnostics and profiling framework built into the HotSpot Java virtual machine.

Table of Contents Don’t Fear Outdated Caches – Change Data Capture to the Rescue!

Table of Contents The Screen Compute Cameras Work in Progress: Teleprompter Lighting Audio What’s Next?

Table of Contents Including Snippets From Your Test Directory Summary It has been just a few weeks since the release of Java 17, but the first changes scheduled for Java 18 begin to show up in early access builds.

Table of Contents The ResourceBundleProvider Interface Resource Bundle Providers Running on the Classpath Discussion and Wrap-Up The ResourceBundle class is Java’s workhorse for managing and retrieving locale specific resources, such as error messages of…

Table of Contents Getting Started With JfrUnit Groovier Tests With Spock Outlook Unit testing, for performance It’s with great pleasure that I’m announcing the first official release of JfrUnit today!

Table of Contents Cambrian Explosion of Connectors Democratization of Data Pipelines Stream Processing for Everyone Honorable Mentions Over the course of the last few months, I’ve had the pleasure to serve on the Kafka Summit program committee and review…

Table of Contents Trying ZK-less Kafka Yourself Taking Brokers Down Wrap-Up Sometimes, less is more.

One of the ultimate strengths of Java is its strong notion of backwards compatibility: Java applications and libraries built many years ago oftentimes run without problems on current JVMs, and the compiler of current JDKs can produce byte code, that is ex…

Table of Contents What’s SIMD Anyways?

Table of Contents The Postgres JDBC Driver The Vert.x Postgres Client Other Use Cases Reading a blog post about what’s coming up in JDK 16 recently, I learned that one of the new features is support for Unix domain sockets (JEP 380).

Table of Contents The Example The API Signature Check jlink Plug-in Summary Discussions around Java’s jlink tool typically center around savings in terms of (disk) space.

Table of Contents How to Prevent This Situation?

Table of Contents Getting Started With JfrUnit Case Study 1: Spotting Increased Memory Allocation Case Study 2: Identifying Increased I/O With the Database Discussion Summary and Outlook Functional unit and integration tests are a standard tool of any sof…

Table of Contents Creating a Modular Runtime Image for a Quarkus Application Adding an AppCDS Archive to a Custom Runtime Image Creating a Linux Container Image Let’s See Some Numbers!

Table of Contents Bonus: Schema Creation The Testcontainers project is invaluable for spinning up containerized resources during your (JUnit) tests, e.g. databases or Kafka clusters.

Table of Contents Do We Really Need Plug-ins?

Lately I’ve been fascinated by the possibility to analyse the assembly code emitted by the Java JIT (just-in-time) compiler.

Table of Contents Why JmFrX?

Table of Contents Why Serverless?

Table of Contents Manually Creating CDS Archives Using the CDS Archive Creating CDS Archives in Your Maven Build What Do You Gain?

Table of Contents Format Conversions Ensuring Backwards Compatibility Filtering and Routing Tombstone Handling Externalizing Large Payloads Limitations Learning More Do you remember Angus "Mac" MacGyver?

Table of Contents An Example The Emitter Parameter Pattern For libraries and frameworks it’s a common requirement to make specific aspects customizeable via service provider interfaces (SPIs): contracts to be implemented by the application developer, which

Table of Contents An Example: The Greeter CLI App Application Plug-ins With Layrry Finding Plug-in Implementations With the Java Service Loader Seeing it in Action Making applications extensible with some form of plug-ins is a very common pattern in softw…

Table of Contents Why Layrry?

Table of Contents The Problem The Solution Within Debezium, the project I’m working on at Red Hat, we recently encountered an "interesting" situation where we had to resolve a rather difficult merge conflict.

Table of Contents Custom Flight Recorder Events Creating JFR Recordings Event Settings JFR Event Streaming MicroProfile Metrics Summary and Related Work The JDK Flight Recorder (JFR) is an invaluable tool for gaining deep insights into the performance cha…