Enhanced JEP 376: ZGC on Windows

JEP 376: ZGC on Windows is an enhancement introduced in Java 17 that extends the support for Z Garbage Collector (ZGC) to the Windows platform. Prior to this enhancement, ZGC was available only on Linux and macOS. This update allows Java applications running on Windows to take advantage of the low-latency, scalable features of ZGC, which is particularly beneficial for applications that require high performance and low pause times.

What is ZGC?

ZGC (Z Garbage Collector) is a low-latency garbage collector introduced in Java 11. It is designed to minimize the pause times during garbage collection (GC) by performing most of the work concurrently, in parallel, and in small increments. This makes ZGC ideal for applications that need to maintain high responsiveness, such as real-time systems, large-scale applications, and microservices architectures.

Key Features of ZGC

1. Low Pause Times:

   • ZGC is designed to keep pause times below 10ms, even in large heaps. It achieves this by using techniques such as concurrent marking, concurrent relocation, and parallel reference processing.

2. Scalability:

   • ZGC can scale to large heaps, making it suitable for workloads that require large amounts of memory (up to multi-terabyte heaps). It supports applications with large memory footprints without significant performance degradation during GC.

3. Concurrent Garbage Collection:

   • The majority of the garbage collection phases in ZGC run concurrently with the application, reducing interruptions and ensuring that the application remains responsive.

What Changed with JEP 376?

Before Java 17, ZGC was only available on Linux and macOS. JEP 376 added support for Windows (specifically, Windows x64), making it available to a broader range of Java developers and organizations who run Java applications on Windows platforms.

Key Benefits of JEP 376

1. Cross-Platform Consistency:

   • With ZGC now available on Windows, developers can write cross-platform applications that take advantage of ZGC’s benefits, regardless of whether they are running on Linux, macOS, or Windows.

2. Improved Performance for Windows Applications:

   • Windows developers can now leverage the low-latency and scalability features of ZGC for applications that require minimal pause times, making ZGC a viable option for high-performance applications on Windows.

3. Enhanced Garbage Collection:

   • ZGC improves the garbage collection process by allowing more concurrent operations, which reduces the impact of GC on application performance. This is particularly useful for memory-intensive applications.

4. Better Memory Management:

   • Windows developers can use ZGC to handle large heap sizes efficiently, enabling better memory management for applications that require significant amounts of memory.

Use Cases for ZGC

1. Real-Time Applications:

   • Applications that need to maintain low latency, such as trading systems, gaming servers, and real-time data processing applications, can benefit from ZGC’s low-pause-time nature.

2. Large-Scale Applications:

   • Applications with large memory footprints (e.g., data analytics, AI/ML systems) can use ZGC to manage memory more efficiently, minimizing the pauses that can occur during traditional garbage collection.

3. Cloud and Microservices:

   • ZGC is also suitable for cloud applications and microservices that need to scale efficiently while maintaining low latency across distributed systems.

How to Enable ZGC on Windows

To enable ZGC in Java 17 on Windows, developers can use the following JVM option when starting a Java application:

java -XX:+UseZGC -jar your-application.jarCode language: CSS (css)