Java 15 - Garbage Collectors

Java 15 has made the ZGC, Z Garbage Collector a standard feature. It was an experimental feature till Java 15. It is low latency, highly scalable garbage collector.

ZGC was introduced in Java 11 as an experimental feature as developer community felt it to be too large to be released early. A lot of improvements are done to this garbage collection since then, for example −

Concurrent class unloading

Uncommiting of unused memory

Support for Class Data Sharing

NUMA Awareness

Multithreaded Heap Pre-touch

Max Heap Size pmit from 4 TB to 16 TB.

ZGC is highly performant and works efficiently even in case of massive data apppcations e.g. machine learning apppcations. It ensures that there is no long pause while processing the data due to garbage collection. It supports Linux, Windows and MacOS.

The Shenandoah low-pause-time garbage collector is now out of the experimental stage. It had been introduced into JDK 12 and from java 15 onwards, it is a part of standard JDK.