JVM GC Evolution The JVM’s GC algorithms have evolved over the past three decades. The very first GC algorithm shipped with the JVM was the serial collector. Initially, Java was popular on the client side (Java Applets), and the serial collector was perfect for its GC needs. However, the serial collector worked well only on small […]
Archive | JVM
Understanding JVM Garbage Collection – Part 4
JVM GC Terminology The terminology used to describe garbage collection algorithms can be confusing. In this section, we will explain some commonly used terms and their meanings. Live set – The live set refers to the number of live objects in a heap. The size of the live set has a significant impact on the […]
Understanding JVM Garbage Collection – Part 3
Weak Generational Hypothesis The weak generational hypothesis has had a profound impact on the JVM’s heaps layout. Understanding the weak generational hypothesis is essential in order to understand various GC algorithms and approaches. The Weak Generational Hypothesis states that most objects die young. In other words, most objects created will be garbage collected very quickly. […]
Understanding JVM Garbage Collection – Part 2
GC Mark, Sweep, and Compact Basics The Mark and Sweep algorithm is the basis for garbage collection in Java. Although the actual algorithms used by the JVM are considerably more complex, the mark and sweep algorithm forms the basis of garbage collection in the JVM and must be understood. As you might have guessed, there […]
Understanding JVM Garbage Collection – Part 1
Java is a popular language for business and enterprise computing. Java and the JVM have enjoyed enormous success over the last two decades. Java was initially considered a slow language (late 90’s). That changed with the introduction of the HotSpot virtual machine in April 99. HotSpot improved performance via “just in time” compilation and adaptive optimisation. Since […]