Home Java javaTutorial What is the java heap?

What is the java heap?

Dec 26, 2019 pm 03:52 PM
java heap

What is the java heap?

For most applications, the Java Heap (Java Heap) is the largest piece of memory managed by the Java virtual machine. The Java heap is a memory area shared by all threads and is created when the virtual machine starts. The only purpose of this memory area is to store object instances, and almost all object instances allocate memory here. This is described in the Java virtual machine specification as follows: All object instances and arrays must allocate memory on the pair. However, with the development of JIT compilers and the gradual maturity of escape analysis technology, on-stack allocation and scalar replacement optimization technologies will This will lead to some subtle changes, and all objects allocated on the heap will gradually become less "absolute".

The Java heap is the main area managed by the garbage collector, so it is often called the "GC heap" (Garbage Collected heap). From the perspective of memory recycling, since current collectors basically use generational collection algorithms, the Java heap can also be subdivided into: new generation and old generation; in more detail, there are Eden space, From Survivor space, To Survivor space space etc. From the perspective of memory allocation, the thread-shared Java heap may be divided into multiple thread-private allocation buffers. However, no matter how divided it is, it has nothing to do with the stored content. No matter which area, object instances are still stored. The purpose of further dividing is to better recycle memory or allocate memory faster.

According to the Java Virtual Machine Specification, the Java heap can be in physically discontinuous memory space, as long as it is logically continuous, just like our disk space. During implementation, it can be either fixed size or expandable, but currently mainstream virtual machines are all implemented as scalable. If there is no memory in the heap to complete the instance allocation and the heap cannot be expanded, an OutOfMemoryError exception will be thrown.

Summary

1. The java heap is the largest piece of memory managed by the java virtual machine

2. The java heap is used by all threads Shared

3. The main function of the java heap is to store object instances

4. The ava heap is the main area managed by the garbage collector

5. The collector basically uses Generational collection algorithm

6. The Java heap can be divided into the new generation and the old generation. More detailed, it can also be divided into Eden area, From Surivor area, and To Surivor area

Recommended learning: JavaVideoTutorial

The above is the detailed content of What is the java heap?. For more information, please follow other related articles on the PHP Chinese website!

Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

AI Hentai Generator

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
2 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
Repo: How To Revive Teammates
4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
Hello Kitty Island Adventure: How To Get Giant Seeds
4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Square Root in Java Square Root in Java Aug 30, 2024 pm 04:26 PM

Guide to Square Root in Java. Here we discuss how Square Root works in Java with example and its code implementation respectively.

Perfect Number in Java Perfect Number in Java Aug 30, 2024 pm 04:28 PM

Guide to Perfect Number in Java. Here we discuss the Definition, How to check Perfect number in Java?, examples with code implementation.

Random Number Generator in Java Random Number Generator in Java Aug 30, 2024 pm 04:27 PM

Guide to Random Number Generator in Java. Here we discuss Functions in Java with examples and two different Generators with ther examples.

Weka in Java Weka in Java Aug 30, 2024 pm 04:28 PM

Guide to Weka in Java. Here we discuss the Introduction, how to use weka java, the type of platform, and advantages with examples.

Armstrong Number in Java Armstrong Number in Java Aug 30, 2024 pm 04:26 PM

Guide to the Armstrong Number in Java. Here we discuss an introduction to Armstrong's number in java along with some of the code.

Smith Number in Java Smith Number in Java Aug 30, 2024 pm 04:28 PM

Guide to Smith Number in Java. Here we discuss the Definition, How to check smith number in Java? example with code implementation.

Java Spring Interview Questions Java Spring Interview Questions Aug 30, 2024 pm 04:29 PM

In this article, we have kept the most asked Java Spring Interview Questions with their detailed answers. So that you can crack the interview.

Break or return from Java 8 stream forEach? Break or return from Java 8 stream forEach? Feb 07, 2025 pm 12:09 PM

Java 8 introduces the Stream API, providing a powerful and expressive way to process data collections. However, a common question when using Stream is: How to break or return from a forEach operation? Traditional loops allow for early interruption or return, but Stream's forEach method does not directly support this method. This article will explain the reasons and explore alternative methods for implementing premature termination in Stream processing systems. Further reading: Java Stream API improvements Understand Stream forEach The forEach method is a terminal operation that performs one operation on each element in the Stream. Its design intention is

See all articles