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Class Loading Class Loading Phase Load Loading the byte code of a class into the method area (metaspace after 1.8, in local memory) describes the java class internally with instanceKlass in C++. Its important fi eld s are: _ java_mirror is a class mirror of java. For String, for example, its mirror class is String.class, the purpose is to e ...

1, Alibaba Arthas details Arthas is a Java diagnostic tool open source by Alibaba in September 2018. JDK6 + is supported, and the command line interaction mode is adopted, which can easily locate and diagnose online program operation problems. The official documents of Arthas are very detailed. See: https://alibaba.github.io/arthas Arth ...

Summary of 8 cases of memory leakage in java Since the java JVM introduces the garbage collection mechanism, the garbage collector will automatically collect objects that are no longer used. Those who understand the JVM collection mechanism know that the JVM uses the reference counting method and reachability analysis algorithm to judge whethe ...

A finishing touch The JVM supports two types of class loaders: Bootstrap ClassLoader and User-Defined ClassLoader. Conceptually, a custom class loader generally refers to a class loader defined by developers in a program, but the Java virtual machine specification does not define it. Instead, all class loaders derived from the abstract class ...

catalogue 1, Overview 2, Process 1: Loading stage 3, Summary 1, Overview In Java, data types are divided into basic data types and reference data types. The basic data type is pre-defined by the virtual machine, and the reference data type needs to be loaded. According to the Java virtual machine specification, from the class file to the ...

Preface Preface To better consolidate and comb JVM knowledge, write this article. Prepare for the fall enrollment. Most of this knowledge comes from Understanding JAVA Virtual Machines. Interested people can read it by themselves~! There is also some content from the B-Station decryption JVM [Produced by the Black Horse Programmer] teac ...

1. Introduction          MAT (Memory Analyzer Tool) is a powerful Java heap memory analyzer. It can be used to find memory leaks and view memory consumption. MAT is developed based on Eclipse. It can not only be used alone, but also be embedded in Eclipse as a plug-in. It is a free performance analysi ...

1. Background introduction 1.1 introduction to application background 1) Business features: the traffic peak is concentrated in the daytime, and the traffic is very low in the early morning. 2) Application features: Many core business interfaces are provided externally. After 6 a.m., the traffic increases gradually.In the early morning, we ...

This article is compiled and published by jiumo (Ma Zhi), chief lecturer of HeapDump performance community Part 29 - calling the main() method of the Java main class Many articles have been written to introduce the assembly code execution logic corresponding to bytecode instructions, and some assembly code logic corresponding to bytecode instr ...

java class loading mechanism What is class loading? Class loading refers to reading the binary data in the class's. Class file into memory, placing it in the method area of the runtime data area, and then creating a java.lang.Class object in the heap area [that is, the class object we use in mapping] to encapsulate the data structure of the cla ...