jvm architecture

As we all know, the JVM used to be interpreted in the past, but later in the history of the revision also added to the implementation of the compilation. So in general the JVM is comprised of interpretation execution and compilation execution. This part does not belong to the scope of the JVM, has been compiled, most of them are lexical analysis and the like, the

The JVM is a virtual machine and a specification, and he follows the design principles of the von Neumann architecture. Von Neumann architecture, it is pointed out that the computer processing data and instructions are binary number, using stored procedures to store in the same memory without distinction, and sequential execution, instruction by the operation cod

collection. The difference from ParNew is that it has different concerns and can precisely control the throughput. [Throughput = program running time/(program running time + garbage collection time). For example, the JVM runs for 100 minutes. The garbage collection takes 1 minute, And the throughput is 99%: Parallel Scavenge Parallel collection 4,Serial Old (Serial collector): It is an old version of the Serial collector. It uses the tag-compressio

used. Mark-Compact) The Mark compression algorithm is a collection algorithm in the old age. The markup phase is consistent with the markup clearing algorithm, marking reachable objects once. In the cleaning phase, all surviving objects are compressed to one end of the memory to avoid Memory fragments. Garbage Collector The garbage collector is the specific implementation of memory recycling. The garbage collectors provided by different vendors are very different. Generally, the garba

[JVM] template interpreter-how to generate Assembly codes based on bytecode ?, Jvm Interpreter 1. Background Template interpreter for JVM only: How to generate an assembly code based on the opcode and addressing mode. For the bytecode and sink encoding used in this example, see the previous blog post: pass by value or by reference? 2. Addressing Mode This art

JVM re-sorting and JVM re-sorting Reordering is usually a method used by the compiler or runtime environment to re-sort and execute commands to optimize program performance. There are two types of re-sorting: Re-sorting during compilation and re-sorting during runtime, which correspond to the compiling and runtime environments respectively. In a concurrent program, the programmer pays special attention to d

attention to the bottom of the implementation, the novice programmer as long as familiar with the basic use of methods, you can quickly develop on-line; but for senior programmers, the practice of internal strength is more important , such as algorithms, design patterns, underlying principles, and so on, only after these basic proficiency, in the development process can know its why, when problems can quickly locate the nature of the Problem.For Java programmers, Spring family barrels can almos

JVM-Concepts and jvm-Experiences I recently took the time to review the JVM concept. Now I will record my experiences. Part 1: abstract a JVM concept diagram based on learning to describe the composition and basic functions of each major component. Part 2: Describe the content based on the structure diagram. 1) --

Brief introduction Starting with IBM I 7.1, IBM Classic Java Virtual Machine is no longer supported by IBM I. The IBM Technology for Java Virtual Machine (also known as the IBM J9 JVM) became the only supported JVM. This article is intended to illustrate the differences between the two JVMs, while helping users and developers migrate their applications from the Classic

JVM adjusts the memory scale appropriately (provided that the proportional-based Yong and settings are used). -XX:+USECONCMARKSWEEPGC launches a concurrent GC, typically for the tenured zone. The -xx:+cmsincrementalmode increments the GC, cutting the memory in chunks and distributing it across multiple partial GC. - xx:cmsinitiatingoccupancyfraction under concurrent GC, because one side is used, once the GC is not enough, the GC

Preface 32-bit and 64-bit systems are often mentioned in the computer field, but many people do not know the difference between 32-bit and 64-bit systems. Therefore, I have compiled some documents online, I hope to share with you. For 32-bit and 64-bit, this article will explain from the processor, operating system, and JVM respectively. IA Introduction Introduction Speaking of processors, most people use Intel's processors. Therefore, this article ma

JVM monitoring tools-Introduction to several common tools and jvm monitoring-common toolsIntroduction to JVM monitoring tools Jdk provides a powerful GUI-based jvm monitoring tool, which can be seen in the jdk bin directory, such as jconsole, jvisualvm, and oracle jrockit jvm's jrmc.exe.Introduction: GUI tools

JVM Memory Model and jvm Model JVM defines the data regions used during execution of several programs. Some data in this region is created at JVM startup and destroyed at JVM exit. Other data depends on every thread. It is created when the thread is created and destroyed w

This article says how to understand threads from a JVM's point of view, you can have a deeper understanding of the Java threading model, and some of the details of the GC will be more deeply understood. This paper is based on the OpenJDK7 implementation of hotspot.We know that the JVM is primarily implemented in C + +, and the class inheritance structure for the thread defined by the JVM is as follows:Class

JVM garbage collection mechanism and jvm garbage collection Scope: areas to be recycled Among the five JVM memory models, three do not require garbage collection: Program counters, JVM stacks, and local method stacks. Because their lifecycle is synchronized with the thread, the memory they occupy will be automatica

A better-performing Web server JVM parameter configuration:-server//Server Mode-xmx2g//JVM the maximum allowable allocated heap memory, on demand-xms2g//JVM the initial allocated heap memory, generally and xmx configured to avoid the JVM reallocating memory after each GC. -xmn256m//Young generation memory size, entire

Overview of JVM knowledge points-required for interviews with senior and middle-level Java engineers, and jvm Overview The same is true for developers. There are more and more popular frameworks and more comprehensive packages. Various frameworks can handle everything, and there is almost no need to focus on the underlying implementation, as long as junior programmers are familiar with basic usage methods,

How JVM works, how jvm works I. JVM Lifecycle The life cycle of a Java VM is a clear task for executing Java programs. It runs only when the program starts to run, and stops when the program ends. When you run three programs on the same machine, there will be three running Java virtual machines. The Java Virtual Machine always starts with a main () method. This m

Whether it is YGC or full gc,gc in the process of causing the program to break, the correct choice of different GC policies, tuning the JVM, GC parameters, can greatly reduce the problem caused by the work of the GC, resulting in the operation of the program to improve the efficiency of the Java program. However, the tuning of GC is a very complex process, due to different features of the program, such as: Web and GUI programs have a very big differen

JVM exploration-Memory Management (1), jvm exploration Memory Management The first article in this series is expected to have two or three cases at the end of this series. Java is different from C and C ++. Java does not need Coder for manual memory management, and all of this is handed over to JVM for automatic memory management, to some extent, this reduces th