jvm memory management

Memory, as an important resource in the system, plays a key role in the stable operation and efficient operation of the system, unlike languages like Java and C, which do not require the developer to allocate memory and reclaim memory, but rather the JVM manages the allocation of object

the returnadress type (the address of the next bytecode Directive). The memory space required for the local variable table is allocated during compilation, and the local variable table requires a fixed amount of memory before the method is run and does not change during the run time.Stack frame is a memory block, is a data set, is a method and run-time data set

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 creat

A deep understanding of one jvm [memory region] and a deep understanding of the jvm Region Before the beginning of this article, we need to declare that this series of articles discuss the hot spot VM. Most of the ideas in this article are based on Zhou Zhiming, who deeply understands the Java VM: JVM advanced features

In this section we summarize the memory allocation policy in the JVM. The directory is as follows: Memory allocation policyObject first in New Generation Eden AssignmentLarge objects go straight into the old ageLong-lived objects will enter the old age.Dynamic Object Age DeterminationSpace allocation guaranteed memory

Deep understanding of JVM (1)-Java memory region, jvm-java 1. Data Area During Running During Java program execution, the Java Virtual Machine divides the memory it manages into several different data regions. The memory managed by the Java Virtual Machine will include the f

Chapter 2 JVM memory allocation and Chapter 2 jvm allocation Note: This blog is mainly based on the following three books: Distributed Java applications: basics and practices Deep understanding of Java Virtual Machine (version 2) 16 lessons that break the basic skills of programmers Note: For details about the JVM

Transferred from: http://www.javatang.com/archives/2007/12/03/1653250.htmlIf not set, the use of myeclipse often appears as shown in insufficient memory hints.The hint says very clearly: "MyEclipse has detected that less than 5% of the 64MB of Perm Gen (non-heap memory) space remains." This means that only less than 5% of the non-heap memory is currently idle. So

Learn JVM easily (II)-memory model, visibility, Command Re-sorting, jvm Model In the previous article, we introduced the basic running process and memory structure of JVM, and had a preliminary understanding of JVM, in this articl

System CentOS6.4 Yum installed Tomcat6 and jdk1.6, the installation configuration process is as follows: Http://www.111cn.net/sys/CentOS/72007.htm The deployment of two projects A and B in Tomcat, as well as the time of memory overflow error in the deployment times, the system CPU load is soaring, and a, B, and only multiple a, or just multiple B-project systems are deployed separately for normal operation. View Log error: Outofmemoryerror:permgen

Memory Allocation for various data types in jvm, and jvm allocation for Data TypesJvm runtime data zone: the memory managed by JVM is divided into the following runtime data zones: Program counters, Java Virtual Machine stacks, local method stacks, Java stacks, and method zo

JVM Memory Model The memory space of the Java Virtual machine (Java MACHINE=JVM) is divided into five parts, respectively:1. Program counter2. Java Virtual machine stack3. Local Method Stack4. Heap5. Method area. The following is an in-depth introduction to these five regions.1. Program Counter 1.1. What is a program c

access objects on the heap? (1) Direct access to the pointer The reference on the stack holds the pointer to the object on the heap, and the object can be positioned at once, and the access is faster.But when the object is moved in the heap (the objects are often moved when garbage collection), the value of the pointer variable on the stackAlso need to change. This is the way the JVM hotspot is currently used. (2) Handle indirect access The ref

JVM-concurrency-Java memory model, jvm-concurrency-java modelJava Memory Model (1). Master memory and working memory The Java Memory Model specifies that all variables are stored in the

(Eden) in the Young Generation (bytes)EU: Eden (Eden) in the young generation has currently used space (bytes)capacity of the Oc:old generation (bytes)Ou:old currently used space (bytes)pc:perm (persistent generation) capacity (bytes)pu:perm (persistent generation) currently used space (bytes)YGC: Number of GC times in young generations from application startup to samplingYGCT: The time taken by the GC in the young generation from application startup to sampling (s)FGC: Old (full GC) GC count f

This section Xiao Wang focuses on the next Java memory, first ask: How 1.JVM memory is allocated 2. Why divide the new generation and the old age, in practice which belong to what belongs to the old 3. Briefly describe how JSTAT-GC How 1.JVM memory is allocated 1.1 Concept I

JVM memory structure --- deep understanding of Java Virtual Machine (jvm) When executing a Java program, the Java Virtual Machine divides the memory it manages into several different data regions. These regions have different purposes and create and destroy data independently based on their respective execution rules.

Jvm memory growth troubleshooting examples and jvm troubleshooting examplesTroubleshoot jvm memory Growth Troubleshoot the problem that the jvm memory usage continues to increase. recor

functions. Unused extents are prestaged areas that allocate new memory space.Second, process and JVM memory modelThe JVM is essentially a process, so its memory model also has the general characteristics of the process. However, the JVM