cas operation

CAS is a modern operating system, to solve the problem of concurrency is an important means, recently in the Eureka to see the source code. Many CAS operations were encountered. Today we will review the CAs in Java in a systematic way. Read this

Atomicinteger SourceUnder the Java.util.concurrent.atomic package provides a large number of atomic classes, here to Atomicinteger source code for example, added some comments, personal understanding, for reference;One of the more important concepts

This article says that the class in the java.util.concurrent.atomic bag, a total of 12. There are very many articles on the Web parsing these classes. Here are some key points to talk about.These 12 classes can be divided into three groups:1. Common

ObjectiveEfficient concurrency is what programmers always pursue when they write code, and the Hotspot virtual machine development team has done a lot of work to share data more efficiently between threads, and to solve competition issues, The

First, the weight of class lockIn the previous article, we introduced the usage of synchronized and the principle of its realization. Now we should know that synchronized is implemented by a monitor lock inside the object. But the nature of the

1. PrefaceThe previous article recorded the relationship between Java's memory model and thread, which has been addressed by the memory model to the problem of thread safety. This article will be a specific description of thread safety, the

Talking about high concurrency (v.) Understanding of Cache consistency protocol and its impact on concurrent programming we understand the principle of the processor cache consistency protocol, it also refers to its impact on concurrent programming,

Java Concurrent Programming Series "Not finished": Java concurrency Programming: core theory Java Concurrency Programming: synchronized and its implementation principles Java concurrency Programming: Synchronized bottom-level

An atomic operation is an operation that cannot be interrupted during the process. Atomic operation for a value in the process of being carried out, the CPU will never go to another operation for that value.To achieve this rigor, atomic operations

The lock-free programming is really fascinating and hateful. The blogger has previously written several articles about lock-free programming. For example, about lockless programming and concurrent data structures: Fascinating atoms. For more

Under the influence of the core idea of CLH lock, the basic framework of Java and contract Aqs is designed based on CLH Lock, which is mainly considering that the CLH lock is easier to implement cancellation and timeout function. Compared to the

Summarize: The atomic package provides four types of atomic classes. Includes four types of basic data types, arrays, reference types, and reference type member variables. The lower level uses CAS operations to ensure atomicity, and CAS

In many cases we just need a simple, efficient, thread-safe increment-decrement scheme. Note that there are three conditions: simple, which means that it is easier for programmers to operate the underlying or implement as little as possible, and

Prior to JDK 5, the Java language was guaranteed to be synchronized by the Synchronized keyword, which would result in a lock (later chapters will also talk about locks).The lock mechanism has the following issues:(1) Under the multi-thread

IntroductionAs we said in the previous article, volatile is guaranteed visibility, ordering, and "partial" atomicity through the lock command. However, in most concurrency problems, it is necessary to ensure the atomicity of the operation, volatile

First, start with the atomic operationStart with a relatively simple atomic (Java.util.concurrent is a queue-based contract and the queue, in many cases, uses the atomic operation, so begin here first).In many cases we just need a simple, efficient,

The problem of CAs operation is mentioned, that is, before CAs a becomes B and a,cas or can be set successfully, what scenario will appear this problem? Looked up some information, found that in the following two cases of ABA problems will occur.1.A

Synchronized Favorites Summary In the CAS principle Java SE1.6: Synchronized is always the oldest role in multithreaded concurrent programming, and many people call it a heavyweight lock, but as Java SE1.6 has optimized synchronized, and in some

From: http://www.blogjava.net/xylz/archive/2010/07/07/325410.html Next, this article starts with lock. Lock/unlock. In special cases, all programs, APIs, and documents are based on JDK 6.0. Public void java. util. Concurrent. locks. reentrantlock.

In the process of learning or using Java, the process encounters a variety of lock concepts: Fair lock, unfair lock, spin lock, reentrant lock, biased lock, lightweight lock, heavyweight lock, read-write lock, mutex wait. Here to tidy up the various