java concurrency tutorial

Pk2244-java second kill system scheme optimizes high performance and concurrency combatThe beginning of the new year, learning to be early, drip records, learning is progress!Essay background: In a lot of times, many of the early friends will ask me: I am from other languages transferred to the development of the program, there are some basic information to learn from us, your frame feel too big, I hope to

operation results have not been brushed back to the main memory, resulting in incorrect results, so must be guaranteed order.The nature of the order, then, is to ensure that only one CPU at a time can execute the critical section code. This is usually a lock-up, the nature of the lock is divided into two kinds: pessimistic lock and optimistic lock. such as the typical pessimistic lock synchronized, JUC package under the typical optimistic lock reentrantlock.To sum up: to ensure thread safety, y

more advanced optimization strategy: Each thread allocates a small chunk of memory in the Java heap, called the local thread allocation buffer (Tlab), and the thread internally allocates memory directly on the Tlab. Thread conflicts are avoided. A larger memory space is allocated for CAS operations only when the memory of the buffer needs to be redistributed.If the virtual machine uses Tlab, it can be configured with the-xx:+/-usetlab parameter (Tlab

failed; Nested exception is java.lang.RuntimeException: has been to set current limit times] with root causejava.lang.RuntimeException: already to set current limit times at COM. Souyunku.example.config.LimitAspect.interceptor (limitaspect.java:73) ~[classes/:na] at Sun.reflect.GeneratedMethodAccessor35.invoke (Unknown Source) ~[na:na] at Sun.reflect.DelegatingMethodAccessorImpl.invoke (delegatingmethodaccessorimpl.java:43) ~[na:1.8.0_112] at Java.lang.reflect.Method.invoke (method.java:498) ~[

blocked yo, Should direct output 123 yo, the result pinch? The toilet is blocked!!! Blocked!!! There is no object in the pipeline, can not be taken out, has been waiting for other processes to plug the object in the pipeline, so long as there is a pipeline, it will be blocked. In my example, the first output is 111, and so the main process to plug the object into the pipeline, the Goroutines process will not block, output 123. The conclusion is that the cache channel is not blocked Finally give

The Java.util.concurrent package (J.U.C) after Java5 is the work of the world-class concurrent Master Doug Lea, which mainly implements The corresponding atomic class of Integer/long in atomic package is mainly based on CAS; Some of the same steps, including Lock,countdownlatch,semaphore,futuretask, are based on the Abstractqueuedsynchronizer class; About the executors class of thread execution, etc.; Some concurrent collection classes, such as Concurrenthashmap,concurrentl

Java.util.concurrent.Executor interface for creating a thread pool. The thread pool example shows how to create and use a thread pool, or read the Scheduledthreadpoolexecutor example to learn how to create a periodic task.Java concurrency interview question 1. What is atomic manipulation? What are the atomic classes (atomic classes) in the Java Concurrency API?A

depending on the memory recycling policy), the allocation of space is only the pointer like the free memory side of the object to move the size of the distance.2. Idle list: This applies to memory irregularities, in which case the JVM maintains a memory list that records which memory areas are idle and how large. When assigning space to an object, go to the free list to find the appropriate area and assign it.But the JVM can't always run in a single-threaded state, so inefficient. Because it is

In general development, I often see many students in the Java Concurrent development model will only use some basic methods. Like volatile,synchronized. High-level contracts such as lock and atomic are not often used by many people. I think most of the reasons are due to the nature of the principle. In the busy development work, who will be able to accurately grasp and use the correct concurrency model?So r

Java Concurrency Programming: Concurrenthashmap of Concurrent Containers (reprint)The following part of the content is reproduced from:http://www.haogongju.net/art/2350374New concurrent packages have been added to the JDK5, and concurrent containers have improved concurrency performance through mechanisms relative to the synchronization container. Because the syn