Programmer Think

In Go language, there are not only easy-to-use and advanced synchronization mechanisms such as channel, but also sync Mutex ,sync.WaitGroup and others compare the original synchronization mechanism. Through them, we can more flexibly control data synchronization and multi process concurrency. Resource competition In a goroutine, if the alloca ...

What is a blocking queue? A linear structure, FIFO first in first out, can be operated at both ends, adding one side and deleting the otherSupport blocking insertion and blocking removal (for example, the production consumer mode demonstrated in the previous chapter)The list size is divided into bounded queue and unbounded queue. Unbounded que ...

Essence: locks are used to solve thread safety problems Other implementations of Lock in Java, such as WiteLock write Lock and ReadLock read Lock, are mainly expanded with ReentrantLock reentry Lock in this paper ReentrantLock reentrant lock Reentry lock and mutex lock are used to solve the deadlock problem 1. Use of reentrantlock static L ...

Thread synchronization Basics In concurrent scenarios, sometimes we don't just want to protect data. We also want to synchronize some operations between multiple threads, such as waiting for a condition to be true or executing some operations when an event occurs. The C + + standard library provides condition variables and futures; Concurrency ...

1. AQS The full name is AbstractQueuedSynchronizer, which is the framework for blocking locks and related synchronizer tools. It is characterized by the state attribute representing the state of the resource (exclusive and shared), and subclasses that define how to maintain this state and control how locks are acquired and released. 1. getState ...

Start with SimpleDateFormat Let's first look at an example. When 20 threads are created, one thing is done in the thread, that is, the conversion time public class ThreadLoaclExample { //Non thread safe private static final SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); public static Date parse(String strDat ...

ReentrantLock is implemented based on AQS (AbstractQueuedSynchronizer). It is divided into fair lock and unfair lock. ReentrantLock can be set as a fair lock by entering and leaving true in the constructor. AQS is a FIFO two-way queue, which internally records the queue head and tail elements through nodes head and tail. The type of queue elem ...

JUC concurrent programming -- understanding of various locks 1. Fair lock Fair lock means that when the lock is available, the thread waiting on the lock for the longest time will obtain the right to use the lock and must come first. //ReentrantLock(true) is set to fair lock public ReentrantLock(boolean fair) { sync = fair ? new Fair ...

11. Mutex initiate static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;      The memory unit is not released until the process is completed dynamic initialization pthread_mutex_t mutex; // Define mutex objects pthread_ mutex_ init(&mutex, NULL); // Allocate kernel resources ... pthread_ mutex_ destroy(&mutex); // F ...