Go RWMutex 读写锁

RWMutex

可并行读，读写互斥。有写时，所有读都暂停。

类似于Java中的ReentrantReadWriteLock。

代码

var rwMutex sync.RWMutex

func main() {
    amount := 0
    for i := 0; i < 10; i++ {
        go Read(&amount)
    }
    for i := 0; i < 10; i++ {
        go Write(&amount)
    }

    time.Sleep(time.Second * 3)

    Read(&amount)
}

func Read(amount *int) {
    rwMutex.RLock()
    defer rwMutex.RUnlock()
    println(time.Now().String(), "#", *amount)
}

func Write(amount *int) {
    rwMutex.Lock()
    defer rwMutex.Unlock()
    *amount += 1
}

读锁

RLock上读锁，RUnlock解除读锁。

func Read(amount *int) {
    rwMutex.RLock()
    defer rwMutex.RUnlock()
    println(time.Now().String(), "#", *amount)
}

写锁

Lock上写锁，Unlock解除写锁。

func Write(amount *int) {
    rwMutex.Lock()
    defer rwMutex.Unlock()
    *amount += 1
}