Golang-goroutine互斥锁与读写互斥锁

package main

// go build -race main.go 编译后运行查看

import (
	"fmt"
	"sync"
	"time"
)

var wg sync.WaitGroup
var mutex sync.Mutex

var m = make(map[int]int, 0)

func test(num int) {
	mutex.Lock()
	var sum = 1
	for i := 1; i <= num; i++ {
		sum *= i
	}
	m[num] = sum
	fmt.Printf("key=%v value=%v\n", num, sum)
	time.Sleep(time.Millisecond)
	mutex.Unlock()
	wg.Done()

}

func main() {
	for r := 0; r < 40; r++ {
		wg.Add(1)
		go test(r)
	}
	wg.Wait()
}

package main

// go build -race main.go 编译后运行查看

import (
	"fmt"
	"sync"
	"time"
)

var wg sync.WaitGroup
var mutex sync.RWMutex

func read() {
	mutex.RLock()
	fmt.Println("---执行读操作---")
	time.Sleep(time.Second * 2)
	mutex.RUnlock()
	wg.Done()
}

func write() {
	mutex.Lock()
	fmt.Println("执行写操作")
	time.Sleep(time.Second * 2)
	mutex.Unlock()
	wg.Done()

}

func main() {
	// 开启10个协程执行读操作
	for i := 0; i < 40; i++ {
		wg.Add(1)
		go read()
	}
	// 开启10个协程执行写操作
	for i := 0; i < 10; i++ {
		wg.Add(1)
		go write()
	}
	wg.Wait()
}