lock用来解决多协程对共享资源进行竞争
优点:比较灵活，可以针对代码段加锁
package main
import (
"fmt"
"sync"
)
// lock用来解决多协程对共享资源进行竞争
var total int32
var wg sync.WaitGroup
var lock sync.Mutex
func add() {
defer wg.Done()
for i := 0; i < 10000; i++ {
lock.Lock()
total += 1
lock.Unlock()
}
}
func dec() {
defer wg.Done()
for i := 0; i < 10000; i++ {
lock.Lock()
total -= 1
lock.Unlock()
}
}
func main() {
wg.Add(2)
go add()
go dec()
wg.Wait()
fmt.Printf("done all total %d\n", total)
}
//--- done all total 0
用go内置的原子操作函数来实现
package main
import (
"fmt"
"sync"
"sync/atomic"
)
// lock用来解决多协程对共享资源进行竞争
var total int32
var wg sync.WaitGroup
// var lock sync.Mutex
func add() {
defer wg.Done()
for i := 0; i < 10000; i++ {
//lock.Lock()
//total += 1
//lock.Unlock()
// 直接使用原子操作
atomic.AddInt32(&total, 1)
}
}
func dec() {
defer wg.Done()
for i := 0; i < 10000; i++ {
//lock.Lock()
//total -= 1
//lock.Unlock()
atomic.AddInt32(&total, -1)
}
}
func main() {
wg.Add(2)
go add()
go dec()
wg.Wait()
fmt.Printf("done all total %d\n", total)
}
//--- done all total 0