Shulou(Shulou.com)06/02 Report--

This article mainly introduces "how Go uses sync.Map to solve the problem of concurrent operation of map". In daily operation, I believe that many people have doubts about how Go uses sync.Map to solve the problem of concurrent operation of map. Xiaobian consulted all kinds of materials and sorted out simple and easy-to-use operation methods. I hope it will be helpful to answer the doubt of "how Go uses sync.Map to solve the problem of concurrent operation of map". Next, please follow the editor to study!

Preface

In Golang, map is not concurrency secure. Sync.Map has only been introduced since 1.9. the introduction of sync.Map does solve the concurrency security problem of map, but sync.Map does not implement the len () function. If you want to calculate the length of sync.Map, it is a little troublesome to use the Range function.

There is a problem with map concurrent operation

Func main () {demo: = make (int) go func () {for j: = 0; j < 1000; go func + {for [j] = j} () go func () {for j: = 0; j < 1000; time.Sleep () time.Sleep (time.Second * 1)}

Perform output:

Fatal error: concurrent map read and map write

Sync.Map solves the problem of concurrent operation

Func main () {demo: = sync.Map {} go func () {for j: = 0; j < 1000; go func + {for (j, j)} () go func () {fmt.Println (demo.Load (j))} () time.Sleep (time.Second * 1)}

Perform output:

False

1 true

...

999 true

Calculate map length

Func main () {demo: = make (map [int] int) for j: = 0; j < 1000; fmt.Println + {demo [j] = j} fmt.Println ("len of demo:", len (demo))}

Perform output:

Len of demo: 1000

Calculate sync.Map length

Func main () {demo: = sync.Map {} for j: = 0; j < 1000; lens + {demo.Store (j, j)} lens: = 0 demo.Range (func (key, value interface {}) bool {lens++ return true}) fmt.Println ("len of demo:", lens)}

Perform output:

Len of demo: 1000

At this point, the study on "how Go uses sync.Map to solve the problem of concurrent operation of map" is over. I hope to be able to solve everyone's doubts. The collocation of theory and practice can better help you learn, go and try it! If you want to continue to learn more related knowledge, please continue to follow the website, the editor will continue to work hard to bring you more practical articles!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.