passageway
1. When a resource needs to be shared between goroutines, the channel sets up a pipeline between goroutines
2. No buffer channel and buffered channel. The second parameter of make is buffer size
3. The bufferless channel needs to be ready for sending and receiving, otherwise the goroutine executed first will block waiting
4. For the buffered channel, before the buffer is full, the transmit and receive actions will not block, and only when the buffer is empty will the receive block
time.Now().Unix() current time stamp time.milliseconds
time.Sleep(1 * time.Second) sleep for one second
package main import ( "fmt" "math/rand" "sync" "time" ) const ( //Global constant numberGoroutines = 4 //Number of goroutine used taskLoad = 10 //Workload to be handled ) var wg sync.WaitGroup //init function will execute before main func init() { //Initialize random number rand.Seed(time.Now().Unix()) } func main() { //Create buffered channel management, buffer is 10 tasks := make(chan string, taskLoad) //Start 4 goroutines to handle the work wg.Add(numberGoroutines) //Add count semaphore for i := 1; i <= numberGoroutines; i++ { go worker(tasks, i) } //The main goroutine sends 10 strings to the channel, simulating the work of distributing to the sub goroutine for j := 1; j <= taskLoad; j++ { tasks <- fmt.Sprintf("Task: %d", j) } //After sending, close the channel close(tasks) //If you plug the channel all the way, the sub goroutine can work all the time and can be used as a queue // for { // tasks <- fmt.Sprintf("Task: %d", rand.Int63n(10000000000)) // } //Wait for all goroutines to finish wg.Wait() } //Processing work func worker(tasks chan string, worker int) { defer wg.Done() //Infinite loop processing the received work, you can continue to process the next work after finishing one for { //From the closed channels, data can still be received and a channel type zero value is returned. If none is received, it will block //After receiving one, it will continue to execute task, ok := <-tasks //Judge whether the channel is empty and closed if !ok { fmt.Printf("Worker: %d:Close\n", worker) //Get out of this goroutine return } //Start work formally fmt.Printf("Worker: %d:Start-up\n", worker) //Simulating execution with random sleep sleep := rand.Int63n(100) time.Sleep(time.Duration(sleep) * time.Millisecond) //Display completed fmt.Printf("Worker: %d :complete %s \n", worker, task) } }
