Go实现生产者消费者模型

雨点打透心脏的1/2处 2022-10-06 00:39 194阅读 0赞

# Go实现生产者消费者模型 #

## 基于同步锁实现 ##

import (
    	"fmt"
    	"sync"
    )
    var (
    	productCount = 5
    	mutex sync.Mutex
    	cond = sync.NewCond(&mutex)
    )
    type producer struct { 
    
    }
    func (r *producer) produce() { 
    	for { 
    		cond.L.Lock()
    		if productCount < 10 { 
    			productCount++
    			fmt.Printf("生产者生产了一个产品，当前存量%d\n", productCount)
    		} else { 
    			fmt.Printf("仓库满了，当前容量%d\n", productCount)
    			cond.Wait()
    		}
    		cond.L.Unlock()
    		cond.Broadcast()
    	}
    }
    func (r *consumer) consumer() { 
    	for { 
    		cond.L.Lock()
    		if productCount > 0 { 
    			productCount--
    			fmt.Printf("消费者消费了一个产品，当前存量%d\n", productCount)
    		} else { 
    			fmt.Printf("仓库空了，当前存量%d\n", productCount)
    			cond.Wait()
    		}
    		cond.L.Unlock()
    		cond.Broadcast()
    	}
    }
    type consumer struct { 
    
    }
    func main() { 
    	var p = producer{ }
    	var c = consumer{ }
    	go p.produce()
    	go c.consumer()
    }

![在这里插入图片描述][20210610104125506.png]  
然而实际什么都没有输出，这是因为生产者消费者执行方法时主线程已经结束了，给主线程加个时延

func main() { 
    	var p = producer{ }
    	var c = consumer{ }
    	go p.produce()
    	go c.consumer()
    	time.Sleep(time.Microsecond * 10)
    }

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3lqbjE5OTU_size_16_color_FFFFFF_t_70]

## 基于通道实现 ##

基于通道实现的这种方式需要注意避免从空通道中取数，否则就会出现死锁

var countChan chan int
    
    type producer struct { 
    }
    
    func (r *producer) produce() { 
    	for i := 0; i < 10; i++ { 
    		count := <-countChan
    		if count < 10 { 
    			count++
    			fmt.Printf("生产者生产了一个产品，当前存量%d\n", count)
    		} else { 
    			fmt.Printf("仓库满了，当前容量%d\n", count)
    		}
    		countChan <- count
    		var t = rand.Intn(100)
    		time.Sleep(time.Duration(t))
    	}
    }
    
    func (r *consumer) consumer() { 
    	for i := 0; i < 10; i++ { 
    		count := <-countChan
    		if count > 0 { 
    			count--
    			fmt.Printf("消费者消费了一个产品，当前存量%d\n", count)
    		} else { 
    			fmt.Printf("仓库空了，当前存量%d\n", count)
    		}
    		countChan <- count
    		var t = rand.Intn(100)
    		time.Sleep(time.Duration(t))
    	}
    }
    
    type consumer struct { 
    }
    
    func main() { 
    	countChan = make(chan int, 1)
    	countChan <- 0
    	var p = producer{ }
    	var c = consumer{ }
    	go p.produce()
    	go c.consumer()
    	time.Sleep(1000)
    }

## 基于select解决通道阻塞问题 ##

import (
    	"fmt"
    	"math/rand"
    	"time"
    )
    
    var countChan chan int
    
    type producer struct { 
    }
    
    func (r *producer) produce() { 
    	for i := 0; i < 10; i++ { 
    		select { 
    		case count := <-countChan:
    			if count < 10 { 
    				count++
    				fmt.Printf("生产者生产了一个产品，当前存量%d\n", count)
    			} else { 
    				fmt.Printf("仓库满了，当前容量%d\n", count)
    			}
    			countChan <- count
    			var t = rand.Intn(100)
    			time.Sleep(time.Duration(t))
    		default:
    			fmt.Println("初始化产品池")
    			countChan <- 0
    		}
    	}
    }
    
    func (r *consumer) consumer() { 
    	for i := 0; i < 10; i++ { 
    		select { 
    		case count := <-countChan:
    			if count > 0 { 
    				count--
    				fmt.Printf("消费者消费了一个产品，当前存量%d\n", count)
    			} else { 
    				fmt.Printf("仓库空了，当前存量%d\n", count)
    			}
    			countChan <- count
    			var t = rand.Intn(100)
    			time.Sleep(time.Duration(t))
    		default:
    			fmt.Println("初始化产品池")
    			countChan <- 0
    		}
    
    	}
    }
    
    type consumer struct { 
    }
    
    func main() { 
    	countChan = make(chan int, 1)
    	var p = producer{ }
    	var c = consumer{ }
    	go p.produce()
    	go c.consumer()
    	time.Sleep(10000)
    }

![在这里插入图片描述][20210610155920746.png]

[20210610104125506.png]: /images/20221005/ddef7dd985524bdd80c9f742077a984f.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3lqbjE5OTU_size_16_color_FFFFFF_t_70]: /images/20221005/1a46ff40b5fa49039565a10dc22b1ec1.png
[20210610155920746.png]: /images/20221005/9966ce0b8baf4b83a7c98759791ef59d.png