Concurrency in Go: A Call Center Tutorial

[oldman]

讲channel 和 Goroutine的一篇blog（应该不用翻墙）
http://www.mprescient.com/journal/2011/1/9/concurrency-in-go-a-call-center-tutorial.html

[chai]

确实不要翻墙 :)

在 2011年1月10日 下午2:23，oldman <fenghaun...@gmail.com>写道：

讲channel 和 Goroutine的一篇blog（应该不用翻墙）
http://www.mprescient.com/journal/2011/1/9/concurrency-in-go-a-call-center-tutorial.html

--
chaishushan

[oldman]

今天又仔细看了下这篇blog，感觉博文下面的评论也蛮不错的，按照 Jesper Louis Andersen 的思路我重新写了一遍，附在下面，有啥问题欢迎指正。

PS 1：当然如果是队列实现，这篇文章的代码就基本足矣了

PS 2：这个Thread的第一封邮件少了“应用”，应该为“讲channel 和 Goroutine应用的一篇blog”




package main

 

import (

    "fmt"

    "time"

    "rand"

)

 

type Call struct {

    id         int

    duration   int

    start_time int64

    end        chan bool

}

 

func (c *Call) Wait() {

    <-c.end

}

 

type Agent struct {

    id int

    cc *CallCenter

}

 

func (ag *Agent) Run(c *Call) {

    fmt.Printf("Agent: %d, answering Call: %d\n", ag.id, c.id)

    time.Sleep(int64(c.duration * 1000000))

    fmt.Printf("Call %d answered; waited %d milliseconds\n", c.id, (time.Nanoseconds()-c.start_time)/1000000)

}

 

func (ag *Agent) Becomeidle(cc *CallCenter) {

    cc.idleagents <- ag

}

 

type CallCenter struct {

    allagents  []Agent

    idleagents chan *Agent

}

 

func (cc *CallCenter) Open(agentnum int) {

    fmt.Println("Call center opening")

    cc.allagents = make([]Agent, agentnum)

    cc.idleagents = make(chan *Agent, agentnum)

    for _, ag := range cc.allagents {

        (&ag).Becomeidle(cc)

    }

    fmt.Println("Call center open")

}

 

func (cc *CallCenter) Close() {

    fmt.Println("Call center closing")

    close(cc.idleagents)

    fmt.Println("Call center closed")

}

 

func handle(cc *CallCenter, c *Call) {

    ag := <-cc.idleagents

    ag.Run(c)

    ag.Becomeidle(cc)

    c.end <- true

}

 

func elapse(tip string, begin int64) {

    end := time.Nanoseconds()

    fmt.Printf("%s: %d seconds\n", tip, (end-begin)/1000000000)

}

 

func main() {

    num_agents := 1

    num_calls := 10

    max_dur := 5

    call_center := new(CallCenter)

 

    defer elapse("All Time", time.Nanoseconds())

 

    call_center.Open(num_agents)

    allc := make([]*Call, num_calls)

    for i := 0; i < num_calls; i++ {

        allc[i] = &Call{i, rand.Int() * max_dur, time.Nanoseconds(), make(chan bool)}

    }

 

    for _, c := range allc {

        go handle(call_center, c)

    }

 

    for _, c := range allc {

        c.Wait()

    }

    call_center.Close()

}

2011/1/10 chai <chais...@gmail.com>

[oldman]

呃。。。排版有点问题，附纯文本版本吧

2011/1/12 oldman <fenghaun...@gmail.com>