golang channel 对比swoole chan 浅谈

先谈golang

package main

import (
    "fmt"
    "time"
)

//ex one 
func worker(id int, c chan int) {  
    for {
        fmt.Printf("is %d,come %c\n", id, <-c)
    }

}

//ex two return is a chan 
func createworker(id int) chan int {
    c := make(chan int)
    go func() {
        for {
            fmt.Printf("is %d,come %c\n", id, <-c)
        }
    }()
    return c
}

func chanDemo() {
    var channels [10]chan int
    //ex one
    for i := 0; i < 10; i++ {
        channels[i] = make(chan int)
        go worker(i, channels[i])
        channels[i] <- 'a' + i
        channels[i] <- 'A' + i
    }
    //extwo
    for i := 0; i < 10; i++ {
        channels[i] = createworker(i)
    }
    for i := 0; i < 10; i++ {
        channels[i] <- 'a' + i
    }
    for i := 0; i < 10; i++ {
        channels[i] <- 'B' + i
    }
    for i := 0; i < 10; i++ {
        channels[i] <- 'A' + i
    }
//like swoole co::sleep()
    time.Sleep(time.Microsecond)

}
func workerTwo(id int, c chan string) {
      //use your channal stop output
    for n := range c {

        fmt.Printf("is %d,come %s\n", id, n)
    }
}
//like swoole chan(3)
func bufferChannel() {
    c := make(chan string, 3)
    go workerTwo(0, c)
// input your channel
    c <- "苹果皮"
    c <- "豆腐皮"
    c <- "香蕉皮"
    close(c)
//  like swoole co::sleep() 
    time.Sleep(time.Microsecond)
}

func main() {
    chanDemo()
    bufferChannel()
}

再看swoole

/**
 * 创建一个主协程
 */
const NUM = 1; //总执行次数
$c = new chan(600); //定义管道
// 记录开始时间
$StartTime = time();
const MaxCoroutine = 10; //默认3000
Swoole\Coroutine::set(array(
    'max_coroutine' => MaxCoroutine,
));
go(function () use ($c) {
    /**
     * 连接数据库
     */
    $swoole_mysql = new Swoole\Coroutine\MySQL();
    $res = $swoole_mysql->connect([
        'host' => '127.0.0.1',
        'port' => 3306,
        'user' => 'root',
        'password' => 'root',
        'database' => 'demo',
        'fetch_mode' => true, //fetch 要开启这个
    ]);

    if ($res == false) {
        //  log($res);
        echo "MYSQL-CONNECT-ERROR" . PHP_EOL;
        return;
    }
    /**
     * 调用pop防止 堵塞 子协程
     */
    go(function () use ($c, $swoole_mysql) {
        popChan($c, $swoole_mysql);
    });
    /**
     * 调用push  子协程 
     */
    go(function () use ($c) {
        pushChan($c);
    });
});

/**
 * 调用pop
 *
 * @param [type] $c
 * @param [type] $swoole_mysql
 * @return void
 */
function popChan(&$c, &$swoole_mysql)
{
    $n = 0;
    $stm = $swoole_mysql->prepare('insert into `cate` (`id`,`name`) value(?,?)');

    if (false == $stm) {
        // log("预处理错误的原因:" . $swoole_mysql->erron . ":" . $swoole_mysql->error);
        consolelog("mysql 添加失败" . $swoole_mysql->error);
        die();
    }

    while (true) {
        consolelog("wite-begin-insert:" . date('Y-m-d H:i:s') . ":" . $n);
        //consolelog("insert-data:".json_encode($c->pop()));
        $n++;
        consolelog("begin-insert:" . date('Y-m-d H:i:s') . ":" . $n);
        $ret = $stm->execute([null, json_encode($c->pop())]);
        if (false == $ret) {
            //  log("添加错误的原因:" . $swoole_mysql->erron . ":" . $swoole_mysql->error);
            //consolelog('insert-error'. $swoole_mysql->erron() . ":" . $swoole_mysql->error());
            $n--; //回退
            $c->push($c->pop());
        }
        if (NUM == $n) {
            consolelog('End at : ' . date('Y-m-d H:i:s') . PHP_EOL
                . ' 耗时： ' . (time() - $GLOBALS['StartTime'])
                . 'S 速率： ' . round($n / (time() - $GLOBALS['StartTime']), 2) . '/S');
            return;
        }
    }
}
/**
 * push
 */
function pushChan(&$c)
{

    for ($i = 0; $i < NUM; $i++) {
        /**
         * 以防万一
         */
        while ($c->isFull() || (Swoole\Coroutine::stats())['coroutine_num'] > MaxCoroutine - 5) {
            consolelog("sleep:" . $i);
            co::sleep(0.3);
        }

        $data = [
            'www.baidu.com',
            'www.qq.com',
            'www.csdn.com',
        ];
        foreach ($data as $v) {
            $ips[] = co::gethostbyname($v, AF_INET, 0.5);
            consolelog("begin-select:" . $i);
        }
        $c->push($ips);
    }
}


/**
 * 定义打印输出
 *
 * @param [type] $msg
 * @return void
 */
function consolelog($msg)
{
    $msg = $msg . PHP_EOL;
    echo $msg;
}
/**
 * 定义日志文件
 *
 * @param [type] $msg
 * @return void
 */

因为协程是并行执行的他的速度非常快，如果不用time我们看不到他的执行结果,所以现在修改一下代码,也可以实现

package main

import (
    "fmt"
)

//create worker
func createWorker(id int) workers {
    w := workers{
        in: make(chan int),
        done: make(chan bool),
    }
    go doWorker(id, w.in, w.done)
    return w
}

// do worker
func doWorker(id int, c chan int, done chan bool) {

    for n := range c {

        fmt.Printf("is %d,come %c\n", id, n)
        done <- true //out
    }
}

type workers struct { //type a struct
    in   chan int //in channel
    done chan bool //out channel
}

func chanDemo() {
    var workers [10]workers
    //extwo
    for i := 0; i < 10; i++ {
        workers[i] = createWorker(i)
    }
    //all words goto channel
    for i, worker := range workers {
        worker.in <- 'a' + i

    }
//make word out
    for _, woker := range workers {
        <-woker.done
    } 
//all words goto channel
    for i, worker := range workers {
        worker.in <- 'A' + i

    }
//make word out
    for _, woker := range workers {
        <-woker.done
    }
    

}

func main() {
    chanDemo()

}

golang里面内置了一个WaitGroup方法 还可以这样来

package main

import (
    "fmt"
    "sync"
)

//create worker
func createWorker(id int, wait *sync.WaitGroup) workers {
    w := workers{
        in:   make(chan int),
        wait: wait,
    }
    go doWorker(id, w.in, wait)
    return w
}

// do worker
func doWorker(id int, c chan int, wait *sync.WaitGroup) {

    for n := range c {

        fmt.Printf("is %d,come %c\n", id, n)
        wait.Done()

    }
}

type workers struct {
    in   chan int
    wait *sync.WaitGroup //usr chanDemo wait so use  *
}

func chanDemo() {
    var workers [10]workers
    var wait sync.WaitGroup

    for i := 0; i < 10; i++ {
        workers[i] = createWorker(i, &wait)
    }
    wait.Add(20) //we have 20 work todo
    for i, worker := range workers {
        worker.in <- 'a' + i
        //or we can do this
        //wait.Add(1)
    }
    for i, worker := range workers {
        worker.in <- 'A' + i
    }
    wait.Wait() //wait 20 work to end
}

func main() {
    chanDemo()

}

总结:swoole的chan 类似于 队列，先进先出,可以设置一个缓存区,就是你的管道的长度, 在swoole里面有isFull方法进行判断,如果满了，可以将当前协程挂起，（其他判断方法也可以），如果发生I/O阻塞，协程本身就是并发,大家可以想想会发生什么,你的CPU，内存，所以代码一定要严谨。

go里面的channel是并行执行,因为速度非常快,我们第一种通过time的方式可以实现输出,第二种先并行执行前10个，done出来,再并行执行后10个，done出来,第三种,通过内置的waitgroup方法,并行执行20个。

-----个人理解