撸过 tcp 的话应该知道要能处理多个客户端，就得用 IO 复用技术【事件多路分发器】或是多进程以及多线程，每来一个客户端就 fork 一个进程或是线程，那样的话上下文切换成本特别高，所以咱们先创建好一组进程【进程池】，等客户端连接上来的时候，通过某种算法【我们用的轮询】来选择某个进程投递任务来干活，这样的话就不用创建又销毁来回折腾了，提升它的效率。下面是 PHP 代码版本的实现
?php
/**
* Created by PhpStorm.
* User: 1655664358@qq.com
* Date: 2019/1/12
* Time: 16:18
*/
$flag = 1;
class process
{
public $pid;
public $name;
public $file;
public $num;
}
class instance
{
public $processIdx;
public $proc = [];
public $processNum;
}
function sigHandler($sigNo)
{
global $flag;
$flag = 0;
echo "信号中断处理".PHP_EOL;
}
function processPool(instance $instance,$num)
{
if (!$instance||$num==0){
fprintf(STDERR,"%s","参数错误");
return 1;
}
$instance->processIdx = 0;
$instance->processNum = $num;
pcntl_signal(SIGINT,'sigHandler');
pcntl_signal(SIGTERM,'sigHandler');
$process = new process();
for ($i=1;$i=$num;$i++){
$instance->proc[$i] = clone $process;
$instance->proc[$i]->file = $i;
$instance->proc[$i]->pid = pcntl_fork();
$instance->processIdx = $i;
if ($instance->proc[$i]->pid0){
exit("进程创建失败");
}
else if ($instance->proc[$i]->pid>0){
//nothing
continue;
}else{
worker($instance);
}
}
master($instance);
$exitProcess= [];
while (1){
for ($i=1;$i=$num;$i++){
//非阻塞方式回收子进程
pcntl_waitpid($instance->proc[$i]->pid,$status,WNOHANG);
if ($status){
$exitProcess[] = $instance->proc[$i]->pid;
fwrite(STDOUT,"worker#".$instance->proc[$i]->pid."-".$status,30);
}
}
if (count($exitProcess)==$instance->processNum){
exit(0);
}
usleep(1000);
}
}
//简单的轮询算法 自己可以用队列，随机，链表，栈链，二叉树啥的折腾
function roundRobin($instance,$roll)
{
/** @var instance $instance */
return $instance->proc[$roll%$instance->processNum+1];
}
function master($instance)
{
/** @var instance $instance */
fprintf(STDOUT,"master 进程 %d\n",$instance->processIdx);
global $flag;
$roll = 0;
while ($flag){
pcntl_signal_dispatch();
/** @var process $process */
$process = roundRobin($instance,$roll++);
echo "轮询的进程:".$process->pid.PHP_EOL;
$file = $process->file;
posix_mkfifo($file,0666);
$fd = fopen($file,"w");
fwrite($fd,"hi",2);
sleep(1);
}
for ($i=1;$i=$instance->processNum;$i++){
posix_kill($instance->proc[$i]->pid,9);
}
fprintf(STDOUT,"master shutdown %d\n",$instance->processIdx);
}
function getProcess($instance)
{
/** @var instance $instance */
return $instance->proc[$instance->processIdx];
}
function worker($instance)
{
/** @var process $process */
$process = getProcess($instance);
while (1){
$file = $process->file;
posix_mkfifo($file,0666);
$fd = fopen($file,"r");
$content = fread($fd,10);
fprintf(STDOUT,"worker#%d读取的内容：%s file=%d\n",posix_getpid(),$content,$file);
}
exit(0);
}
$instance = new instance();
processPool($instance,5);
