Question

我正在尝试为CPU调度程序模拟器实现循环算法，但使用链表结构。

我已经编写了这段代码，但似乎无法正常运行：

//Round Robin scheduling
void roundRobin(){

bubbleSortArrivalTime();

struct process *temp;
int totalTimeCnt=0;
int totalTime;
int quantum=4;
int i;

for(temp=proc; temp!=NULL; temp=temp->next){
totalTime+=temp->burstTime;

}

do{


for(i=1; i<LISTSIZE; i++){

if(i==1){
set_nth_process_burstTime(proc, i, get_nth_process_burstTime(proc,i)-quantum);

//set_nth_process_waitingTime(proc, i, get_nth_process_burstTime(proc,i-1)+get_nth_process_waitingTime(proc, i-1));

totalTime+=4;
}

else{
set_nth_process_burstTime(proc, i, get_nth_process_burstTime(proc,i)-quantum);
set_nth_process_waitingTime(proc, i, get_nth_process_burstTime(proc,i-1)+get_nth_process_waitingTime(proc, i-1));
totalTime+=4;
}

}


}while(totalTimeCnt!=0);


method="Method selected: Round Robin Scheduling";


}

我的链接列表的结构如下：

    struct process{
    int burstTime,arrivalTime, priority,pname;
    float waitingTime, turnArroundTime;
    struct process *next;
}*proc=NULL;

其中proc被定义为全局。

我已经实现了一些get和set函数来轻松访问任何元素：

void set_nth_process_burstTime(struct process*header, int position, int value)
void set_nth_process_waitingTime(struct process *header, int position, float value)
int get_nth_process_waitingTime(struct process *header, int position)
int get_nth_process_priority(struct process *header,int position)
int get_nth_process_arrivalTime(struct process *header,int position)
int get_nth_process_burstTime(struct process *header,int position)

请问您如何正确实施Round Robin？它没有给出正确的结果。

Answer 1

循环赛非常简单。在主函数中，在所有初始化，中断设置等之后，有：

while(1)
{
    process_1();
    process_2();
    process_3();
    ...
}

除此之外的任何事情都将归因于特定项目的一些特殊考虑因素。

实现scheduler + dispatcher，具有多个所需的执行间隔，优先级，条件状态，老化等是一种完全不同的架构。

对于round robin，上面的while()循环就是它。

对于一个真实的项目，您还需要：

某些中断驱动的定时和I / O进程，
处理看门狗定时器
温暖和冷启动模式
powerup BIT
连续BIT
命令BIT

Answer 2

    var Crawler = require("crawler");
var url = require('url');
var fs = require('fs');




var writeStream = fs.createWriteStream('./output');
writeStream.write('<?xml version="1.0" encoding="UTF-8"?><urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation=" http://www.sitemaps.org/schemas/sitemap/0.9 http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd">');

var strBuff = '<?xml version="1.0" encoding="UTF-8"?><urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" xmlns:xhtml="http://www.w3.org/1999/xhtml" xmlns:mobile="http://www.google.com/schemas/sitemap-mobile/1.0" xmlns:image="http://www.google.com/schemas/sitemap-image/1.1">';



var Router = require('routes');
var router = Router();
var noop = function(){};

var peroid = {
    '/':'hourly',
    '/results':'hourly',
    '/tips': 'hourly',
    '/tips/:country':'hourly',
    '/tips/:country/:venue':'hourly',
    '/support':'hourly',

}


function addToMap(url) {
    var key = router.match(url.replace('https://www.yourwebsite.com',''));
    if(!key) {
        key = {};
        key.route =  '/';
    } else {
        console.log('match ', url);
    }
    var route = key.route;
    var freq = peroid[route];
    var buf = '<url>\n<loc>'+url+'</loc>\n <changefreq>'+freq+'</changefreq>\n<priority>0.5</priority>\n</url>';
    strBuff += '<url>\n<loc>'+url+'</loc>\n <changefreq>'+freq+'</changefreq>\n<priority>0.5</priority>\n</url>';

    writeStream.write(buf);

}

function saveTofile() {
    console.log('end');
    writeStream.write('\n</urlset>');
    writeStream.end();
}



router.addRoute("/", noop);
router.addRoute("/tips", noop);
router.addRoute("/tips/:country", noop);
router.addRoute("/tips/:country/:venue", noop);
router.addRoute("/support", noop);
router.addRoute("/algorithm", noop);





var cache = {};

var c = new Crawler({
    maxConnections : 25,
    skipDuplicates: true,
    // This will be called for each crawled page
    onDrain: function () {
        console.log('ondrain');
        saveTofile();
    },
    callback : function (error, result, $) {
        if(error || !$) {
            console.log(error, result.uri);
            return;
        }
        $('a').each(function(index, a) {
            var toQueueUrl = $(a).attr('href');
            if(!toQueueUrl) {
                return;
            }

            if((toQueueUrl && toQueueUrl[0] !== '/') || toQueueUrl.indexOf('/api/') !== -1 || toQueueUrl.indexOf('.pdf') !== -1) {
                //console.log('not crawliing', toQueueUrl);
                return;
            }
            if(cache.hasOwnProperty(toQueueUrl) || !toQueueUrl) {
                return;
            }
            //console.log(toQueueUrl);
            c.queue('https://www.yourwebsite.com'+toQueueUrl);

            addToMap('https://www.yourwebsite.com'+toQueueUrl);

            cache[toQueueUrl]  = 1;

            var keyz = Object.keys(cache);
            if(! (keyz.length % 100) ) {
                console.log('total', keyz.length);
            }
        });
    }
});


c.queue('https://www.yourwebsite.com');

使用链表进行循环调度

2 个答案: