fifo.cpp

本程序给出了SSD5实验课中Optional Exercise2的参考程序 内附有详细的注释 下载后请仔细参照源代码进行分析 切莫完全搬照

#include "fifo.h"
#include <FSTREAM>
using namespace std;
fifo::fifo(int seconds_per_page):simulator(seconds_per_page)
{
}
void fifo::simulate_arbitrary(string file)
{
	string outfile ="arbitray.out";
	ofstream osf(outfile.c_str());
	loadworkload(file);
	osf<<"Simulating!"<<endl;
	int finish_time = 0;
	float agg_latency = 0;
	float mean_latency;
	int totaljob =0;
	event evt;
	for(int time =1;!waiting.empty()||!workload.empty();time++)
	{		
		//requesting print event is coming !
		while(!workload.empty() && time == workload.front().arrival_time())
		{			
			evt= workload.front();
			osf<<"\tArriving: "<<evt.getjob()<<" at "<<time<<" seconds"<<endl;
			waiting.push(workload.front());
			workload.pop();
 		}
		//do the print job !
		if(!waiting.empty() && time >= finish_time)
		{
			totaljob ++;
			agg_latency += time - evt.arrival_time();
			evt = waiting.front();
			osf<<"\tServicing: "<<evt.getjob()<<" at "<<time<<" seconds"<<endl;
			waiting.pop();
			finish_time = time + evt.getjob().getnumpages() * seconds_per_page;
		}
	}
	osf<<"\n\ttotal job "<<totaljob<<endl;
	osf<<"\taggregate latency: "<<agg_latency<<" seconds"<<endl;
	mean_latency = agg_latency / totaljob;
	osf<<"\tmean latency : "<<mean_latency<<" seconds "<<endl;
	
	osf.close();
}
void fifo::simulate_bigfirst(string file)
{
	string outfile = "bigfirst.out";
	ofstream osf(outfile.c_str());
	loadworkload(file);
	osf<<"Simulating!"<<endl;
	int finish_time = 0;
	float agg_latency = 0;
	float mean_latency;
	int totaljob =0;
	event evt;
	for(int time =1;!priority_waiting.empty()||!workload.empty();time++)
	{		
		//requesting print event is coming !
		while(!workload.empty() && time == workload.front().arrival_time())
		{			
			evt= workload.front();
			osf<<"\tArriving: "<<evt.getjob()<<" at "<<time<<" seconds"<<endl;
			priority_waiting.push(workload.front());
			workload.pop();
 		}
		//do the print job !
		if(!priority_waiting.empty() && time >= finish_time)
		{
			totaljob ++;
			agg_latency += time - evt.arrival_time();

			evt = priority_waiting.top();
			osf<<"\tServicing: "<<evt.getjob()<<" at "<<time<<" seconds"<<endl;
			priority_waiting.pop();
			finish_time = time + evt.getjob().getnumpages() * seconds_per_page;
		}
	}
	osf<<"\n\ttotal job "<<totaljob<<endl;
	osf<<"\taggregate latency: "<<agg_latency<<" seconds"<<endl;
	mean_latency = agg_latency / totaljob;
	osf<<"\tmean latency : "<<mean_latency<<" seconds "<<endl;
	
	osf.close();
}
void fifo::simulate(string file)
{
	if(file.find("arbitrary")!= string::npos)
	{
		simulate_arbitrary(file);
		cout<<"The log file name is arbitrary.out"<<endl;
		return;
	}
	if(file.find("bigfirst") != string::npos)
	{
		simulate_bigfirst(file);
		cout<<"The log file name is arbitrary.out"<<endl;
		return;
	}
	cerr<<"The program don't know what algorithm to use"<<endl;
	cerr<<"You should specify the file name with arbitrary or bigfirst"<<endl;
}
bool operator < (event evtleft,event evtright)
{
	return evtleft.getjob().getnumpages() < evtright.getjob().getnumpages();
}