我一直在为这个调度程序项目工作一点。我目前遇到过一些我无法找到问题的事情。我可能会错过它，或者只是缺乏睡眠。我认为它发生在名为### MANAGing WAITING ###的代码块中。当我到达时间大约23时，它只是星星打印，事情已经完成了他们的IO爆发，而实际上在等待列表中应该只有1或2个进程。有人如何填补等候名单。我无法弄清楚为什么会这样。任何帮助将不胜感激。
//Scheduler Project
typedef struct PCB{
int pID;
int arrivalTime;
int totalBurst;
int cpuBursts[10];
int ioBursts[10];
int waited;
int currentCPUBurst;
int currentIOBurst;
int burstsRemaining;
struct PCB* next;
struct PCB* prev;
}PCB;
//#####################Creating Queues#####################
//Init queue head and tail
PCB* iHead = NULL;
PCB* iTail = NULL;
//Ready queue head and tail
PCB* rHead = NULL;
PCB* rTail = NULL;
//Waiting list head and tail
PCB* wHead = NULL;
PCB* wTail = NULL;
int Timer = 0;
PCB* running = NULL;
void calculateProcessStats();
//#####################Enqueues#####################
//Adds item to the back of init queue
void iEnqueue(PCB* item)
{
if(iHead == NULL) //Queue is empty.
iHead = iTail = item;
else{
iTail->next = item;
item->prev = iTail;
iTail = item;
iTail->next = NULL;
}
}
//Adds item to the back of ready queue
void rEnqueue(PCB* item)
{
if(rHead == NULL) //Queue is empty.
rHead = rTail = item;
else{
rTail->next = item;
item->prev = rTail;
rTail = item;
rTail->next = NULL;
}
printf("Process %d has arrived\n", rTail->pID);
}
//Adds item to the back of waiting list
void wInsert(PCB* item)
{
if(wHead == NULL) //List is empty is empty.
wHead = wTail = item;
else{
wTail->next = item;
item->prev = wTail;
wTail = item;
wTail->next = NULL;
}
}
//####################Dequeues##########################
//Removes item from front/head of the queue
PCB* iDequeue()
{
PCB* temp = iHead;
if(iHead == NULL) //Queue is empty.
return 0;
else if(iHead==iTail && iHead != NULL){ //Single PCB in queue
//free(iHead);
iHead = NULL;
}
else{ //Two or more PCBs in queue
iHead = iHead->next;
//free(temp);
iHead->prev = NULL;
}
return temp;
}
//Removes item from front/head of the queue
PCB* rDequeue()
{
PCB* temp = rHead;
if(rHead == NULL) //Queue is empty.
return 0;
else if(rHead==rTail && rHead != NULL){ //Single PCB in queue
//free(rHead);
rHead = NULL;
}
else{ //Two or more PCBs in queue
rHead = rHead->next;
//free(temp);
rHead->prev = NULL;
}
return temp;
}
//Removes node passed to functions. This is working on a queue
void wRemove(PCB* item)
{
PCB* temp = wHead;
while(temp != NULL)
{
if((temp->next == NULL) && (temp->pID == item->pID)){
wHead = NULL;
wTail = NULL;
}
else if(temp->pID == item->pID){
temp->prev->next = temp->next;
temp->next->prev = temp->prev;
}
temp = temp->next;
}
}
//Prints init queue head to tail
void iPrintQueue()
{
PCB* temp = iHead;
while(temp != NULL){
printf("pid=%d ", temp->pID);
printf("N=%d ", temp->burstsRemaining);
printf("Arrival Time=%d ", temp->arrivalTime);
printf("cpuBursts:");
for(int i = 0; i < 9; i++){
if(temp->cpuBursts[i] == 0)
break;
printf("%d ", temp->cpuBursts[i]);
}
printf("\n ioBursts:");
for(int i = 0; i < 9; i++){
if(temp->ioBursts[i] == 0)
break;
printf("%d ", temp->ioBursts[i]);
}
printf("\n");
temp = temp->next;
}
}
//Prints ready queue head to tail
void rPrintQueue()
{
PCB* temp = rHead;
while(temp != NULL){
printf("pid = %d ", temp->pID);
printf("N=%d ", temp->burstsRemaining);
printf("Arrival Time=%d ", temp->arrivalTime);
printf("cpuBursts:");
for(int i = 0; i < 9; i++){
if(temp->cpuBursts[i] == 0)
break;
printf("%d ", temp->cpuBursts[i]);
}
printf("\n ioBursts:");
for(int i = 0; i < 9; i++){
if(temp->ioBursts[i] == 0)
break;
printf("%d ", temp->ioBursts[i]);
}
printf("\n");
temp = temp->next;
}
}
int main(int argc, char *argv[])
{
//argv[0] = scheduler.cc
//argv[1] = input file to read from
//argv[2] = scheduling algorithm
//argv[3] = quantum
//argv[4] = cost of full context switch
//This section opens files and write it to init queue (iHead, iTail)
FILE *file = fopen (argv[1], "r");
if (file != NULL){ //Continue until entire file is empty
char line [64];
int pidCounter = 0;
while(fgets(line, sizeof line, file) != NULL){ //Grabs first line and puts stores in line, loops
char* token = strtok(line, " ");
PCB* temp = malloc(sizeof(PCB));
int tokenCounter = 1;
int cpuBurstCounter = 0;
int ioBurstCounter = 0;
while(token){ //Loops on single line, each iteration is the next token
if(tokenCounter == 1){
temp->arrivalTime = atoi(token);
}
else if(tokenCounter == 2){
temp->burstsRemaining = atoi(token);
}
else if(tokenCounter %2 == 1){ //Everything > 2 and odd (cpuBurst)
temp->cpuBursts[cpuBurstCounter] = atoi(token);
cpuBurstCounter++;
}
else { //Everything > 2 and even (ioBurst)
temp->ioBursts[ioBurstCounter] = atoi(token);
ioBurstCounter++;
}
token = strtok(NULL, " "); //Moves onto next token
tokenCounter++;
}
temp->pID = pidCounter;
pidCounter++;
temp->currentIOBurst = 0;
temp->currentCPUBurst = 0;
temp->waited = 0;
iEnqueue(temp);
}
fclose (file);
}
else{
perror (argv[1]);
}
if((strcmp(argv[2], "FCFS") == 0) && (argc == 3)){ //First Come First Served NonPreemptive Algorithm
while(1){
Timer++;
int timeLeft;
printf("Time=%d\n", Timer);
//##########MANAGE READY QUEUE##########
if(iHead != NULL){
while(iHead->arrivalTime == Timer){
rEnqueue(iDequeue());
}
}
//##########MANAGE RUNNING##########
//Should only be entered during first iteration and after running is finished or sent to wait
if((running == NULL) && (rHead != NULL)){
running = rDequeue();
timeLeft = running->cpuBursts[running->currentCPUBurst];
}
//Should enter this every time this is something running
if(running != NULL){
if(timeLeft == 0){
if(running->burstsRemaining <= running->currentCPUBurst){
calculateProcessStats();
free(running);
}
wInsert(running);
running->currentCPUBurst++;
printf("Process %d is waiting\n", running->pID);
running=NULL;
}
else{
timeLeft--;
printf("Process %d is running\n", running->pID);
}
}
//##########MANAGE WAITING QUEUE##########
PCB* wTemp = wHead;
while(wTemp != NULL){
wTemp->waited++;
printf("pid=%d > ", wTemp->pID);
/*
if(wTemp->waited == wTemp->ioBursts[wTemp->currentIOBurst]){
printf("Process %d has completed IO and returned to Ready state", wTemp->pID);
wRemove(wTemp);
}
*/
wTemp = wTemp->next;
}
//Remove this to have entire scheduler run
getchar();
printf("________________________________________________________________\n");
}
}
else if((strcmp(argv[2], "FCFS") == 0) && (argc == 5)){ //First Come First Server Preemptive Algorithm
//argv[3] = quantum
//argv[4] = cost of full context switch
printf("This is the code for FCFS Preemptive");
int quantum = atoi(argv[3]);
int csCost = atoi(argv[4]);
for(int i = 0; i < quantum; i++){
}
}
else if(strcmp(argv[2], "SJNFP") == 0){ //Shortest Job Next Algorithm
printf("This is the code for SJNFP");
//create a sort function for ready queue to keep queue sorted by cpuBursts[currentCPUBurst]
//dequeue from ready queue into running
}
else{
printf("Error: The algorithm for %s does not exist\n", argv[2]);
printf("Please use FCFS or SJNFP or check number of parameters for FCFS\n");
}
//When all processes finish
//printf("Finished\nCPU Utilization: Avg/Max TAT=%f/%f, Avg/Max Wait Time=%f/%f, Avg/Max Response Time=%f/%f\n", avgTAT, maxTAT, avgWaitTime, maxWaitTime, avgResponseTime, maxResponseTime)
return 0;
}
void calculateProcessStats(){
int TAT = Timer - running->arrivalTime;
int burstTime = 0;
for(int i = 0; i < running->totalBurst; i++)
burstTime += running->cpuBursts[i];
int waitTime = TAT - burstTime;
int ioTime = 0;
for(int i = 0; i < running->totalBurst-1; i++)
ioTime += running->ioBursts[i];
printf("Process %d terminated: TAT=%d, Wait Time=%d, I/O Wait=%d\n", running->pID, TAT, waitTime, ioTime);
}