void run_simulation(int algorithm, int quantum)
{
switch(algorithm) {
case STRIDE:
stride_scheduling(quantum);
break;
case PS:
priority_scheduling();
break;
case RR:
rr_scheduling(quantum);
break;
case FCFS:
default:
first_come_first_serve();
break;
}
}
void stride_scheduling(int quantum)
{
total_priority = 0;
global_tickets = 10000;
/* divide tickets by piority */
int i,p;
for ( p =0; p<num_tasks; p++){
if (tasks[p].stride <= current_pass && tasks[p].finish_time == 0)
total_priority += tasks[p].priority;
}
if (total_priority == 0){
compute_and_print_stats();
exit(0);
}
for ( i =0; i<num_tasks; i++){
tasks[i].stride = tasks[i].priority * tasks[i].schedulings;
/*printf("Stride: %d %d \n", tasks[i].stride, current_pass);*/
if (global_tickets - tasks[i].tickets <=0){
/* printf ("Not enough tickets \n");*/
break;
}
if (tasks[i].stride > current_pass || tasks[i].finish_time != 0)
{
tasks[i].tickets = 0;
tasks[i].upperbound = 0;
global_tickets-= tasks[i].tickets;
tasks[i].lowerbound= 0;
current_pass++;
}
else{
/* printf("Total Priority : %d\n", total_priority);*/
tasks[i].tickets = tasks[i].priority *(10000/total_priority);
tasks[i].upperbound = global_tickets;
global_tickets-= tasks[i].tickets;
tasks[i].lowerbound= global_tickets+1;
/* printf(" Upper; %d Lower %d\n", tasks[i].upperbound, tasks[i].lowerbound);*/
}
}
srand ( time(NULL) );
int r = rand() % (10000 - global_tickets + 2);
r = 10000 - r;
int j;
for (j =0; j<num_tasks; j++)
{
if (tasks[j].upperbound >= r && r >= tasks[j].lowerbound)
{
/*task runs*/
if (tasks[j].length - quantum - tasks[j].cpu_cycles<=0 )
{
/* printf("Running task %d:\n\n" , j);*/
int p = tasks[j].length- tasks[j].cpu_cycles;
tasks[j].cpu_cycles += p;
tasks[j].schedulings +=1;
current_tick += p;
tasks[j].finish_time = current_tick;
/* printf("finish time %f current tick %d schedulings %d\n" , tasks[j].finish_time, current_tick, tasks[j].schedulings);*/
/* printf("TASK %d FINSIHED \\n\n\n", j);*/
current_pass++;
usleep(10000);
}
else {
/*printf("Running task %d:\n" , j);*/
tasks[j].cpu_cycles += quantum;
current_tick+= quantum;
tasks[j].schedulings += 1;
/* printf("Cycles %f current tick %d schedulings %d\n" , tasks[j].cpu_cycles, current_tick, tasks[j].schedulings);*/
current_pass++;
usleep(10000);
}
}
}
stride_scheduling(quantum);
printf("STRIDE SCHEDULING appears here\n");
exit(1);
}
