private static Distribution[] CreateServiceDistributions(Data data, Random rng)
{
Distribution[] serviceDistributions = new Distribution[data.nrServers];
for (int i = 0; i < data.nrServers; i++)
{
switch (data.ServerParameters[i].Type)
{
case "Deterministic":
serviceDistributions[i] = new DeterministicDistribution(rng, data.ServerParameters[i].Average, data.ServerParameters[i].CV);
break;
case "Uniform":
serviceDistributions[i] = new UniformDistribution(rng, data.ServerParameters[i].Average, data.ServerParameters[i].CV);
break;
case "Exponential":
serviceDistributions[i] = new ExponentialDistribution(rng, data.ServerParameters[i].Average, data.ServerParameters[i].CV);
break;
case "HyperExponential2":
serviceDistributions[i] = new Hyper2ExponentialDistribution(rng, data.ServerParameters[i].Average, data.ServerParameters[i].CV);
break;
}
}
return(serviceDistributions);
}
private static Distribution[] CreateArrivalDistributions(Data data, Random rng, double lambda)
{
Distribution[] arrivalDistributions = new Distribution[data.nrCustomers];
for (int i = 0; i < data.nrCustomers; i++)
{
arrivalDistributions[i] = new ExponentialDistribution(rng, 1 / (data.CustomerParameters[i].Fraction * lambda), 1);
}
return(arrivalDistributions);
}
static void Main(string[] args)
{
Console.WriteLine("QUEUING SIMULATION", new String('\u2500', 80));
Console.WriteLine("Simulation started...");
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
// Create a directory and file to print the results
string path = string.Concat(Environment.CurrentDirectory, "/Results/");
System.IO.Directory.CreateDirectory(path);
string filename = string.Concat(path, "Results_U.csv");
using (System.IO.StreamWriter file = new System.IO.StreamWriter(filename, false))
{
file.WriteLine("utilization,meanW,meanS,meanLq,meanLs,meanPW,theoreticPWMMC,meanWEstimation");
}
// Runs (Number and time span resp.)
int R = 6;
double T = 1E6;
// Pseudo-random number generator
//Random rng = new Random();
ThreadLocal <Random> rng = new ThreadLocal <Random>(() => new Random());
int counter = new int();
Parallel.For(1, 20, new ParallelOptions {
MaxDegreeOfParallelism = 3
}, rho => // MaxDegreeOfParallelism n + 1, where n is the number of cores
{
// Diagnosis
//bool repeat = rng.IsValueCreated;
//Console.WriteLine("ThreadName = {0} {1}", rng.Value, repeat ? "(repeat)" : "");
// Initialize servers
//double[] serviceDistributionParameters = new double[] { 1, 1, 1, 1 };
double[,] serviceDistributionParameters = new double[, ] {
{ 0, 2 }, { 0, 2 }, { 0, 2 }, { 0, 2 }
};
//double[] serviceDistributionParameters = new double[] { 1, 1, 1, 1 };
//double[,] serviceDistributionParameters = new double[,] { { 1, 2 }, { 1, 2 }, { 1, 2 }, { 1, 2 } };
int nrServers = serviceDistributionParameters.GetLength(0);
Distribution[] serviceDistributions = new Distribution[nrServers];
for (int i = 0; i < nrServers; i++)
{
//serviceDistributions[i] = new DeterministicDistribution(rng.Value, serviceDistributionParameters[i]);
serviceDistributions[i] = new UniformDistribution(rng.Value, serviceDistributionParameters[i, 0], serviceDistributionParameters[i, 1]);
//serviceDistributions[i] = new ExponentialDistribution(rng.Value, serviceDistributionParameters[i]);
//serviceDistributions[i] = new Hyper2ExponentialDistribution(rng.Value, serviceDistributionParameters[i, 0], serviceDistributionParameters[i, 1]);
}
// Exponential arrival rate
double lambda = nrServers * (rho / 20.0);
// Initialize customers
double[] arrivalDistributionParameters = new double[] { lambda };
int nrCustomers = arrivalDistributionParameters.Length;
Distribution[] arrivalDistributions = new Distribution[nrCustomers];
for (int i = 0; i < nrCustomers; i++)
{
arrivalDistributions[i] = new ExponentialDistribution(rng.Value, arrivalDistributionParameters[i]);
}
// Server-Customer Eligibility
bool[][] eligibility = new bool[nrServers][];
for (int i = 0; i < nrServers; i++)
{
bool[] tmp = new bool[nrCustomers];
for (int j = 0; j < nrCustomers; j++)
{
tmp[j] = true;
}
eligibility[i] = tmp;
}
// Main simulation loop
Results results = new Results(R, nrServers, nrCustomers, filename);
for (int r = 0; r < R; r++)
{
double t = 0;
FutureEvents futureEvents = new FutureEvents();
for (int i = 0; i < nrCustomers; i++)
{
Customer customer = new Customer(i);
futureEvents.Add(new Event(Event.ARRIVAL, arrivalDistributions[i].Next(), customer));
}
CustomerQueue customerQueue = new CustomerQueue();
ServerQueue idleServerQueue = new ServerQueue();
for (int i = 0; i < nrServers; i++)
{
Server server = new Server(i, eligibility[i]);
idleServerQueue.Add(server);
}
while (t < T)
{
Event e = futureEvents.Next();
t = e.time;
results.Register(r, e, customerQueue, idleServerQueue);
if (e.type == Event.ARRIVAL)
{
customerQueue.CustomerCheckIn(e.customer, t);
Server server = idleServerQueue.FindServer(e.customer.cID);
if (server != null) // Eligible server available
{
idleServerQueue.Remove(server);
e.customer.server = server;
e.customer.serviceTime = t;
e.customer.departureTime = t + serviceDistributions[server.sID].Next();
futureEvents.Add(new Event(Event.DEPARTURE, e.customer.departureTime, e.customer));
}
futureEvents.Add(new Event(Event.ARRIVAL, t + arrivalDistributions[e.customer.cID].Next(), new Customer(e.customer.cID)));
}
else if (e.type == Event.DEPARTURE)
{
Customer customer = customerQueue.FindCustomer(e.customer.server);
if (customer != null)
{
customer.serviceTime = t;
customer.departureTime = t + serviceDistributions[customer.server.sID].Next();
futureEvents.Add(new Event(Event.DEPARTURE, customer.departureTime, customer));
}
else
{
idleServerQueue.Add(e.customer.server);
}
customerQueue.CustomerCheckOut(e.customer);
}
else
{
Console.WriteLine("Invalid event type.");
}
}
}
results.GetMeans(rho / 20.0, serviceDistributions[0].residual);
counter++;
Console.WriteLine("\r{0}", counter);
});
Console.WriteLine("\nSimulation complete.\nTotal elapsed time {0:0.00} minutes", stopwatch.ElapsedMilliseconds / 1000 / 60);
//Console.ReadLine();
}