public int GetFreeServer(int arrival, int lastEndTime)
{
int retVal = -1;
if (this.serverSelectionMode == ServerSelectionMode.highestPriority)
{
int ID = -1;
for (int j = servers.Count - 1; j >= 0; j--) //Start searching for a free server starting from least priority.
{
if (servers[j].GetTimeServiceEnds() <= arrival) //Server is free.
{
ID = j;
}
}
if (ID == -1)//No free servers? Select the closest free one.
{
int soonestTime = int.MaxValue;
for (int j = servers.Count - 1; j >= 0; j--)
{
if (servers[j].GetTimeServiceEnds() <= soonestTime)
{
ID = j;
soonestTime = servers[j].GetTimeServiceEnds();
}
}
}
retVal = ID;
}
else if (serverSelectionMode == ServerSelectionMode.random)
{
List <int> serversID = new List <int>();
for (int j = 0; j < servers.Count; j++)//A list of free servers.
{
if (servers[j].GetTimeServiceEnds() <= arrival)
{
serversID.Add(j);
}
}
if (serversID.Count != 0)
{
retVal = serversID[RandomValue.getRandom(0, serversID.Count - 1)];//Pick any random free server.
}
else
{
//Pick the nearest free server if no one is free
serverSelectionMode = ServerSelectionMode.highestPriority;
retVal = GetFreeServer(arrival, lastEndTime);
serverSelectionMode = ServerSelectionMode.random;
}
}
else if (serverSelectionMode == ServerSelectionMode.leastUtilization)
{
double maxIdle = -1;
int maxIdleID = -1;
for (int j = 0; j < servers.Count; j++)//Assign to server with maximum idle time.
{
if (servers[j].GetIdle(lastEndTime) > maxIdle)
{
maxIdle = servers[j].GetIdle(lastEndTime);
maxIdleID = j;
}
}
retVal = maxIdleID;
}
return(retVal);
}
public int RandomProbability()
{
return(RandomValue.getRandom(0, 100));
}