/// <summary>
/// Checks to see if deployment configuration has changed, by adding or removing silos.
/// If so, it updates the list of all silo names and creates a new resource balancer.
/// This should occure rarely.
/// </summary>
private BestFitBalancer <string, QueueId> GetBalancer()
{
var allSiloNames = deploymentConfig.GetAllSiloInstanceNames();
// rebuild balancer with new list of instance names
return(new BestFitBalancer <string, QueueId>(allSiloNames, allQueues));
}
/// <summary>
/// Called when the status of a silo in the cluster changes.
/// - Update list of silos if silos have been added or removed from the deployment
/// - Update the list of active silos
/// - Notify listeners if necessary
/// </summary>
/// <param name="updatedSilo">Silo which status has changed</param>
/// <param name="status">new silo status</param>
public void SiloStatusChangeNotification(SiloAddress updatedSilo, SiloStatus status)
{
bool changed = false;
var newSiloNames = deploymentConfig.GetAllSiloInstanceNames();
lock (activeSiloNames)
{
// if silo names has changed, deployment has been changed so we need to update silo names
changed |= UpdateAllSiloNames(newSiloNames);
// if a silo status has changed, update list of active silos
changed |= UpdateActiveSilos(updatedSilo, status);
}
// if no change, don't notify
if (changed)
{
NotifyListeners().Ignore();
}
}