/// <summary>
/// This method recalculate the new poll chain for the listener and deadletter listener collection
/// and swaps the new collection in atomically. This is done on a schedule to ensure that the collection priority
/// does not become stale, and that the most active clients receive the most amount of attention.
/// </summary>
/// <param name="rebuild">This boolean property specifies whether the collection should be rebuilt or reordered. True rebuilds the collection.</param>
private Task ListenersPriorityRecalculate(bool rebuild = true)
{
if (Status != ServiceStatus.Running)
{
return(Task.FromResult(0));
}
if (!rebuild && mClientCollection != null)
{
mClientCollection.Reprioritise();
}
try
{
//We do an atomic switch to add in a new priority list.
var newColl = new ClientPriorityCollection(mListener
, mResourceTracker
, mPolicy.ListenerClientPollAlgorithm
, Interlocked.Increment(ref mListenersPriorityIteration));
//Switch out the old collection for the new collection atomically
var oldColl = Interlocked.Exchange(ref mClientCollection, newColl);
//Close the old collection, note that it will be null the first time.
oldColl?.Close();
Collector?.LogMessage(LoggingLevel.Trace, $"ListenersPriorityRecalculate completed {mListenersPriorityIteration}.");
}
catch (Exception ex)
{
Collector?.LogException("ListenersPriorityCalculate failed. Using the old collection.", ex);
}
return(Task.FromResult(0));
}
/// <summary>
/// This method starts the listener and prioritises the clients.
/// </summary>
public override void Start()
{
base.Start();
Clients = new ClientPriorityCollection(new IListener[] { Service }.ToList(), null, PollAlgorithm, 0);
}
