void IDispatchHost.IncreaseThreadCount(string reason)
{
// check if thread pool is already awaiting another thread
if (_threadVelocity > 0)
{
return;
}
lock (_syncRoot) {
_threadVelocity = 1;
// check if thread pool has enough threads
if (_threadCount >= _maxParallelThreads)
{
_threadVelocity = 0;
return;
}
#if EXTRA_DEBUG
_log.DebugFormat("IncreaseThreadCount: {1} - {0}", this, reason);
#endif
}
// check if there are threads in the reserve
KeyValuePair <DispatchThread, Result <DispatchWorkItem> > reservedThread;
if (_reservedThreads.TryPop(out reservedThread))
{
AddThread(reservedThread);
}
else
{
DispatchThreadScheduler.RequestThread(0, AddThread);
}
}
//--- Constructors ---
/// <summary>
/// Creates a new ElasticThreadPool instance.
/// </summary>
/// <param name="minReservedThreads">Minium number of threads to reserve for the thread pool.</param>
/// <param name="maxParallelThreads">Maximum number of parallel threads used by the thread pool.</param>
/// <exception cref="InsufficientResourcesException">The ElasticThreadPool instance was unable to obtain the minimum reserved threads.</exception>
public ElasticThreadPool(int minReservedThreads, int maxParallelThreads)
{
_minReservedThreads = Math.Max(0, Math.Min(minReservedThreads, MAX_RESERVED_THREADS));
_maxParallelThreads = Math.Max(Math.Max(1, minReservedThreads), Math.Min(maxParallelThreads, int.MaxValue));
// initialize reserved threads
_activeThreads = new DispatchThread[Math.Min(_maxParallelThreads, Math.Max(_minReservedThreads, Math.Min(16, _maxParallelThreads)))];
if (_minReservedThreads > 0)
{
DispatchThreadScheduler.RequestThread(_minReservedThreads, AddThread);
}
DispatchThreadScheduler.RegisterHost(this);
_log.DebugFormat("Create @{0}", this);
}
//--- Constructors ---
/// <summary>
/// Creates a new ElasticPriorityThreadPool instance.
/// </summary>
/// <param name="minReservedThreads">Minium number of threads to reserve for the thread pool.</param>
/// <param name="maxParallelThreads">Maximum number of parallel threads used by the thread pool.</param>
/// <param name="maxPriority">Maximum priority number (inclusive upper bound).</param>
/// <exception cref="InsufficientResourcesException">The ElasticPriorityThreadPool instance was unable to obtain the minimum reserved threads.</exception>
public ElasticPriorityThreadPool(int minReservedThreads, int maxParallelThreads, int maxPriority)
{
_minReservedThreads = Math.Max(0, Math.Min(minReservedThreads, MAX_RESERVED_THREADS));
_maxParallelThreads = Math.Max(Math.Max(1, minReservedThreads), Math.Min(maxParallelThreads, int.MaxValue));
_inbox = new LockFreePriorityQueue <Action>(maxPriority);
_prioritizedInbox = new PrioritizedThreadPool[maxPriority];
for (int i = 0; i < maxPriority; ++i)
{
_prioritizedInbox[i] = new PrioritizedThreadPool(i, this);
}
// initialize reserved threads
_activeThreads = new DispatchThread[Math.Min(_maxParallelThreads, Math.Max(_minReservedThreads, Math.Min(16, _maxParallelThreads)))];
if (_minReservedThreads > 0)
{
DispatchThreadScheduler.RequestThread(_minReservedThreads, AddThread);
}
DispatchThreadScheduler.RegisterHost(this);
_log.DebugFormat("Create @{0}", this);
}
