public AcquireTask(FixedChannelPool pool, TaskCompletionSource <IChannel> promise)
 {
     this.pool       = pool;
     this.Promise    = promise;
     this.ExpireTime = PreciseTimeSpan.FromTicks(Stopwatch.GetTimestamp()) + pool.acquireTimeout;
 }
 public TimeoutTask(FixedChannelPool pool, Action <AcquireTask> onTimeout)
 {
     this.pool      = pool;
     this.onTimeout = onTimeout;
 }