예제 #1
0
        internal void Release(NpgsqlConnector connector)
        {
            // If Clear/ClearAll has been been called since this connector was first opened,
            // throw it away.
            if (connector.ClearCounter < _clearCounter)
            {
                try
                {
                    connector.Close();
                }
                catch (Exception e)
                {
                    Log.Warn("Exception while closing outdated connector", e, connector.Id);
                }

                lock (this)
                    Busy--;
                return;
            }

            if (connector.IsBroken)
            {
                lock (this)
                    Busy--;
                return;
            }

            connector.Reset();
            lock (this)
            {
                // If there are any pending open attempts in progress hand the connector off to
                // them directly.
                while (Waiting.Count > 0)
                {
                    var tcs = Waiting.Dequeue();
                    // Some attempts may be in the queue but in cancelled state, since they've already timed out.
                    // Simply dequeue these and move on.
                    if (tcs.Task.IsCanceled)
                    {
                        continue;
                    }
                    // We have a pending open attempt. "Complete" it, handing off the connector.
                    // We do this in another thread because we don't want to execute the continuation here.
                    Task.Run(() => tcs.SetResult(connector));
                    return;
                }

                Idle.Push(connector);
                Busy--;
                EnsurePruningTimerState();
                Contract.Assert(Idle.Count <= _max);
            }
        }
예제 #2
0
        internal void Release(NpgsqlConnector connector)
        {
            // If Clear/ClearAll has been been called since this connector was first opened,
            // throw it away.
            if (connector.ClearCounter < _clearCounter)
            {
                try
                {
                    connector.Close();
                }
                catch (Exception e)
                {
                    Log.Warn("Exception while closing outdated connector", e, connector.Id);
                }

                lock (this)
                    DecrementBusy();
                Counters.SoftDisconnectsPerSecond.Increment();
                Counters.NumberOfPooledConnections.Decrement();
                return;
            }

            if (connector.IsBroken)
            {
                lock (this)
                    DecrementBusy();
                Counters.NumberOfPooledConnections.Decrement();
                return;
            }

            connector.Reset();
            lock (this)
            {
                // If there are any pending open attempts in progress hand the connector off to
                // them directly.
                while (_waiting.Count > 0)
                {
                    var waitingOpenAttempt = _waiting.Dequeue();
                    var tcs = waitingOpenAttempt.TaskCompletionSource;
                    // Some attempts may be in the queue but in cancelled state, since they've already timed out.
                    // Simply dequeue these and move on.
                    if (tcs.Task.IsCanceled)
                    {
                        continue;
                    }

                    // We have a pending open attempt. "Complete" it, handing off the connector.
                    if (waitingOpenAttempt.IsAsync)
                    {
                        // If the waiting open attempt is asynchronous (i.e. OpenAsync()), we can't simply
                        // call SetResult on its TaskCompletionSource, since it would execute the open's
                        // continuation in our thread (the closing thread). Instead we schedule the completion
                        // to run in the TP

                        // We copy tcs2 and especially connector2 to avoid allocations caused by the closure, see
                        // http://stackoverflow.com/questions/41507166/closure-heap-allocation-happening-at-start-of-method
                        var tcs2       = tcs;
                        var connector2 = connector;

                        Task.Run(() =>
                        {
                            if (!tcs2.TrySetResult(connector2))
                            {
                                // Race condition: the waiter timed out between our IsCanceled check above and here
                                // Recursively call Release again, this will dequeue another open attempt and retry.
                                Debug.Assert(tcs2.Task.IsCanceled);
                                Release(connector2);
                            }
                        });
                    }
                    else
                    {
                        tcs.SetResult(connector);
                    }
                    return;
                }

                Idle.Push(connector);
                DecrementBusy();
                EnsurePruningTimerState();
                Debug.Assert(Idle.Count <= _max);
            }
        }
예제 #3
0
        internal void Release(NpgsqlConnector connector)
        {
            // If Clear/ClearAll has been been called since this connector was first opened,
            // throw it away.
            if (connector.ClearCounter < _clearCounter)
            {
                try
                {
                    connector.Close();
                }
                catch (Exception e)
                {
                    Log.Warn("Exception while closing outdated connector", e, connector.Id);
                }

                lock (this)
                    Busy--;
                return;
            }

            if (connector.IsBroken)
            {
                lock (this)
                    Busy--;
                return;
            }

            connector.Reset();
            lock (this)
            {
                // If there are any pending open attempts in progress hand the connector off to
                // them directly.
                while (Waiting.Count > 0)
                {
                    var waitingOpenAttempt = Waiting.Dequeue();
                    var tcs = waitingOpenAttempt.TaskCompletionSource;
                    // Some attempts may be in the queue but in cancelled state, since they've already timed out.
                    // Simply dequeue these and move on.
                    if (tcs.Task.IsCanceled)
                    {
                        continue;
                    }
                    // We have a pending open attempt. "Complete" it, handing off the connector.
                    if (waitingOpenAttempt.IsAsync)
                    {
                        // If the waiting open attempt is asynchronous (i.e. OpenAsync()), we can't simply
                        // call SetResult on its TaskCompletionSource, since it would execute the open's
                        // continuation in our thread (the closing thread). Instead we schedule the completion
                        // to run in the TP
                        Task.Run(() => tcs.SetResult(connector));
                    }
                    else
                    {
                        tcs.SetResult(connector);
                    }
                    return;
                }

                Idle.Push(connector);
                Busy--;
                EnsurePruningTimerState();
                Contract.Assert(Idle.Count <= _max);
            }
        }