QUIC - disable QUIC if packet loss rate is bad for a connection.

net/quic/quic_client_session.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/quic/quic_client_session.h"
 
 #include "base/callback_helpers.h"
 #include "base/message_loop/message_loop.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/sparse_histogram.h"
@@ skipping 575 matching lines @@
     stream_requests_.pop_front();
     request->OnRequestCompleteSuccess(CreateOutgoingReliableStreamImpl());
   }
 
   if (GetNumOpenStreams() == 0) {
     stream_factory_->OnIdleSession(this);
   }
 }
 
 void QuicClientSession::OnCryptoHandshakeEvent(CryptoHandshakeEvent event) {
+  if (stream_factory_ && event == HANDSHAKE_CONFIRMED) {
+    float packet_loss_rate = logger_->PacketLossRate() / 10;

[Ryan Hamilton, 2015/03/23 02:31:06]

Why / 10?

[ramant (doing other things), 2015/03/24 03:07:22]

Remove the percent. Used fraction.

+    if (packet_loss_rate > stream_factory_->packet_loss_threshold()) {
+      stream_factory_->OnBadPacketLoss(server_id_);

[Ryan Hamilton, 2015/03/23 02:31:06]

I wonder if it might make more sense for this to be in the factory instead of
the session since it looks like the factory knows the loss threshold.

[ramant (doing other things), 2015/03/24 03:07:22]

Done.

+      // We abandon the connection if packet loss rate is too bad.
+      DVLOG(1) << "Closing session on bad packet loss rate: "
+               << packet_loss_rate;
+      UMA_HISTOGRAM_BOOLEAN("Net.QuicSession.HasBadPacketLossRate", true);
+      NotifyFactoryOfSessionGoingAway();
+      CloseSessionOnErrorInner(ERR_ABORTED, QUIC_BAD_PACKET_LOSS_RATE);
+      NotifyFactoryOfSessionClosedLater();

[Ryan Hamilton, 2015/03/23 02:31:06]

Is there a method the factory could call which would do all of this? Maybe
CloseSessionOnError?

[ramant (doing other things), 2015/03/24 03:07:22]

Called CloseSessionOnError from QuicStreamFactory.

Done.

+      return;
+    }
+  }
+
   if (!callback_.is_null() &&
       (!require_confirmation_ ||
        event == HANDSHAKE_CONFIRMED || event == ENCRYPTION_REESTABLISHED)) {
     // TODO(rtenneti): Currently for all CryptoHandshakeEvent events, callback_
     // could be called because there are no error events in CryptoHandshakeEvent
     // enum. If error events are added to CryptoHandshakeEvent, then the
     // following code needs to changed.
     base::ResetAndReturn(&callback_).Run(OK);
   }
   if (event == HANDSHAKE_CONFIRMED) {
@@ skipping 304 matching lines @@
     return;
 
   // TODO(rch): re-enable this code once beta is cut.
   //  if (stream_factory_)
   //    stream_factory_->OnSessionConnectTimeout(this);
   //  CloseAllStreams(ERR_QUIC_HANDSHAKE_FAILED);
   //  DCHECK_EQ(0u, GetNumOpenStreams());
 }
 
 }  // namespace net