commit 479fea3ba5c4a7733402efbecda788af75ff2e79
author ianswett <ianswett@google.com> Wed Sep 04 02:51:01 2019 -0700
committer Copybara-Service <copybara-worker@google.com> Thu Sep 05 11:19:46 2019 -0700
tree 035cef2e8a490177614436c84094ac2e0314c946
parent b7e6e6468c7ca365bf85652f443406392754cd09

gfe-relnote: Save the time the last inflight packet was sent instead of iterating through the deque.  Protected by gfe2_reloadable_flag_quic_simple_inflight_time.

PiperOrigin-RevId: 267115183
Change-Id: I98661c317b4009e182ecbec9e25c8fd368791758

quic/core/quic_sent_packet_manager.cc

diff --git a/quic/core/quic_sent_packet_manager.cc b/quic/core/quic_sent_packet_manager.cc
index 2eb606b..54e6444 100644
--- a/quic/core/quic_sent_packet_manager.cc
+++ b/quic/core/quic_sent_packet_manager.cc
@@ -645,7 +645,7 @@
     // Other crypto handshake packets won't be in flight, only the newest
     // transmission of a crypto packet is in flight at once.
     // TODO(ianswett): Instead of handling all crypto packets special,
-    // only handle nullptr encrypted packets in a special way.
+    // only handle null encrypted packets in a special way.
     const QuicTransmissionInfo& newest_transmission_info =
         unacked_packets_.GetTransmissionInfo(newest_transmission);
     unacked_packets_.NotifyFramesAcked(newest_transmission_info, ack_delay_time,
@@ -1021,7 +1021,8 @@
       // TODO(ianswett): When CWND is available, it would be preferable to
       // set the timer based on the earliest retransmittable packet.
       // Base the updated timer on the send time of the last packet.
-      const QuicTime sent_time = unacked_packets_.GetLastPacketSentTime();
+      const QuicTime sent_time =
+          unacked_packets_.GetLastInFlightPacketSentTime();
       const QuicTime tlp_time = sent_time + GetTailLossProbeDelay();
       // Ensure the TLP timer never gets set to a time in the past.
       return std::max(clock_->ApproximateNow(), tlp_time);
@@ -1029,15 +1030,16 @@
     case RTO_MODE: {
       DCHECK(!pto_enabled_);
       // The RTO is based on the first outstanding packet.
-      const QuicTime sent_time = unacked_packets_.GetLastPacketSentTime();
+      const QuicTime sent_time =
+          unacked_packets_.GetLastInFlightPacketSentTime();
       QuicTime rto_time = sent_time + GetRetransmissionDelay();
       // Wait for TLP packets to be acked before an RTO fires.
-      QuicTime tlp_time =
-          unacked_packets_.GetLastPacketSentTime() + GetTailLossProbeDelay();
+      QuicTime tlp_time = sent_time + GetTailLossProbeDelay();
       return std::max(tlp_time, rto_time);
     }
     case PTO_MODE: {
-      if (handshake_mode_disabled_ && !handshake_confirmed_ &&
+      if (!unacked_packets().simple_inflight_time() &&
+          handshake_mode_disabled_ && !handshake_confirmed_ &&
           !unacked_packets_.HasInFlightPackets()) {
         DCHECK_EQ(Perspective::IS_CLIENT, unacked_packets_.perspective());
         return std::max(clock_->ApproximateNow(),
@@ -1045,9 +1047,9 @@
                             GetProbeTimeoutDelay());
       }
       // Ensure PTO never gets set to a time in the past.
-      return std::max(
-          clock_->ApproximateNow(),
-          unacked_packets_.GetLastPacketSentTime() + GetProbeTimeoutDelay());
+      return std::max(clock_->ApproximateNow(),
+                      unacked_packets_.GetLastInFlightPacketSentTime() +
+                          GetProbeTimeoutDelay());
     }
   }
   DCHECK(false);