Clean up alwaysPTOMultiple

Summary: No longer needed

Reviewed By: kvtsoy

Differential Revision: D64730204

fbshipit-source-id: 260e07f82bb8699d7aa94c0e2eaf727828a6d5e8

quic/loss/QuicLossFunctions.cpp

@@ -100,13 +100,6 @@ void onPTOAlarm(QuicConnectionStateBase& conn) {
           packetCount[PacketNumberSpace::AppData];
     }
   }
-  if (conn.transportSettings.alwaysPtoMultiple) {
-    for (auto& numProbes : numProbePackets) {
-      if (numProbes > 0) {
-        numProbes = kPacketToSendForPTO;
-      }
-    }
-  }
 }
 
 template <class T, size_t N>

quic/loss/test/QuicLossFunctionsTest.cpp

@@ -1325,33 +1325,6 @@ TEST_F(QuicLossFunctionsTest, PTOAvoidPointless) {
   EXPECT_EQ(conn->pendingEvents.numProbePackets[PacketNumberSpace::AppData], 1);
 }
 
-TEST_F(QuicLossFunctionsTest, PTOAlwaysSendTwo) {
-  // If there is no lost data and the outstanding data is less than the
-  // kPacketToSendForPTO packets, send only the available outstanding count.
-  auto conn = createConn();
-  conn->transportSettings.alwaysPtoMultiple = true;
-
-  conn->initialWriteCipher = createNoOpAead();
-  conn->initialHeaderCipher = createNoOpHeaderCipher();
-
-  conn->handshakeWriteCipher = createNoOpAead();
-  conn->handshakeWriteHeaderCipher = createNoOpHeaderCipher();
-
-  conn->oneRttWriteCipher = createNoOpAead();
-  conn->oneRttWriteHeaderCipher = createNoOpHeaderCipher();
-
-  conn->outstandings.packetCount[PacketNumberSpace::Initial] = 1;
-  conn->outstandings.packetCount[PacketNumberSpace::Handshake] = 1;
-  conn->outstandings.packetCount[PacketNumberSpace::AppData] = 1;
-
-  onPTOAlarm(*conn);
-
-  EXPECT_EQ(conn->pendingEvents.numProbePackets[PacketNumberSpace::Initial], 2);
-  EXPECT_EQ(
-      conn->pendingEvents.numProbePackets[PacketNumberSpace::Handshake], 2);
-  EXPECT_EQ(conn->pendingEvents.numProbePackets[PacketNumberSpace::AppData], 2);
-}
-
 TEST_F(QuicLossFunctionsTest, EmptyOutstandingNoTimeout) {
   auto conn = createConn();
   EXPECT_CALL(timeout, cancelLossTimeout()).Times(1);

quic/state/TransportSettings.h

@@ -410,8 +410,6 @@ struct TransportSettings {
   // receiving and then processing.
   bool networkDataPerSocketRead{false};
   bool cloneAllPacketsWithCryptoFrame{false};
-  // Always send multiple PTOs even if we don't have multiple packets.
-  bool alwaysPtoMultiple{false};
   // Use a reordering threshold heuristic of inflight / 2.
   bool useInflightReorderingThreshold{false};
   // Raise read callbacks for all unidirectional streams first on data