ns3: manually packetize the data to send

diff --git a/src/surf/ns3/ns3_simulator.cpp b/src/surf/ns3/ns3_simulator.cpp
index 825e555..64230a0 100644 (file)
--- a/src/surf/ns3/ns3_simulator.cpp
+++ b/src/surf/ns3/ns3_simulator.cpp
@@ -57,7 +57,8 @@ static void send_cb(ns3::Ptr<ns3::Socket> sock, uint32_t txSpace)
   /* While not all is buffered and there remain space in the buffers */
   while (flow->bufferedBytes_ < flow->totalBytes_ && sock->GetTxAvailable() > 0) {
 
-    uint32_t toWrite = std::min({flow->remaining_, sock->GetTxAvailable()});
+    // Send at most 1040 bytes (data size in a TCP packet), as NS3 seems to not split correctly by itself
+    uint32_t toWrite = std::min({flow->remaining_, sock->GetTxAvailable(), std::uint32_t(1040)});
     if (toWrite == 0) { // buffer full
       XBT_DEBUG("%f: buffer full on flow %p (still %u to go)", ns3::Simulator::Now().GetSeconds(), flow,
                 flow->remaining_);