better exit pad size

include/llarp/messages/transfer_traffic.hpp

@@ -9,6 +9,7 @@ namespace llarp
 {
   namespace routing
   {
+    constexpr size_t ExitPadSize = 768;
     constexpr size_t MaxExitMTU = 1500;
     struct TransferTrafficMessage final : public IMessage
     {

llarp/exit/endpoint.cpp

@@ -115,7 +115,7 @@ namespace llarp
           m_DownstreamQueue.emplace_back();
         auto pktbuf = pkt.Buffer();
         auto & msg = m_DownstreamQueue.back();
-        if(msg.Size() + pktbuf.sz > 1024)
+        if(msg.Size() + pktbuf.sz > llarp::routing::ExitPadSize)
         {
           m_DownstreamQueue.emplace_back();
           return m_DownstreamQueue.back().PutBuffer(pktbuf);

llarp/handlers/tun.cpp

@@ -350,7 +350,7 @@ namespace llarp
           if(m_Exit)
           {
             pkt.UpdateIPv4PacketOnDst({0}, pkt.dst());
-            m_Exit->QueueUpstreamTraffic(std::move(pkt), 1024);
+            m_Exit->QueueUpstreamTraffic(std::move(pkt), llarp::routing::ExitPadSize);
           }
           else
             llarp::LogWarn(Name(), " has no endpoint for ", pkt.dst());