Stop processing messages on full send buffer and dont disconnect.

Also decrease default send/receive buffer sizes from 10 to 5 mb
as this patch makes it easy for a node to fill both instead of
only send.

src/init.cpp

@@ -238,8 +238,8 @@ std::string HelpMessage()
         "  -dnsseed               " + _("Find peers using DNS lookup (default: 1 unless -connect)") + "\n" +
         "  -banscore=<n>          " + _("Threshold for disconnecting misbehaving peers (default: 100)") + "\n" +
         "  -bantime=<n>           " + _("Number of seconds to keep misbehaving peers from reconnecting (default: 86400)") + "\n" +
-        "  -maxreceivebuffer=<n>  " + _("Maximum per-connection receive buffer, <n>*1000 bytes (default: 10000)") + "\n" +
+        "  -maxreceivebuffer=<n>  " + _("Maximum per-connection receive buffer, <n>*1000 bytes (default: 5000)") + "\n" +
-        "  -maxsendbuffer=<n>     " + _("Maximum per-connection send buffer, <n>*1000 bytes (default: 10000)") + "\n" +
+        "  -maxsendbuffer=<n>     " + _("Maximum per-connection send buffer, <n>*1000 bytes (default: 5000)") + "\n" +
 #ifdef USE_UPNP
 #if USE_UPNP
         "  -upnp                  " + _("Use UPnP to map the listening port (default: 1 when listening)") + "\n" +

src/main.cpp

@@ -2632,25 +2632,21 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv)
         // Send the rest of the chain
         if (pindex)
             pindex = pindex->pnext;
-        int nLimit = 500 + locator.GetDistanceBack();
+        int nLimit = 500;
-        unsigned int nBytes = 0;
         printf("getblocks %d to %s limit %d\n", (pindex ? pindex->nHeight : -1), hashStop.ToString().substr(0,20).c_str(), nLimit);
         for (; pindex; pindex = pindex->pnext)
         {
             if (pindex->GetBlockHash() == hashStop)
             {
-                printf("  getblocks stopping at %d %s (%u bytes)\n", pindex->nHeight, pindex->GetBlockHash().ToString().substr(0,20).c_str(), nBytes);
+                printf("  getblocks stopping at %d %s\n", pindex->nHeight, pindex->GetBlockHash().ToString().substr(0,20).c_str());
                 break;
             }
             pfrom->PushInventory(CInv(MSG_BLOCK, pindex->GetBlockHash()));
-            CBlock block;
+            if (--nLimit <= 0)
-            block.ReadFromDisk(pindex, true);
-            nBytes += block.GetSerializeSize(SER_NETWORK, PROTOCOL_VERSION);
-            if (--nLimit <= 0 || nBytes >= SendBufferSize()/2)
             {
                 // When this block is requested, we'll send an inv that'll make them
                 // getblocks the next batch of inventory.
-                printf("  getblocks stopping at limit %d %s (%u bytes)\n", pindex->nHeight, pindex->GetBlockHash().ToString().substr(0,20).c_str(), nBytes);
+                printf("  getblocks stopping at limit %d %s\n", pindex->nHeight, pindex->GetBlockHash().ToString().substr(0,20).c_str());
                 pfrom->hashContinue = pindex->GetBlockHash();
                 break;
             }
@@ -2910,6 +2906,10 @@ bool ProcessMessages(CNode* pfrom)
 
     loop
     {
+        // Don't bother if send buffer is too full to respond anyway
+        if (pfrom->vSend.size() >= SendBufferSize())
+            break;
+
         // Scan for message start
         CDataStream::iterator pstart = search(vRecv.begin(), vRecv.end(), BEGIN(pchMessageStart), END(pchMessageStart));
         int nHeaderSize = vRecv.GetSerializeSize(CMessageHeader());

src/net.cpp

@@ -922,11 +922,8 @@ void ThreadSocketHandler2(void* parg)
                                 pnode->CloseSocketDisconnect();
                             }
                         }
-                        if (vSend.size() > SendBufferSize()) {
+                        if (vSend.size() > SendBufferSize())
-                            if (!pnode->fDisconnect)
+                            printf("socket send buffer full warning (%d bytes)\n", vSend.size());
-                                printf("socket send flood control disconnect (%d bytes)\n", vSend.size());
-                            pnode->CloseSocketDisconnect();
-                        }
                     }
                 }
             }

src/net.h

@@ -26,8 +26,8 @@ extern int nBestHeight;
 
 
 
-inline unsigned int ReceiveBufferSize() { return 1000*GetArg("-maxreceivebuffer", 10*1000); }
+inline unsigned int ReceiveBufferSize() { return 1000*GetArg("-maxreceivebuffer", 5*1000); }
-inline unsigned int SendBufferSize() { return 1000*GetArg("-maxsendbuffer", 10*1000); }
+inline unsigned int SendBufferSize() { return 1000*GetArg("-maxsendbuffer", 5*1000); }
 
 void AddOneShot(std::string strDest);
 bool RecvLine(SOCKET hSocket, std::string& strLine);