Index: /trunk/src/VBox/Main/ConsoleImplTeleporter.cpp
===================================================================
--- /trunk/src/VBox/Main/ConsoleImplTeleporter.cpp	(revision 31253)
+++ /trunk/src/VBox/Main/ConsoleImplTeleporter.cpp	(revision 31254)
@@ -40,4 +40,5 @@
 #include <VBox/com/string.h>
 #include "VBox/com/ErrorInfo.h"
+
 
 /*******************************************************************************
@@ -288,6 +289,4 @@
 {
     int vrc = RTTcpSgWriteL(pState->mhSocket, 2, pszCommand, strlen(pszCommand), "\n", sizeof("\n") - 1);
-    if (RT_SUCCESS(vrc))
-        vrc = RTTcpFlush(pState->mhSocket);
     if (RT_FAILURE(vrc))
         return setError(E_FAIL, tr("Failed writing command '%s': %Rrc"), pszCommand, vrc);
@@ -529,6 +528,4 @@
         EofHdr.cb       = fCanceled ? UINT32_MAX : 0;
         int rc = RTTcpWrite(pState->mhSocket, &EofHdr, sizeof(EofHdr));
-        if (RT_SUCCESS(rc))
-            rc = RTTcpFlush(pState->mhSocket);
         if (RT_FAILURE(rc))
         {
@@ -540,5 +537,4 @@
     {
         ASMAtomicWriteBool(&pState->mfStopReading, true);
-        RTTcpFlush(pState->mhSocket);
     }
 
@@ -639,5 +635,5 @@
 
     /*
-     * Try connect to the destination machine.
+     * Try connect to the destination machine, disable Nagel.
      * (Note. The caller cleans up mhSocket, so we can return without worries.)
      */
@@ -646,4 +642,6 @@
         return setError(E_FAIL, tr("Failed to connect to port %u on '%s': %Rrc"),
                         pState->muPort, pState->mstrHostname.c_str(), vrc);
+    vrc = RTTcpSetSendCoalescing(pState->mhSocket, false /*fEnable*/);
+    AssertRC(vrc);
 
     /* Read and check the welcome message. */
@@ -1197,5 +1195,4 @@
             teleporterTrgUnlockMedia(pState);
     }
-    RTTcpFlush(pState->mhSocket);
     return rc;
 }
@@ -1224,5 +1221,4 @@
     if (RT_FAILURE(rc))
         LogRel(("Teleporter: RTTcpWrite(,%s,%zu) -> %Rrc\n", szMsg, cch, rc));
-    RTTcpFlush(pState->mhSocket);
     return rc;
 }