Bug 1135104 - increase send window on modern windows r=dragana

modules/libpref/init/all.js

@@ -4365,10 +4365,11 @@ pref("gfx.gralloc.fence-with-readpixels", false);
 pref("stagefright.force-enabled", false);
 pref("stagefright.disabled", false);
 
-#ifdef XP_WIN
-// The default TCP send window on Windows is too small, and autotuning only occurs on receive
-pref("network.tcp.sendbuffer", 131072);
-#endif
+// sendbuffer of 0 means use OS default, sendbuffer unset means use
+// gecko default which varies depending on windows version and is OS
+// default on non windows
+// pref("network.tcp.sendbuffer", 0);
+
 // TCP Keepalive
 pref("network.tcp.keepalive.enabled", true);
 // Default idle time before first TCP keepalive probe; same time for interval

netwerk/base/nsSocketTransportService2.cpp

@@ -27,6 +27,10 @@
 #include "nsIFile.h"
 #include "nsIWidget.h"
 
+#if defined(XP_WIN)
+#include "mozilla/WindowsVersion.h"
+#endif
+
 using namespace mozilla;
 using namespace mozilla::net;
 
@@ -1178,6 +1182,28 @@ nsSocketTransportService::DoPollIteration(TimeDuration *pollDuration)
     return NS_OK;
 }
 
+void
+nsSocketTransportService::UpdateSendBufferPref(nsIPrefBranch *pref)
+{
+    int32_t bufferSize;
+
+    // If the pref is set, honor it. 0 means use OS defaults.
+    nsresult rv = pref->GetIntPref(SEND_BUFFER_PREF, &bufferSize);
+    if (NS_SUCCEEDED(rv)) {
+        mSendBufferSize = bufferSize;
+        return;
+    }
+
+#if defined(XP_WIN)
+    // If the pref is not set but this is windows set it depending on windows version
+    if (!mozilla::IsWin2003OrLater()) { // windows xp
+        mSendBufferSize = 131072;
+    } else { // vista or later
+        mSendBufferSize = 131072 * 4;
+    }
+#endif
+}
+
 nsresult
 nsSocketTransportService::UpdatePrefs()
 {
@@ -1185,14 +1211,11 @@ nsSocketTransportService::UpdatePrefs()
 
     nsCOMPtr<nsIPrefBranch> tmpPrefService = do_GetService(NS_PREFSERVICE_CONTRACTID);
     if (tmpPrefService) {
-        int32_t bufferSize;
-        nsresult rv = tmpPrefService->GetIntPref(SEND_BUFFER_PREF, &bufferSize);
-        if (NS_SUCCEEDED(rv) && bufferSize > 0)
-            mSendBufferSize = bufferSize;
+        UpdateSendBufferPref(tmpPrefService);
 
         // Default TCP Keepalive Values.
         int32_t keepaliveIdleTimeS;
-        rv = tmpPrefService->GetIntPref(KEEPALIVE_IDLE_TIME_PREF,
+        nsresult rv = tmpPrefService->GetIntPref(KEEPALIVE_IDLE_TIME_PREF,
                                         &keepaliveIdleTimeS);
         if (NS_SUCCEEDED(rv))
             mKeepaliveIdleTimeS = clamped(keepaliveIdleTimeS,

netwerk/base/nsSocketTransportService2.h

@@ -25,6 +25,7 @@
 
 class nsASocketHandler;
 struct PRPollDesc;
+class nsIPrefBranch;
 
 //-----------------------------------------------------------------------------
 
@@ -210,6 +211,7 @@ private:
 
     // Preference Monitor for SendBufferSize and Keepalive prefs.
     nsresult    UpdatePrefs();
+    void        UpdateSendBufferPref(nsIPrefBranch *);
     int32_t     mSendBufferSize;
     // Number of seconds of connection is idle before first keepalive ping.
     int32_t     mKeepaliveIdleTimeS;