Remove code to set the send/receive buffer size on XP.

net/socket/tcp_socket_win.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/socket/tcp_socket.h"
 #include "net/socket/tcp_socket_win.h"
 
 #include <errno.h>
 #include <mstcpip.h>
 
 #include "base/callback_helpers.h"
 #include "base/files/file_util.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/profiler/scoped_tracker.h"
-#include "base/win/windows_version.h"
 #include "net/base/address_list.h"
 #include "net/base/connection_type_histograms.h"
 #include "net/base/io_buffer.h"
 #include "net/base/ip_endpoint.h"
 #include "net/base/net_errors.h"
 #include "net/base/network_activity_monitor.h"
 #include "net/base/network_change_notifier.h"
 #include "net/base/sockaddr_storage.h"
 #include "net/base/winsock_init.h"
 #include "net/base/winsock_util.h"
@@ skipping 546 matching lines @@
     return ERR_SOCKET_NOT_CONNECTED;
   *address = *peer_address_;
   return OK;
 }
 
 int TCPSocketWin::SetDefaultOptionsForServer() {
   return SetExclusiveAddrUse();
 }
 
 void TCPSocketWin::SetDefaultOptionsForClient() {
-  // Increase the socket buffer sizes from the default sizes for WinXP.  In
-  // performance testing, there is substantial benefit by increasing from 8KB
-  // to 64KB.
-  // See also:
-  //    http://support.microsoft.com/kb/823764/EN-US
-  // On Vista, if we manually set these sizes, Vista turns off its receive
-  // window auto-tuning feature.
-  //    http://blogs.msdn.com/wndp/archive/2006/05/05/Winhec-blog-tcpip-2.aspx
-  // Since Vista's auto-tune is better than any static value we can could set,
-  // only change these on pre-vista machines.
-  if (base::win::GetVersion() < base::win::VERSION_VISTA) {
-    const int32_t kSocketBufferSize = 64 * 1024;
-    SetSocketReceiveBufferSize(socket_, kSocketBufferSize);
-    SetSocketSendBufferSize(socket_, kSocketBufferSize);
-  }
-
   DisableNagle(socket_, true);
   SetTCPKeepAlive(socket_, true, kTCPKeepAliveSeconds);
 }
 
 int TCPSocketWin::SetExclusiveAddrUse() {
   // On Windows, a bound end point can be hijacked by another process by
   // setting SO_REUSEADDR. Therefore a Windows-only option SO_EXCLUSIVEADDRUSE
   // was introduced in Windows NT 4.0 SP4. If the socket that is bound to the
   // end point has SO_EXCLUSIVEADDRUSE enabled, it is not possible for another
   // socket to forcibly bind to the end point until the end point is unbound.
@@ skipping 442 matching lines @@
 }
 
 bool TCPSocketWin::GetEstimatedRoundTripTime(base::TimeDelta* out_rtt) const {
   DCHECK(out_rtt);
   // TODO(bmcquade): Consider implementing using
   // GetPerTcpConnectionEStats/GetPerTcp6ConnectionEStats.
   return false;
 }
 
 }  // namespace net