Deciding best connection to schedule requests on based on cwnd and idle time

net/socket/tcp_client_socket_win.h

 // Copyright (c) 2011 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.
 
 #ifndef NET_SOCKET_TCP_CLIENT_SOCKET_WIN_H_
 #define NET_SOCKET_TCP_CLIENT_SOCKET_WIN_H_
 #pragma once
 
 #include <winsock2.h>
 
 #include "base/scoped_ptr.h"
+#include "base/time.h"
 #include "base/threading/non_thread_safe.h"
 #include "net/base/address_list.h"
 #include "net/base/completion_callback.h"
 #include "net/base/net_log.h"
 #include "net/socket/stream_socket.h"
 
 namespace net {
 
 class BoundNetLog;
 
@@ skipping 25 matching lines @@
   virtual bool IsConnected() const;
   virtual bool IsConnectedAndIdle() const;
   virtual int GetPeerAddress(AddressList* address) const;
   virtual int GetLocalAddress(IPEndPoint* address) const;
   virtual const BoundNetLog& NetLog() const { return net_log_; }
   virtual void SetSubresourceSpeculation();
   virtual void SetOmniboxSpeculation();
   virtual bool WasEverUsed() const;
   virtual bool UsingTCPFastOpen() const;
 
+  virtual int64 NumBytesRead() const { return num_bytes_read_; }
+  virtual double GetRTTInMs() const { return rtt_ms_; }

[Mike Belshe, 2011/06/09 16:08:52]

Nit:  I like that you are exposing this function off the socket, but it's not
really RTT.  It's ConnectTime().  Can we change the name of this method to
reflect that?  It's okay in other parts of the code to use ConnectTime() as an
approximation for RTT, but it is simply not true that this is the RTT.

[Gagan, 2011/06/09 19:49:26]

Done.

+
   // Socket methods:
   // Multiple outstanding requests are not supported.
   // Full duplex mode (reading and writing at the same time) is supported
   virtual int Read(IOBuffer* buf, int buf_len, CompletionCallback* callback);
   virtual int Write(IOBuffer* buf, int buf_len, CompletionCallback* callback);
 
   virtual bool SetReceiveBufferSize(int32 size);
   virtual bool SetSendBufferSize(int32 size);
 
  private:
@@ skipping 67 matching lines @@
 
   BoundNetLog net_log_;
 
   // This socket was previously disconnected and has not been re-connected.
   bool previously_disconnected_;
 
   // Record of connectivity and transmissions, for use in speculative connection
   // histograms.
   UseHistory use_history_;
 
+  base::Time connect_start_time_;
+  int64 num_bytes_read_;
+  double rtt_ms_;
+
   DISALLOW_COPY_AND_ASSIGN(TCPClientSocketWin);
 };
 
 }  // namespace net
 
 #endif  // NET_SOCKET_TCP_CLIENT_SOCKET_WIN_H_