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

net/http/http_network_transaction.cc

 // 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.
 
 #include "net/http/http_network_transaction.h"
 
 #include <set>
 #include <vector>
 
 #include "base/compiler_specific.h"
@@ skipping 919 matching lines @@
     // TODO(mbelshe): The keepalive property is really a property of
     //    the stream.  No need to compute it here just to pass back
     //    to the stream's Close function.
     if (stream_->CanFindEndOfResponse())
       keep_alive = GetResponseHeaders()->IsKeepAlive();
   }
 
   // Clean up connection if we are done.
   if (done) {
     LogTransactionMetrics();
+    LogRttVsBytesMetrics();
     stream_->Close(!keep_alive);
     // Note: we don't reset the stream here.  We've closed it, but we still
     // need it around so that callers can call methods such as
     // GetUploadProgress() and have them be meaningful.
     // TODO(mbelshe): This means we closed the stream here, and we close it
     // again in ~HttpNetworkTransaction.  Clean that up.
 
     // The next Read call will return 0 (EOF).
   }
 
@@ skipping 126 matching lines @@
                               base::TimeDelta::FromMilliseconds(1),
                               base::TimeDelta::FromMinutes(10), 100);
   if (!stream_->IsConnectionReused()) {
     UMA_HISTOGRAM_CLIPPED_TIMES(
         "Net.Transaction_Latency_Total_New_Connection_Under_10",
         total_duration, base::TimeDelta::FromMilliseconds(1),
         base::TimeDelta::FromMinutes(10), 100);
   }
 }
 
+void HttpNetworkTransaction::LogRttVsBytesMetrics() const {
+  stream_->LogRttVsBytesMetrics();
+}
+
 int HttpNetworkTransaction::HandleCertificateRequest(int error) {
   // There are two paths through which the server can request a certificate
   // from us.  The first is during the initial handshake, the second is
   // during SSL renegotiation.
   //
   // In both cases, we want to close the connection before proceeding.
   // We do this for two reasons:
   //   First, we don't want to keep the connection to the server hung for a
   //   long time while the user selects a certificate.
   //   Second, even if we did keep the connection open, NSS has a bug where
@@ skipping 245 matching lines @@
       description = base::StringPrintf("Unknown state 0x%08X (%u)", state,
                                        state);
       break;
   }
   return description;
 }
 
 #undef STATE_CASE
 
 }  // namespace net