Remove experimental code to pick the "warmest" socket

chrome/browser/chrome_browser_field_trials.cc

 // Copyright (c) 2012 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 "chrome/browser/chrome_browser_field_trials.h"
 
 #include <string>
 
 #include "apps/field_trial_names.h"
 #include "apps/pref_names.h"
@@ skipping 12 matching lines @@
 #include "chrome/browser/omnibox/omnibox_field_trial.h"
 #include "chrome/browser/prerender/prerender_field_trial.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/browser/safe_browsing/safe_browsing_blocking_page.h"
 #include "chrome/browser/ui/sync/one_click_signin_helper.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/chrome_version_info.h"
 #include "chrome/common/metrics/variations/uniformity_field_trials.h"
 #include "chrome/common/metrics/variations/variations_util.h"
 #include "chrome/common/pref_names.h"
-#include "net/socket/client_socket_pool_base.h"
 #include "net/spdy/spdy_session.h"
 #include "ui/base/layout.h"
 
 #if defined(OS_WIN)
 #include "net/socket/tcp_client_socket_win.h"
 #endif  // defined(OS_WIN)
 
-namespace {
-
-void SetSocketReusePolicy(int warmest_socket_trial_group,
-                          const int socket_policy[],
-                          int num_groups) {
-  const int* result = std::find(socket_policy, socket_policy + num_groups,
-                                warmest_socket_trial_group);
-  DCHECK_NE(result, socket_policy + num_groups)
-      << "Not a valid socket reuse policy group";
-  net::SetSocketReusePolicy(result - socket_policy);
-}
-
-}  // namespace
-
 ChromeBrowserFieldTrials::ChromeBrowserFieldTrials(
-    const CommandLine& parsed_command_line) :
-        parsed_command_line_(parsed_command_line) {
+    const CommandLine& parsed_command_line)
+    : parsed_command_line_(parsed_command_line) {
 }
 
 ChromeBrowserFieldTrials::~ChromeBrowserFieldTrials() {
 }
 
 void ChromeBrowserFieldTrials::SetupFieldTrials(PrefService* local_state) {
   const base::Time install_time = base::Time::FromTimeT(
       local_state->GetInt64(prefs::kInstallDate));
   DCHECK(!install_time.is_null());
   chrome_variations::SetupUniformityFieldTrials(install_time);
   SetUpSimpleCacheFieldTrial();
 #if !defined(OS_ANDROID)
   SetupDesktopFieldTrials(local_state);
 #endif  // defined(OS_ANDROID)
 }
 
 void ChromeBrowserFieldTrials::SetupDesktopFieldTrials(
     PrefService* local_state) {
   prerender::ConfigurePrefetchAndPrerender(parsed_command_line_);
   SpdyFieldTrial();
-  WarmConnectionFieldTrial();
   AutoLaunchChromeFieldTrial();
   gpu_util::InitializeCompositingFieldTrial();
   OmniboxFieldTrial::ActivateStaticTrials();
   SetUpInfiniteCacheFieldTrial();
   SetUpCacheSensitivityAnalysisFieldTrial();
   DisableShowProfileSwitcherTrialIfNecessary();
   WindowsOverlappedTCPReadsFieldTrial();
 #if defined(ENABLE_ONE_CLICK_SIGNIN)
   OneClickSigninHelper::InitializeFieldTrial();
 #endif
@@ skipping 29 matching lines @@
   scoped_refptr<base::FieldTrial> trial(
       base::FieldTrialList::FactoryGetFieldTrial(
           "SpdyCwnd", kSpdyCwndDivisor, "cwndDynamic", 2013, 6, 30, NULL));
 
   trial->AppendGroup("cwnd10", kSpdyCwnd10);
   trial->AppendGroup("cwnd16", kSpdyCwnd16);
   trial->AppendGroup("cwndMin16", kSpdyCwndMin16);
   trial->AppendGroup("cwndMin10", kSpdyCwndMin10);
 }
 
-// If --socket-reuse-policy is not specified, run an A/B test for choosing the
-// warmest socket.
-void ChromeBrowserFieldTrials::WarmConnectionFieldTrial() {
-  const CommandLine& command_line = parsed_command_line_;
-  if (command_line.HasSwitch(switches::kSocketReusePolicy)) {
-    std::string socket_reuse_policy_str = command_line.GetSwitchValueASCII(
-        switches::kSocketReusePolicy);
-    int policy = -1;
-    base::StringToInt(socket_reuse_policy_str, &policy);
-
-    const int policy_list[] = { 0, 1, 2 };
-    VLOG(1) << "Setting socket_reuse_policy = " << policy;
-    SetSocketReusePolicy(policy, policy_list, arraysize(policy_list));
-    return;
-  }
-
-  const base::FieldTrial::Probability kWarmSocketDivisor = 100;
-  const base::FieldTrial::Probability kWarmSocketProbability = 33;
-
-  // Default value is USE_LAST_ACCESSED_SOCKET.
-  int last_accessed_socket = -1;
-
-  // After January 30, 2013 builds, it will always be in default group.
-  scoped_refptr<base::FieldTrial> warmest_socket_trial(
-      base::FieldTrialList::FactoryGetFieldTrial(
-          "WarmSocketImpact", kWarmSocketDivisor, "last_accessed_socket",
-          2013, 1, 30, &last_accessed_socket));
-
-  const int warmest_socket = warmest_socket_trial->AppendGroup(
-      "warmest_socket", kWarmSocketProbability);
-  const int warm_socket = warmest_socket_trial->AppendGroup(
-      "warm_socket", kWarmSocketProbability);
-
-  const int warmest_socket_trial_group = warmest_socket_trial->group();
-
-  const int policy_list[] = { warmest_socket, warm_socket,
-                              last_accessed_socket };
-  SetSocketReusePolicy(warmest_socket_trial_group, policy_list,
-                       arraysize(policy_list));
-}
-
 void ChromeBrowserFieldTrials::AutoLaunchChromeFieldTrial() {
   std::string brand;
   google_util::GetBrand(&brand);
 
   // Create a 100% field trial based on the brand code.
   if (auto_launch_trial::IsInExperimentGroup(brand)) {
     base::FieldTrialList::CreateFieldTrial(kAutoLaunchTrialName,
                                            kAutoLaunchTrialAutoLaunchGroup);
   } else if (auto_launch_trial::IsInControlGroup(brand)) {
     base::FieldTrialList::CreateFieldTrial(kAutoLaunchTrialName,
@@ skipping 107 matching lines @@
   // Call |FindValue()| on the trials below, which may come from the server, to
   // ensure they get marked as "used" for the purposes of data reporting.
   base::FieldTrialList::FindValue("UMA-Dynamic-Binary-Uniformity-Trial");
   base::FieldTrialList::FindValue("UMA-Dynamic-Uniformity-Trial");
   base::FieldTrialList::FindValue("InstantDummy");
   base::FieldTrialList::FindValue("InstantChannel");
   base::FieldTrialList::FindValue("Test0PercentDefault");
   // Activate the autocomplete dynamic field trials.
   OmniboxFieldTrial::ActivateDynamicTrials();
 }