chrome/browser/chrome_browser_field_trials_mobile.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chrome/browser/chrome_browser_field_trials_mobile.h"
   6
   7 #include <string>
   8
   9 #include "base/command_line.h"
  10 #include "base/metrics/field_trial.h"
  11 #include "base/prefs/pref_service.h"
  12 #include "base/tracked_objects.h"
  13 #include "chrome/common/chrome_switches.h"
  14 #include "chrome/common/chrome_version_info.h"
  15
  16 #if defined(OS_ANDROID)
  17 #include "chrome/browser/prerender/prerender_field_trial.h"
  18 #endif
  19
  20 namespace chrome {
  21
  22 namespace {
  23
  24 // Base function used by all data reduction proxy field trials. A trial is
  25 // only conducted for installs that are in the "Enabled" group. They are always
  26 // enabled on DEV and BETA channels, and for STABLE, a percentage will be
  27 // controlled from the server. Until the percentage is learned from the server,
  28 // a client-side configuration is used.
  29 void DataCompressionProxyBaseFieldTrial(
  30     const char* trial_name,
  31     const base::FieldTrial::Probability enabled_group_probability,
  32     const base::FieldTrial::Probability total_probability) {
  33   const char kEnabled[] = "Enabled";
  34   const char kDisabled[] = "Disabled";
  35
  36   // Find out if this is a stable channel.
  37   const bool kIsStableChannel =
  38       chrome::VersionInfo::GetChannel() == chrome::VersionInfo::CHANNEL_STABLE;
  39
  40   // Experiment enabled until Jan 1, 2015. By default, disabled.
  41   scoped_refptr<base::FieldTrial> trial(
  42       base::FieldTrialList::FactoryGetFieldTrial(
  43           trial_name,
  44           total_probability,
  45           kDisabled, 2015, 1, 1, base::FieldTrial::ONE_TIME_RANDOMIZED, NULL));
  46
  47   // Non-stable channels will run with probability 1.
  48   trial->AppendGroup(
  49       kEnabled,
  50       kIsStableChannel ? enabled_group_probability : total_probability);
  51
  52   trial->group();
  53 }
  54
  55 void SetupDataCompressionProxyFieldTrials() {
  56   // Governs the rollout of the _promo_ for the compression proxy
  57   // independently from the rollout of compression proxy. The enabled
  58   // percentage is configured to be 10% = 100 / 1000 until overridden by the
  59   // server. When this trial is "Enabled," users get a promo, whereas
  60   // otherwise, compression is available without a promo.
  61   DataCompressionProxyBaseFieldTrial(
  62       "DataCompressionProxyPromoVisibility", 100, 1000);
  63 }
  64
  65 }  // namespace
  66
  67 void SetupMobileFieldTrials(const CommandLine& parsed_command_line) {
  68   SetupDataCompressionProxyFieldTrials();
  69 #if defined(OS_ANDROID)
  70   prerender::ConfigurePrerender(parsed_command_line);
  71
  72   // Force-enable profiler timing depending on the field trial.
  73   if (base::FieldTrialList::FindFullName("ProfilerTiming") == "Enable")
  74     tracked_objects::ThreadData::EnableProfilerTiming();
  75 #endif
  76 }
  77
  78 }  // namespace chrome