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 "chrome/common/chrome_switches.h"
  13 #include "chrome/common/chrome_version_info.h"
  14
  15 #if defined(OS_ANDROID)
  16 #include "chrome/browser/prerender/prerender_field_trial.h"
  17 #endif
  18
  19 namespace chrome {
  20
  21 namespace {
  22
  23 // Base function used by all data reduction proxy field trials. A trial is
  24 // only conducted for installs that are in the "Enabled" group. They are always
  25 // enabled on DEV and BETA channels, and for STABLE, a percentage will be
  26 // controlled from the server. Until the percentage is learned from the server,
  27 // a client-side configuration is used.
  28 void DataCompressionProxyBaseFieldTrial(
  29     const char* trial_name,
  30     const base::FieldTrial::Probability enabled_group_probability,
  31     const base::FieldTrial::Probability total_probability) {
  32   const char kEnabled[] = "Enabled";
  33   const char kDisabled[] = "Disabled";
  34
  35   // Find out if this is a stable channel.
  36   const bool kIsStableChannel =
  37       chrome::VersionInfo::GetChannel() == chrome::VersionInfo::CHANNEL_STABLE;
  38
  39   // Experiment enabled until Jan 1, 2015. By default, disabled.
  40   scoped_refptr<base::FieldTrial> trial(
  41       base::FieldTrialList::FactoryGetFieldTrial(
  42           trial_name,
  43           total_probability,
  44           kDisabled, 2015, 1, 1, base::FieldTrial::ONE_TIME_RANDOMIZED, NULL));
  45
  46   // Non-stable channels will run with probability 1.
  47   const int kEnabledGroup = trial->AppendGroup(
  48       kEnabled,
  49       kIsStableChannel ? enabled_group_probability : total_probability);
  50
  51   const int v = trial->group();
  52   VLOG(1) << trial_name <<  " enabled group id: " << kEnabledGroup
  53           << ". Selected group id: " << v;
  54 }
  55
  56 void DataCompressionProxyFieldTrials() {
  57   // Governs the rollout of the compression proxy for Chrome on mobile
  58   // platforms. In all channels, the percentage will be controlled from the
  59   // server, and is configured to be 100% = 1000 / 1000 until overridden by the
  60   // server.
  61   DataCompressionProxyBaseFieldTrial(
  62       "DataCompressionProxyRollout", 1000, 1000);
  63
  64   // Governs the rollout of the _promo_ for the compression proxy
  65   // independently from the rollout of compression proxy. The enabled
  66   // percentage is configured to be 10% = 100 / 1000 until overridden by the
  67   // server. When this trial is "Enabled," users get a promo, whereas
  68   // otherwise, compression is available without a promo.
  69   DataCompressionProxyBaseFieldTrial(
  70       "DataCompressionProxyPromoVisibility", 100, 1000);
  71 }
  72
  73 }  // namespace
  74
  75 void SetupMobileFieldTrials(const CommandLine& parsed_command_line) {
  76   DataCompressionProxyFieldTrials();
  77 #if defined(OS_ANDROID)
  78   prerender::ConfigurePrerender(parsed_command_line);
  79 #endif
  80 }
  81
  82 }  // namespace chrome