src/components/domain_reliability/scheduler.cc

   1 // Copyright 2014 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 "components/domain_reliability/scheduler.h"
   6
   7 #include <algorithm>
   8
   9 #include "base/metrics/field_trial.h"
  10 #include "base/strings/string_number_conversions.h"
  11 #include "base/values.h"
  12 #include "components/domain_reliability/config.h"
  13 #include "components/domain_reliability/util.h"
  14
  15 namespace {
  16
  17 const unsigned kInvalidCollectorIndex = static_cast<unsigned>(-1);
  18
  19 const unsigned kDefaultMinimumUploadDelaySec = 60;
  20 const unsigned kDefaultMaximumUploadDelaySec = 300;
  21 const unsigned kDefaultUploadRetryIntervalSec = 60;
  22
  23 const char* kMinimumUploadDelayFieldTrialName = "DomRel-MinimumUploadDelay";
  24 const char* kMaximumUploadDelayFieldTrialName = "DomRel-MaximumUploadDelay";
  25 const char* kUploadRetryIntervalFieldTrialName = "DomRel-UploadRetryInterval";
  26
  27 // Fixed elements of backoff policy
  28 const double kMultiplyFactor = 2.0;
  29 const double kJitterFactor = 0.1;
  30 const int64 kMaximumBackoffMs = 60 * 1000 * 1000;
  31
  32 unsigned GetUnsignedFieldTrialValueOrDefault(std::string field_trial_name,
  33                                              unsigned default_value) {
  34   if (!base::FieldTrialList::TrialExists(field_trial_name))
  35     return default_value;
  36
  37   std::string group_name = base::FieldTrialList::FindFullName(field_trial_name);
  38   unsigned value;
  39   if (!base::StringToUint(group_name, &value)) {
  40     LOG(ERROR) << "Expected unsigned integer for field trial "
  41                << field_trial_name << " group name, but got \"" << group_name
  42                << "\".";
  43     return default_value;
  44   }
  45
  46   return value;
  47 }
  48
  49 }  // namespace
  50
  51 namespace domain_reliability {
  52
  53 // static
  54 DomainReliabilityScheduler::Params
  55 DomainReliabilityScheduler::Params::GetFromFieldTrialsOrDefaults() {
  56   DomainReliabilityScheduler::Params params;
  57
  58   params.minimum_upload_delay =
  59       base::TimeDelta::FromSeconds(GetUnsignedFieldTrialValueOrDefault(
  60           kMinimumUploadDelayFieldTrialName, kDefaultMinimumUploadDelaySec));
  61   params.maximum_upload_delay =
  62       base::TimeDelta::FromSeconds(GetUnsignedFieldTrialValueOrDefault(
  63           kMaximumUploadDelayFieldTrialName, kDefaultMaximumUploadDelaySec));
  64   params.upload_retry_interval =
  65       base::TimeDelta::FromSeconds(GetUnsignedFieldTrialValueOrDefault(
  66           kUploadRetryIntervalFieldTrialName, kDefaultUploadRetryIntervalSec));
  67
  68   return params;
  69 }
  70
  71 DomainReliabilityScheduler::DomainReliabilityScheduler(
  72     MockableTime* time,
  73     size_t num_collectors,
  74     const Params& params,
  75     const ScheduleUploadCallback& callback)
  76     : time_(time),
  77       params_(params),
  78       callback_(callback),
  79       upload_pending_(false),
  80       upload_scheduled_(false),
  81       upload_running_(false),
  82       collector_index_(kInvalidCollectorIndex),
  83       last_upload_finished_(false) {
  84   backoff_policy_.num_errors_to_ignore = 0;
  85   backoff_policy_.initial_delay_ms =
  86       params.upload_retry_interval.InMilliseconds();
  87   backoff_policy_.multiply_factor = kMultiplyFactor;
  88   backoff_policy_.jitter_factor = kJitterFactor;
  89   backoff_policy_.maximum_backoff_ms = kMaximumBackoffMs;
  90   backoff_policy_.entry_lifetime_ms = 0;
  91   backoff_policy_.always_use_initial_delay = false;
  92
  93   for (size_t i = 0; i < num_collectors; ++i) {
  94     collectors_.push_back(
  95       new MockableTimeBackoffEntry(&backoff_policy_, time_));
  96   }
  97 }
  98
  99 DomainReliabilityScheduler::~DomainReliabilityScheduler() {}
 100
 101 void DomainReliabilityScheduler::OnBeaconAdded() {
 102   if (!upload_pending_)
 103     first_beacon_time_ = time_->NowTicks();
 104   upload_pending_ = true;
 105   MaybeScheduleUpload();
 106 }
 107
 108 size_t DomainReliabilityScheduler::OnUploadStart() {
 109   DCHECK(upload_scheduled_);
 110   DCHECK_EQ(kInvalidCollectorIndex, collector_index_);
 111   upload_pending_ = false;
 112   upload_scheduled_ = false;
 113   upload_running_ = true;
 114
 115   base::TimeTicks now = time_->NowTicks();
 116   base::TimeTicks min_upload_time;
 117   GetNextUploadTimeAndCollector(now, &min_upload_time, &collector_index_);
 118   DCHECK(min_upload_time <= now);
 119
 120   VLOG(1) << "Starting upload to collector " << collector_index_ << ".";
 121
 122   last_upload_start_time_ = now;
 123   last_upload_collector_index_ = collector_index_;
 124
 125   return collector_index_;
 126 }
 127
 128 void DomainReliabilityScheduler::OnUploadComplete(bool success) {
 129   DCHECK(upload_running_);
 130   DCHECK_NE(kInvalidCollectorIndex, collector_index_);
 131   upload_running_ = false;
 132
 133   VLOG(1) << "Upload to collector " << collector_index_
 134           << (success ? " succeeded." : " failed.");
 135
 136   net::BackoffEntry* backoff = collectors_[collector_index_];
 137   collector_index_ = kInvalidCollectorIndex;
 138   backoff->InformOfRequest(success);
 139
 140   if (!success) {
 141     // Restore upload_pending_ and first_beacon_time_ to pre-upload state,
 142     // since upload failed.
 143     upload_pending_ = true;
 144     first_beacon_time_ = old_first_beacon_time_;
 145   }
 146
 147   last_upload_end_time_ = time_->NowTicks();
 148   last_upload_success_ = success;
 149   last_upload_finished_ = true;
 150
 151   MaybeScheduleUpload();
 152 }
 153
 154 base::Value* DomainReliabilityScheduler::GetWebUIData() const {
 155   base::TimeTicks now = time_->NowTicks();
 156
 157   base::DictionaryValue* data = new base::DictionaryValue();
 158
 159   data->SetBoolean("upload_pending", upload_pending_);
 160   data->SetBoolean("upload_scheduled", upload_scheduled_);
 161   data->SetBoolean("upload_running", upload_running_);
 162
 163   data->SetInteger("scheduled_min", (scheduled_min_time_ - now).InSeconds());
 164   data->SetInteger("scheduled_max", (scheduled_max_time_ - now).InSeconds());
 165
 166   data->SetInteger("collector_index", static_cast<int>(collector_index_));
 167
 168   if (last_upload_finished_) {
 169     base::DictionaryValue* last = new base::DictionaryValue();
 170     last->SetInteger("start_time", (now - last_upload_start_time_).InSeconds());
 171     last->SetInteger("end_time", (now - last_upload_end_time_).InSeconds());
 172     last->SetInteger("collector_index",
 173         static_cast<int>(last_upload_collector_index_));
 174     last->SetBoolean("success", last_upload_success_);
 175     data->Set("last_upload", last);
 176   }
 177
 178   base::ListValue* collectors = new base::ListValue();
 179   for (size_t i = 0; i < collectors_.size(); ++i) {
 180     const net::BackoffEntry* backoff = collectors_[i];
 181     base::DictionaryValue* value = new base::DictionaryValue();
 182     value->SetInteger("failures", backoff->failure_count());
 183     value->SetInteger("next_upload",
 184         (backoff->GetReleaseTime() - now).InSeconds());
 185     collectors->Append(value);
 186   }
 187   data->Set("collectors", collectors);
 188
 189   return data;
 190 }
 191
 192 void DomainReliabilityScheduler::MakeDeterministicForTesting() {
 193   backoff_policy_.jitter_factor = 0.0;
 194 }
 195
 196 void DomainReliabilityScheduler::MaybeScheduleUpload() {
 197   if (!upload_pending_ || upload_scheduled_ || upload_running_)
 198     return;
 199
 200   upload_scheduled_ = true;
 201   old_first_beacon_time_ = first_beacon_time_;
 202
 203   base::TimeTicks now = time_->NowTicks();
 204
 205   base::TimeTicks min_by_deadline, max_by_deadline;
 206   min_by_deadline = first_beacon_time_ + params_.minimum_upload_delay;
 207   max_by_deadline = first_beacon_time_ + params_.maximum_upload_delay;
 208   DCHECK(min_by_deadline <= max_by_deadline);
 209
 210   base::TimeTicks min_by_backoff;
 211   size_t collector_index;
 212   GetNextUploadTimeAndCollector(now, &min_by_backoff, &collector_index);
 213
 214   scheduled_min_time_ = std::max(min_by_deadline, min_by_backoff);
 215   scheduled_max_time_ = std::max(max_by_deadline, min_by_backoff);
 216
 217   base::TimeDelta min_delay = scheduled_min_time_ - now;
 218   base::TimeDelta max_delay = scheduled_max_time_ - now;
 219
 220   VLOG(1) << "Scheduling upload for between " << min_delay.InSeconds()
 221           << " and " << max_delay.InSeconds() << " seconds from now.";
 222
 223   callback_.Run(min_delay, max_delay);
 224 }
 225
 226 // TODO(ttuttle): Add min and max interval to config, use that instead.
 227
 228 // TODO(ttuttle): Cap min and max intervals received from config.
 229
 230 void DomainReliabilityScheduler::GetNextUploadTimeAndCollector(
 231     base::TimeTicks now,
 232     base::TimeTicks* upload_time_out,
 233     size_t* collector_index_out) {
 234   DCHECK(upload_time_out);
 235   DCHECK(collector_index_out);
 236
 237   base::TimeTicks min_time;
 238   size_t min_index = kInvalidCollectorIndex;
 239
 240   for (size_t i = 0; i < collectors_.size(); ++i) {
 241     net::BackoffEntry* backoff = collectors_[i];
 242     // If a collector is usable, use the first one in the list.
 243     if (!backoff->ShouldRejectRequest()) {
 244       min_time = now;
 245       min_index = i;
 246       break;
 247     }
 248
 249     // If not, keep track of which will be usable soonest:
 250     base::TimeTicks time = backoff->GetReleaseTime();
 251     if (min_index == kInvalidCollectorIndex || time < min_time) {
 252       min_time = time;
 253       min_index = i;
 254     }
 255   }
 256
 257   DCHECK_NE(kInvalidCollectorIndex, min_index);
 258   *upload_time_out = min_time;
 259   *collector_index_out = min_index;
 260 }
 261
 262 }  // namespace domain_reliability