Send metrics with embedded system profiles after system startup.

components/metrics/metrics_service.cc

 // Copyright 2014 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.
 
 //------------------------------------------------------------------------------
 // Description of the life cycle of a instance of MetricsService.
 //
 //  OVERVIEW
 //
 // A MetricsService instance is typically created at application startup.  It is
@@ skipping 607 matching lines @@
   log_manager_.BeginLoggingWithLog(CreateLog(MetricsLog::ONGOING_LOG));
   NotifyOnDidCreateMetricsLog();
   if (state_ == INITIALIZED) {
     // We only need to schedule that run once.
     state_ = INIT_TASK_SCHEDULED;
 
     base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
         FROM_HERE, base::Bind(&MetricsService::StartInitTask,
                               self_ptr_factory_.GetWeakPtr()),
         base::TimeDelta::FromSeconds(kInitializationDelaySeconds));
+
+    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(

[Alexei Svitkine (slow), 2017/06/08 23:59:30]

Please use the new post task APIs in base please.

i.e. base::PostDelayedTaskWithTraits

[bcwhite, 2017/06/09 15:09:27]

That API runs tasks on threads it owns rather than the main thread.  This has to
be done on the main thread.

+        FROM_HERE,
+        base::Bind(&MetricsService::RecordIndependentHistogramJob,
+                   self_ptr_factory_.GetWeakPtr()),
+        base::TimeDelta::FromSeconds(2 * kInitializationDelaySeconds));
   }
 }
 
 void MetricsService::StartInitTask() {
   client_->InitializeSystemProfileMetrics(
       base::Bind(&MetricsService::FinishedInitTask,
                  self_ptr_factory_.GetWeakPtr()));
 }
 
 void MetricsService::CloseCurrentLog() {
@@ skipping 326 matching lines @@
   DCHECK(log_manager_.current_log());
   // "true" indicates that StatisticsRecorder should include histograms in
   // persistent storage.
   histogram_snapshot_manager_.PrepareDeltas(
       base::StatisticsRecorder::begin(true), base::StatisticsRecorder::end(),
       base::Histogram::kNoFlags, base::Histogram::kUmaStabilityHistogramFlag);
   for (auto& provider : metrics_providers_)
     provider->RecordInitialHistogramSnapshots(&histogram_snapshot_manager_);
 }
 
+bool MetricsService::RecordIndependentHistogramLog() {

[Alexei Svitkine (slow), 2017/06/08 23:59:30]

Nit: Add thread_checker_ tests here and below.

[bcwhite, 2017/06/09 15:09:27]

Done.

+  std::unique_ptr<MetricsLog> log = CreateLog(MetricsLog::INDEPENDENT_LOG);

[Alexei Svitkine (slow), 2017/06/08 23:59:31]

CreateLog() uses session_id_ but this is not correct since it's not from the
current session. But I guess this is OK because we actually end up using the
system profile from the provider? If so, maybe add a comment.

[bcwhite, 2017/06/09 15:09:27]

Done.

+  for (auto& provider : metrics_providers_) {
+    if (log->LoadIndependentMetrics(provider.get())) {
+      log_manager_.PauseCurrentLog();
+      log_manager_.BeginLoggingWithLog(std::move(log));
+      log_manager_.FinishCurrentLog(log_store());
+      log_manager_.ResumePausedLog();
+      return true;
+    }
+  }
+  return false;
+}
+
+void MetricsService::RecordIndependentHistogramJob() {
+  bool found = RecordIndependentHistogramLog();
+  base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+      FROM_HERE,
+      base::Bind(&MetricsService::RecordIndependentHistogramJob,
+                 self_ptr_factory_.GetWeakPtr()),
+      base::TimeDelta::FromSeconds(found ? 5 : 900));

[Alexei Svitkine (slow), 2017/06/08 23:59:30]

Nit: instead FromMinutes(15) and move the found to outside the call.

[bcwhite, 2017/06/09 15:09:27]

Done.

+}
+
 void MetricsService::LogCleanShutdown(bool end_completed) {
   DCHECK(thread_checker_.CalledOnValidThread());
   // Redundant setting to assure that we always reset this value at shutdown
   // (and that we don't use some alternate path, and not call LogCleanShutdown).
   clean_shutdown_status_ = CLEANLY_SHUTDOWN;
   client_->OnLogCleanShutdown();
   clean_exit_beacon_.WriteBeaconValue(true);
   SetExecutionPhase(ExecutionPhase::SHUTDOWN_COMPLETE, local_state_);
   StabilityMetricsProvider(local_state_).MarkSessionEndCompleted(end_completed);
 }
 
 }  // namespace metrics