safe_seed_manager.cc | Explore in Territory

// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "components/variations/service/safe_seed_manager.h"

#include <algorithm>

#include "base/base_switches.h"
#include "base/command_line.h"
#include "base/logging.h"
#include "base/metrics/histogram_functions.h"
#include "base/metrics/histogram_macros.h"
#include "components/prefs/pref_registry.h"
#include "components/prefs/pref_registry_simple.h"
#include "components/prefs/pref_service.h"
#include "components/variations/client_filterable_state.h"
#include "components/variations/pref_names.h"
#include "components/variations/variations_seed_store.h"
#include "components/variations/variations_switches.h"

namespace variations {

// Consecutive seed fetch failures are, unfortunately, a bit more common. As of
// January 2018, users at the 99.5th percentile tend to see fewer than 4
// consecutive fetch failures on mobile platforms; and users at the 99th
// percentile tend to see fewer than 5 or 6 consecutive failures on desktop
// platforms. It makes sense that the characteristics differ on mobile
// vs. desktop platforms, given that the two use different scheduling algorithms
// for the fetches. Graphs:
// [1] Android, all channels (consistently connected):
//     https://uma.googleplex.com/timeline_v2?sid=99d1d4c2490c60bcbde7afeb77c12a28
// [2] High-connectivity platforms, Stable and Beta channel (consistently
//     connected):
//     https://uma.googleplex.com/timeline_v2?sid=2db5b7278dad41cbf349f5f2cb30efd9
// [3] Other platforms, Stable and Beta channel (slightly less connected):
//     https://uma.googleplex.com/timeline_v2?sid=d4ba2f3751d211898f8e69214147c2ec
// [4] All platforms, Dev (even less connected):
//     https://uma.googleplex.com/timeline_v2?sid=5740fb22b17faa823822adfd8e00ec1a
// [5] All platforms, Canary (actually fairly well-connected!):
//     https://uma.googleplex.com/timeline_v2?sid=3e14d3e4887792bb614db9f3f2c1d48c
// Note the all of the graphs show a spike on a particular day, presumably due
// to server-side instability. Moreover, the Dev channel on desktop is an
// outlier – users on the Dev channel can experience just shy of 9 consecutive
// failures on some platforms.
// Decision: There is not an obvious threshold that both achieves a low
// false-positive rate and provides good coverage for true positives. For now,
// set a threshold that should minimize false-positives.
// TODO(isherman): Check in with the networking team about their thoughts on how
// to find a better balance here.
constexpr int kFetchFailureStreakSafeSeedThreshold = …;
constexpr int kFetchFailureStreakNullSeedThreshold = …;

SafeSeedManager::SafeSeedManager(PrefService* local_state)
    : … { … }

SafeSeedManager::~SafeSeedManager() = default;

// static
void SafeSeedManager::RegisterPrefs(PrefRegistrySimple* registry) { … }

SeedType SafeSeedManager::GetSeedType() const { … }

void SafeSeedManager::RecordFetchStarted() { … }

void SafeSeedManager::RecordSuccessfulFetch(VariationsSeedStore* seed_store) { … }

}  // namespace variations
chromium/components/variations/service/safe_seed_manager.cc
