src/webkit/browser/quota/quota_temporary_storage_evictor.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 "webkit/browser/quota/quota_temporary_storage_evictor.h"
   6
   7 #include <algorithm>
   8
   9 #include "base/bind.h"
  10 #include "base/metrics/histogram.h"
  11 #include "url/gurl.h"
  12 #include "webkit/browser/quota/quota_manager.h"
  13
  14 #define UMA_HISTOGRAM_MBYTES(name, sample)          \
  15   UMA_HISTOGRAM_CUSTOM_COUNTS(                      \
  16       (name), static_cast<int>((sample) / kMBytes), \
  17       1, 10 * 1024 * 1024 /* 10TB */, 100)
  18
  19 #define UMA_HISTOGRAM_MINUTES(name, sample) \
  20   UMA_HISTOGRAM_CUSTOM_TIMES(             \
  21       (name), (sample),                   \
  22       base::TimeDelta::FromMinutes(1),    \
  23       base::TimeDelta::FromDays(1), 50)
  24
  25 namespace {
  26 const int64 kMBytes = 1024 * 1024;
  27 const double kUsageRatioToStartEviction = 0.7;
  28 const int kThresholdOfErrorsToStopEviction = 5;
  29 const int kHistogramReportIntervalMinutes = 60;
  30 }
  31
  32 namespace quota {
  33
  34 const int QuotaTemporaryStorageEvictor::
  35     kMinAvailableDiskSpaceToStartEvictionNotSpecified = -1;
  36
  37 QuotaTemporaryStorageEvictor::EvictionRoundStatistics::EvictionRoundStatistics()
  38     : in_round(false),
  39       is_initialized(false),
  40       usage_overage_at_round(-1),
  41       diskspace_shortage_at_round(-1),
  42       usage_on_beginning_of_round(-1),
  43       usage_on_end_of_round(-1),
  44       num_evicted_origins_in_round(0) {
  45 }
  46
  47 QuotaTemporaryStorageEvictor::QuotaTemporaryStorageEvictor(
  48     QuotaEvictionHandler* quota_eviction_handler,
  49     int64 interval_ms)
  50     : min_available_disk_space_to_start_eviction_(
  51           kMinAvailableDiskSpaceToStartEvictionNotSpecified),
  52       quota_eviction_handler_(quota_eviction_handler),
  53       interval_ms_(interval_ms),
  54       repeated_eviction_(true),
  55       weak_factory_(this) {
  56   DCHECK(quota_eviction_handler);
  57 }
  58
  59 QuotaTemporaryStorageEvictor::~QuotaTemporaryStorageEvictor() {
  60 }
  61
  62 void QuotaTemporaryStorageEvictor::GetStatistics(
  63     std::map<std::string, int64>* statistics) {
  64   DCHECK(statistics);
  65
  66   (*statistics)["errors-on-evicting-origin"] =
  67       statistics_.num_errors_on_evicting_origin;
  68   (*statistics)["errors-on-getting-usage-and-quota"] =
  69       statistics_.num_errors_on_getting_usage_and_quota;
  70   (*statistics)["evicted-origins"] =
  71       statistics_.num_evicted_origins;
  72   (*statistics)["eviction-rounds"] =
  73       statistics_.num_eviction_rounds;
  74   (*statistics)["skipped-eviction-rounds"] =
  75       statistics_.num_skipped_eviction_rounds;
  76 }
  77
  78 void QuotaTemporaryStorageEvictor::ReportPerRoundHistogram() {
  79   DCHECK(round_statistics_.in_round);
  80   DCHECK(round_statistics_.is_initialized);
  81
  82   base::Time now = base::Time::Now();
  83   UMA_HISTOGRAM_TIMES("Quota.TimeSpentToAEvictionRound",
  84                       now - round_statistics_.start_time);
  85   if (!time_of_end_of_last_round_.is_null())
  86     UMA_HISTOGRAM_MINUTES("Quota.TimeDeltaOfEvictionRounds",
  87                           now - time_of_end_of_last_round_);
  88   UMA_HISTOGRAM_MBYTES("Quota.UsageOverageOfTemporaryGlobalStorage",
  89                        round_statistics_.usage_overage_at_round);
  90   UMA_HISTOGRAM_MBYTES("Quota.DiskspaceShortage",
  91                        round_statistics_.diskspace_shortage_at_round);
  92   UMA_HISTOGRAM_MBYTES("Quota.EvictedBytesPerRound",
  93                        round_statistics_.usage_on_beginning_of_round -
  94                        round_statistics_.usage_on_end_of_round);
  95   UMA_HISTOGRAM_COUNTS("Quota.NumberOfEvictedOriginsPerRound",
  96                        round_statistics_.num_evicted_origins_in_round);
  97 }
  98
  99 void QuotaTemporaryStorageEvictor::ReportPerHourHistogram() {
 100   Statistics stats_in_hour(statistics_);
 101   stats_in_hour.subtract_assign(previous_statistics_);
 102   previous_statistics_ = statistics_;
 103
 104   UMA_HISTOGRAM_COUNTS("Quota.ErrorsOnEvictingOriginPerHour",
 105                        stats_in_hour.num_errors_on_evicting_origin);
 106   UMA_HISTOGRAM_COUNTS("Quota.ErrorsOnGettingUsageAndQuotaPerHour",
 107                        stats_in_hour.num_errors_on_getting_usage_and_quota);
 108   UMA_HISTOGRAM_COUNTS("Quota.EvictedOriginsPerHour",
 109                        stats_in_hour.num_evicted_origins);
 110   UMA_HISTOGRAM_COUNTS("Quota.EvictionRoundsPerHour",
 111                        stats_in_hour.num_eviction_rounds);
 112   UMA_HISTOGRAM_COUNTS("Quota.SkippedEvictionRoundsPerHour",
 113                        stats_in_hour.num_skipped_eviction_rounds);
 114 }
 115
 116 void QuotaTemporaryStorageEvictor::OnEvictionRoundStarted() {
 117   if (round_statistics_.in_round)
 118     return;
 119   round_statistics_.in_round = true;
 120   round_statistics_.start_time = base::Time::Now();
 121   ++statistics_.num_eviction_rounds;
 122 }
 123
 124 void QuotaTemporaryStorageEvictor::OnEvictionRoundFinished() {
 125   // Check if skipped round
 126   if (round_statistics_.num_evicted_origins_in_round) {
 127     ReportPerRoundHistogram();
 128     time_of_end_of_last_nonskipped_round_ = base::Time::Now();
 129   } else {
 130     ++statistics_.num_skipped_eviction_rounds;
 131   }
 132   // Reset stats for next round.
 133   round_statistics_ = EvictionRoundStatistics();
 134 }
 135
 136 void QuotaTemporaryStorageEvictor::Start() {
 137   DCHECK(CalledOnValidThread());
 138   StartEvictionTimerWithDelay(0);
 139
 140   if (histogram_timer_.IsRunning())
 141     return;
 142
 143   histogram_timer_.Start(
 144       FROM_HERE, base::TimeDelta::FromMinutes(kHistogramReportIntervalMinutes),
 145       this, &QuotaTemporaryStorageEvictor::ReportPerHourHistogram);
 146 }
 147
 148 void QuotaTemporaryStorageEvictor::StartEvictionTimerWithDelay(int delay_ms) {
 149   if (eviction_timer_.IsRunning())
 150     return;
 151   eviction_timer_.Start(FROM_HERE, base::TimeDelta::FromMilliseconds(delay_ms),
 152                         this, &QuotaTemporaryStorageEvictor::ConsiderEviction);
 153 }
 154
 155 void QuotaTemporaryStorageEvictor::ConsiderEviction() {
 156   OnEvictionRoundStarted();
 157
 158   // Get usage and disk space, then continue.
 159   quota_eviction_handler_->GetUsageAndQuotaForEviction(
 160       base::Bind(&QuotaTemporaryStorageEvictor::OnGotUsageAndQuotaForEviction,
 161                  weak_factory_.GetWeakPtr()));
 162 }
 163
 164 void QuotaTemporaryStorageEvictor::OnGotUsageAndQuotaForEviction(
 165     QuotaStatusCode status,
 166     const UsageAndQuota& qau) {
 167   DCHECK(CalledOnValidThread());
 168
 169   int64 usage = qau.global_limited_usage;
 170   DCHECK_GE(usage, 0);
 171
 172   if (status != kQuotaStatusOk)
 173     ++statistics_.num_errors_on_getting_usage_and_quota;
 174
 175   int64 usage_overage = std::max(
 176       static_cast<int64>(0),
 177       usage - static_cast<int64>(qau.quota * kUsageRatioToStartEviction));
 178
 179   // min_available_disk_space_to_start_eviction_ might be < 0 if no value
 180   // is explicitly configured yet.
 181   int64 diskspace_shortage = std::max(
 182       static_cast<int64>(0),
 183       min_available_disk_space_to_start_eviction_ - qau.available_disk_space);
 184
 185   if (!round_statistics_.is_initialized) {
 186     round_statistics_.usage_overage_at_round = usage_overage;
 187     round_statistics_.diskspace_shortage_at_round = diskspace_shortage;
 188     round_statistics_.usage_on_beginning_of_round = usage;
 189     round_statistics_.is_initialized = true;
 190   }
 191   round_statistics_.usage_on_end_of_round = usage;
 192
 193   int64 amount_to_evict = std::max(usage_overage, diskspace_shortage);
 194   if (status == kQuotaStatusOk && amount_to_evict > 0) {
 195     // Space is getting tight. Get the least recently used origin and continue.
 196     // TODO(michaeln): if the reason for eviction is low physical disk space,
 197     // make 'unlimited' origins subject to eviction too.
 198     quota_eviction_handler_->GetLRUOrigin(
 199         kStorageTypeTemporary,
 200         base::Bind(&QuotaTemporaryStorageEvictor::OnGotLRUOrigin,
 201                    weak_factory_.GetWeakPtr()));
 202   } else {
 203     if (repeated_eviction_) {
 204       // No action required, sleep for a while and check again later.
 205       if (statistics_.num_errors_on_getting_usage_and_quota <
 206           kThresholdOfErrorsToStopEviction) {
 207         StartEvictionTimerWithDelay(interval_ms_);
 208       } else {
 209         // TODO(dmikurube): Try restarting eviction after a while.
 210         LOG(WARNING) << "Stopped eviction of temporary storage due to errors "
 211                         "in GetUsageAndQuotaForEviction.";
 212       }
 213     }
 214     OnEvictionRoundFinished();
 215   }
 216
 217   // TODO(dmikurube): Add error handling for the case status != kQuotaStatusOk.
 218 }
 219
 220 void QuotaTemporaryStorageEvictor::OnGotLRUOrigin(const GURL& origin) {
 221   DCHECK(CalledOnValidThread());
 222
 223   if (origin.is_empty()) {
 224     if (repeated_eviction_)
 225       StartEvictionTimerWithDelay(interval_ms_);
 226     OnEvictionRoundFinished();
 227     return;
 228   }
 229
 230   quota_eviction_handler_->EvictOriginData(origin, kStorageTypeTemporary,
 231       base::Bind(
 232           &QuotaTemporaryStorageEvictor::OnEvictionComplete,
 233           weak_factory_.GetWeakPtr()));
 234 }
 235
 236 void QuotaTemporaryStorageEvictor::OnEvictionComplete(
 237     QuotaStatusCode status) {
 238   DCHECK(CalledOnValidThread());
 239
 240   // Just calling ConsiderEviction() or StartEvictionTimerWithDelay() here is
 241   // ok.  No need to deal with the case that all of the Delete operations fail
 242   // for a certain origin.  It doesn't result in trying to evict the same
 243   // origin permanently.  The evictor skips origins which had deletion errors
 244   // a few times.
 245
 246   if (status == kQuotaStatusOk) {
 247     ++statistics_.num_evicted_origins;
 248     ++round_statistics_.num_evicted_origins_in_round;
 249     // We many need to get rid of more space so reconsider immediately.
 250     ConsiderEviction();
 251   } else {
 252     ++statistics_.num_errors_on_evicting_origin;
 253     if (repeated_eviction_) {
 254       // Sleep for a while and retry again until we see too many errors.
 255       StartEvictionTimerWithDelay(interval_ms_);
 256     }
 257     OnEvictionRoundFinished();
 258   }
 259 }
 260
 261 }  // namespace quota