storage/VacuumManager.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  * vim: sw=2 ts=2 et lcs=trail\:.,tab\:>~ :
   3  * This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "mozilla/DebugOnly.h"
   8
   9 #include "VacuumManager.h"
  10
  11 #include "mozilla/Services.h"
  12 #include "mozilla/Preferences.h"
  13 #include "nsIObserverService.h"
  14 #include "nsIFile.h"
  15 #include "nsThreadUtils.h"
  16 #include "mozilla/Logging.h"
  17 #include "prtime.h"
  18
  19 #include "mozStorageConnection.h"
  20 #include "mozIStorageStatement.h"
  21 #include "mozIStorageAsyncStatement.h"
  22 #include "mozIStoragePendingStatement.h"
  23 #include "mozIStorageError.h"
  24 #include "mozStorageHelper.h"
  25 #include "nsXULAppAPI.h"
  26
  27 #define OBSERVER_TOPIC_IDLE_DAILY "idle-daily"
  28 #define OBSERVER_TOPIC_XPCOM_SHUTDOWN "xpcom-shutdown"
  29
  30 // Used to notify begin and end of a heavy IO task.
  31 #define OBSERVER_TOPIC_HEAVY_IO "heavy-io-task"
  32 #define OBSERVER_DATA_VACUUM_BEGIN u"vacuum-begin"
  33 #define OBSERVER_DATA_VACUUM_END u"vacuum-end"
  34
  35 // This preferences root will contain last vacuum timestamps (in seconds) for
  36 // each database.  The database filename is used as a key.
  37 #define PREF_VACUUM_BRANCH "storage.vacuum.last."
  38
  39 // Time between subsequent vacuum calls for a certain database.
  40 #define VACUUM_INTERVAL_SECONDS 30 * 86400 // 30 days.
  41
  42 extern mozilla::LazyLogModule gStorageLog;
  43
  44 namespace mozilla {
  45 namespace storage {
  46
  47 namespace {
  48
  49 ////////////////////////////////////////////////////////////////////////////////
  50 //// BaseCallback
  51
  52 class BaseCallback : public mozIStorageStatementCallback
  53 {
  54 public:
  55   NS_DECL_ISUPPORTS
  56   NS_DECL_MOZISTORAGESTATEMENTCALLBACK
  57   BaseCallback() {}
  58 protected:
  59   virtual ~BaseCallback() {}
  60 };
  61
  62 NS_IMETHODIMP
  63 BaseCallback::HandleError(mozIStorageError *aError)
  64 {
  65 #ifdef DEBUG
  66   int32_t result;
  67   nsresult rv = aError->GetResult(&result);
  68   NS_ENSURE_SUCCESS(rv, rv);
  69   nsAutoCString message;
  70   rv = aError->GetMessage(message);
  71   NS_ENSURE_SUCCESS(rv, rv);
  72
  73   nsAutoCString warnMsg;
  74   warnMsg.AppendLiteral("An error occured during async execution: ");
  75   warnMsg.AppendInt(result);
  76   warnMsg.Append(' ');
  77   warnMsg.Append(message);
  78   NS_WARNING(warnMsg.get());
  79 #endif
  80   return NS_OK;
  81 }
  82
  83 NS_IMETHODIMP
  84 BaseCallback::HandleResult(mozIStorageResultSet *aResultSet)
  85 {
  86   // We could get results from PRAGMA statements, but we don't mind them.
  87   return NS_OK;
  88 }
  89
  90 NS_IMETHODIMP
  91 BaseCallback::HandleCompletion(uint16_t aReason)
  92 {
  93   // By default BaseCallback will just be silent on completion.
  94   return NS_OK;
  95 }
  96
  97 NS_IMPL_ISUPPORTS(
  98   BaseCallback
  99 , mozIStorageStatementCallback
 100 )
 101
 102 ////////////////////////////////////////////////////////////////////////////////
 103 //// Vacuumer declaration.
 104
 105 class Vacuumer : public BaseCallback
 106 {
 107 public:
 108   NS_DECL_MOZISTORAGESTATEMENTCALLBACK
 109
 110   explicit Vacuumer(mozIStorageVacuumParticipant *aParticipant);
 111
 112   bool execute();
 113   nsresult notifyCompletion(bool aSucceeded);
 114
 115 private:
 116   nsCOMPtr<mozIStorageVacuumParticipant> mParticipant;
 117   nsCString mDBFilename;
 118   nsCOMPtr<mozIStorageConnection> mDBConn;
 119 };
 120
 121 ////////////////////////////////////////////////////////////////////////////////
 122 //// Vacuumer implementation.
 123
 124 Vacuumer::Vacuumer(mozIStorageVacuumParticipant *aParticipant)
 125   : mParticipant(aParticipant)
 126 {
 127 }
 128
 129 bool
 130 Vacuumer::execute()
 131 {
 132   MOZ_ASSERT(NS_IsMainThread(), "Must be running on the main thread!");
 133
 134   // Get the connection and check its validity.
 135   nsresult rv = mParticipant->GetDatabaseConnection(getter_AddRefs(mDBConn));
 136   NS_ENSURE_SUCCESS(rv, false);
 137   bool ready = false;
 138   if (!mDBConn || NS_FAILED(mDBConn->GetConnectionReady(&ready)) || !ready) {
 139     NS_WARNING("Unable to get a connection to vacuum database");
 140     return false;
 141   }
 142
 143   // Ask for the expected page size.  Vacuum can change the page size, unless
 144   // the database is using WAL journaling.
 145   // TODO Bug 634374: figure out a strategy to fix page size with WAL.
 146   int32_t expectedPageSize = 0;
 147   rv = mParticipant->GetExpectedDatabasePageSize(&expectedPageSize);
 148   if (NS_FAILED(rv) || !Service::pageSizeIsValid(expectedPageSize)) {
 149     NS_WARNING("Invalid page size requested for database, will use default ");
 150     NS_WARNING(mDBFilename.get());
 151     expectedPageSize = Service::getDefaultPageSize();
 152   }
 153
 154   // Get the database filename.  Last vacuum time is stored under this name
 155   // in PREF_VACUUM_BRANCH.
 156   nsCOMPtr<nsIFile> databaseFile;
 157   mDBConn->GetDatabaseFile(getter_AddRefs(databaseFile));
 158   if (!databaseFile) {
 159     NS_WARNING("Trying to vacuum a in-memory database!");
 160     return false;
 161   }
 162   nsAutoString databaseFilename;
 163   rv = databaseFile->GetLeafName(databaseFilename);
 164   NS_ENSURE_SUCCESS(rv, false);
 165   mDBFilename = NS_ConvertUTF16toUTF8(databaseFilename);
 166   MOZ_ASSERT(!mDBFilename.IsEmpty(), "Database filename cannot be empty");
 167
 168   // Check interval from last vacuum.
 169   int32_t now = static_cast<int32_t>(PR_Now() / PR_USEC_PER_SEC);
 170   int32_t lastVacuum;
 171   nsAutoCString prefName(PREF_VACUUM_BRANCH);
 172   prefName += mDBFilename;
 173   rv = Preferences::GetInt(prefName.get(), &lastVacuum);
 174   if (NS_SUCCEEDED(rv) && (now - lastVacuum) < VACUUM_INTERVAL_SECONDS) {
 175     // This database was vacuumed recently, skip it.
 176     return false;
 177   }
 178
 179   // Notify that we are about to start vacuuming.  The participant can opt-out
 180   // if it cannot handle a vacuum at this time, and then we'll move to the next
 181   // one.
 182   bool vacuumGranted = false;
 183   rv = mParticipant->OnBeginVacuum(&vacuumGranted);
 184   NS_ENSURE_SUCCESS(rv, false);
 185   if (!vacuumGranted) {
 186     return false;
 187   }
 188
 189   // Notify a heavy IO task is about to start.
 190   nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
 191   if (os) {
 192     rv =
 193       os->NotifyObservers(nullptr, OBSERVER_TOPIC_HEAVY_IO,
 194                           OBSERVER_DATA_VACUUM_BEGIN);
 195     MOZ_ASSERT(NS_SUCCEEDED(rv), "Should be able to notify");
 196   }
 197
 198   // Execute the statements separately, since the pragma may conflict with the
 199   // vacuum, if they are executed in the same transaction.
 200   nsCOMPtr<mozIStorageAsyncStatement> pageSizeStmt;
 201   nsAutoCString pageSizeQuery(MOZ_STORAGE_UNIQUIFY_QUERY_STR
 202                               "PRAGMA page_size = ");
 203   pageSizeQuery.AppendInt(expectedPageSize);
 204   rv = mDBConn->CreateAsyncStatement(pageSizeQuery,
 205                                      getter_AddRefs(pageSizeStmt));
 206   NS_ENSURE_SUCCESS(rv, false);
 207   RefPtr<BaseCallback> callback = new BaseCallback();
 208   nsCOMPtr<mozIStoragePendingStatement> ps;
 209   rv = pageSizeStmt->ExecuteAsync(callback, getter_AddRefs(ps));
 210   NS_ENSURE_SUCCESS(rv, false);
 211
 212   nsCOMPtr<mozIStorageAsyncStatement> stmt;
 213   rv = mDBConn->CreateAsyncStatement(NS_LITERAL_CSTRING(
 214     "VACUUM"
 215   ), getter_AddRefs(stmt));
 216   NS_ENSURE_SUCCESS(rv, false);
 217   rv = stmt->ExecuteAsync(this, getter_AddRefs(ps));
 218   NS_ENSURE_SUCCESS(rv, false);
 219
 220   return true;
 221 }
 222
 223 ////////////////////////////////////////////////////////////////////////////////
 224 //// mozIStorageStatementCallback
 225
 226 NS_IMETHODIMP
 227 Vacuumer::HandleError(mozIStorageError *aError)
 228 {
 229   int32_t result;
 230   nsresult rv;
 231   nsAutoCString message;
 232
 233 #ifdef DEBUG
 234   rv = aError->GetResult(&result);
 235   NS_ENSURE_SUCCESS(rv, rv);
 236   rv = aError->GetMessage(message);
 237   NS_ENSURE_SUCCESS(rv, rv);
 238
 239   nsAutoCString warnMsg;
 240   warnMsg.AppendLiteral("Unable to vacuum database: ");
 241   warnMsg.Append(mDBFilename);
 242   warnMsg.AppendLiteral(" - ");
 243   warnMsg.AppendInt(result);
 244   warnMsg.Append(' ');
 245   warnMsg.Append(message);
 246   NS_WARNING(warnMsg.get());
 247 #endif
 248
 249   if (MOZ_LOG_TEST(gStorageLog, LogLevel::Error)) {
 250     rv = aError->GetResult(&result);
 251     NS_ENSURE_SUCCESS(rv, rv);
 252     rv = aError->GetMessage(message);
 253     NS_ENSURE_SUCCESS(rv, rv);
 254     MOZ_LOG(gStorageLog, LogLevel::Error,
 255            ("Vacuum failed with error: %d '%s'. Database was: '%s'",
 256             result, message.get(), mDBFilename.get()));
 257   }
 258   return NS_OK;
 259 }
 260
 261 NS_IMETHODIMP
 262 Vacuumer::HandleResult(mozIStorageResultSet *aResultSet)
 263 {
 264   NS_NOTREACHED("Got a resultset from a vacuum?");
 265   return NS_OK;
 266 }
 267
 268 NS_IMETHODIMP
 269 Vacuumer::HandleCompletion(uint16_t aReason)
 270 {
 271   if (aReason == REASON_FINISHED) {
 272     // Update last vacuum time.
 273     int32_t now = static_cast<int32_t>(PR_Now() / PR_USEC_PER_SEC);
 274     MOZ_ASSERT(!mDBFilename.IsEmpty(), "Database filename cannot be empty");
 275     nsAutoCString prefName(PREF_VACUUM_BRANCH);
 276     prefName += mDBFilename;
 277     DebugOnly<nsresult> rv = Preferences::SetInt(prefName.get(), now);
 278     MOZ_ASSERT(NS_SUCCEEDED(rv), "Should be able to set a preference");
 279   }
 280
 281   notifyCompletion(aReason == REASON_FINISHED);
 282
 283   return NS_OK;
 284 }
 285
 286 nsresult
 287 Vacuumer::notifyCompletion(bool aSucceeded)
 288 {
 289   nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
 290   if (os) {
 291     os->NotifyObservers(nullptr, OBSERVER_TOPIC_HEAVY_IO,
 292                         OBSERVER_DATA_VACUUM_END);
 293   }
 294
 295   nsresult rv = mParticipant->OnEndVacuum(aSucceeded);
 296   NS_ENSURE_SUCCESS(rv, rv);
 297
 298   return NS_OK;
 299 }
 300
 301 } // namespace
 302
 303 ////////////////////////////////////////////////////////////////////////////////
 304 //// VacuumManager
 305
 306 NS_IMPL_ISUPPORTS(
 307   VacuumManager
 308 , nsIObserver
 309 )
 310
 311 VacuumManager *
 312 VacuumManager::gVacuumManager = nullptr;
 313
 314 already_AddRefed<VacuumManager>
 315 VacuumManager::getSingleton()
 316 {
 317   //Don't allocate it in the child Process.
 318   if (!XRE_IsParentProcess()) {
 319     return nullptr;
 320   }
 321
 322   if (!gVacuumManager) {
 323     auto manager = MakeRefPtr<VacuumManager>();
 324     MOZ_ASSERT(gVacuumManager == manager.get());
 325     return manager.forget();
 326   }
 327   return do_AddRef(gVacuumManager);
 328 }
 329
 330 VacuumManager::VacuumManager()
 331   : mParticipants("vacuum-participant")
 332 {
 333   MOZ_ASSERT(!gVacuumManager,
 334              "Attempting to create two instances of the service!");
 335   gVacuumManager = this;
 336 }
 337
 338 VacuumManager::~VacuumManager()
 339 {
 340   // Remove the static reference to the service.  Check to make sure its us
 341   // in case somebody creates an extra instance of the service.
 342   MOZ_ASSERT(gVacuumManager == this,
 343              "Deleting a non-singleton instance of the service");
 344   if (gVacuumManager == this) {
 345     gVacuumManager = nullptr;
 346   }
 347 }
 348
 349 ////////////////////////////////////////////////////////////////////////////////
 350 //// nsIObserver
 351
 352 NS_IMETHODIMP
 353 VacuumManager::Observe(nsISupports *aSubject,
 354                        const char *aTopic,
 355                        const char16_t *aData)
 356 {
 357   if (strcmp(aTopic, OBSERVER_TOPIC_IDLE_DAILY) == 0) {
 358     // Try to run vacuum on all registered entries.  Will stop at the first
 359     // successful one.
 360     nsCOMArray<mozIStorageVacuumParticipant> entries;
 361     mParticipants.GetEntries(entries);
 362     // If there are more entries than what a month can contain, we could end up
 363     // skipping some, since we run daily.  So we use a starting index.
 364     static const char* kPrefName = PREF_VACUUM_BRANCH "index";
 365     int32_t startIndex = Preferences::GetInt(kPrefName, 0);
 366     if (startIndex >= entries.Count()) {
 367       startIndex = 0;
 368     }
 369     int32_t index;
 370     for (index = startIndex; index < entries.Count(); ++index) {
 371       RefPtr<Vacuumer> vacuum = new Vacuumer(entries[index]);
 372       // Only vacuum one database per day.
 373       if (vacuum->execute()) {
 374         break;
 375       }
 376     }
 377     DebugOnly<nsresult> rv = Preferences::SetInt(kPrefName, index);
 378     MOZ_ASSERT(NS_SUCCEEDED(rv), "Should be able to set a preference");
 379   }
 380
 381   return NS_OK;
 382 }
 383
 384 } // namespace storage
 385 } // namespace mozilla