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