Beispiel #1
0
func (db *DB) compactionError() {
	var err error
noerr:
	// No error.
	for {
		select {
		case err = <-db.compErrSetC:
			switch {
			case err == nil:
			case err == ErrReadOnly, errors.IsCorrupted(err):
				goto hasperr
			default:
				goto haserr
			}
		case _, _ = <-db.closeC:
			return
		}
	}
haserr:
	// Transient error.
	for {
		select {
		case db.compErrC <- err:
		case err = <-db.compErrSetC:
			switch {
			case err == nil:
				goto noerr
			case err == ErrReadOnly, errors.IsCorrupted(err):
				goto hasperr
			default:
			}
		case _, _ = <-db.closeC:
			return
		}
	}
hasperr:
	// Persistent error.
	for {
		select {
		case db.compErrC <- err:
		case db.compPerErrC <- err:
		case db.writeLockC <- struct{}{}:
			// Hold write lock, so that write won't pass-through.
			db.compWriteLocking = true
		case _, _ = <-db.closeC:
			if db.compWriteLocking {
				// We should release the lock or Close will hang.
				<-db.writeLockC
			}
			return
		}
	}
}
Beispiel #2
0
func (i *indexedIterator) dataErr() bool {
	if err := i.data.Error(); err != nil {
		if i.errf != nil {
			i.errf(err)
		}
		if i.strict || !errors.IsCorrupted(err) {
			i.err = err
			return true
		}
	}
	return false
}
Beispiel #3
0
func (i *mergedIterator) iterErr(iter Iterator) bool {
	if err := iter.Error(); err != nil {
		if i.errf != nil {
			i.errf(err)
		}
		if i.strict || !errors.IsCorrupted(err) {
			i.err = err
			return true
		}
	}
	return false
}
Beispiel #4
0
func (db *DB) compactionTransact(name string, t compactionTransactInterface) {
	defer func() {
		if x := recover(); x != nil {
			if x == errCompactionTransactExiting {
				if err := t.revert(); err != nil {
					db.logf("%s revert error %q", name, err)
				}
			}
			panic(x)
		}
	}()

	const (
		backoffMin = 1 * time.Second
		backoffMax = 8 * time.Second
		backoffMul = 2 * time.Second
	)
	var (
		backoff  = backoffMin
		backoffT = time.NewTimer(backoff)
		lastCnt  = compactionTransactCounter(0)

		disableBackoff = db.s.o.GetDisableCompactionBackoff()
	)
	for n := 0; ; n++ {
		// Check wether the DB is closed.
		if db.isClosed() {
			db.logf("%s exiting", name)
			db.compactionExitTransact()
		} else if n > 0 {
			db.logf("%s retrying N·%d", name, n)
		}

		// Execute.
		cnt := compactionTransactCounter(0)
		err := t.run(&cnt)
		if err != nil {
			db.logf("%s error I·%d %q", name, cnt, err)
		}

		// Set compaction error status.
		select {
		case db.compErrSetC <- err:
		case perr := <-db.compPerErrC:
			if err != nil {
				db.logf("%s exiting (persistent error %q)", name, perr)
				db.compactionExitTransact()
			}
		case _, _ = <-db.closeC:
			db.logf("%s exiting", name)
			db.compactionExitTransact()
		}
		if err == nil {
			return
		}
		if errors.IsCorrupted(err) {
			db.logf("%s exiting (corruption detected)", name)
			db.compactionExitTransact()
		}

		if !disableBackoff {
			// Reset backoff duration if counter is advancing.
			if cnt > lastCnt {
				backoff = backoffMin
				lastCnt = cnt
			}

			// Backoff.
			backoffT.Reset(backoff)
			if backoff < backoffMax {
				backoff *= backoffMul
				if backoff > backoffMax {
					backoff = backoffMax
				}
			}
			select {
			case <-backoffT.C:
			case _, _ = <-db.closeC:
				db.logf("%s exiting", name)
				db.compactionExitTransact()
			}
		}
	}
}
Beispiel #5
0
// NewReader creates a new initialized table reader for the file.
// The fi, cache and bpool is optional and can be nil.
//
// The returned table reader instance is goroutine-safe.
func NewReader(f io.ReaderAt, size int64, fi *storage.FileInfo, cache *cache.CacheGetter, bpool *util.BufferPool, o *opt.Options) (*Reader, error) {
	if f == nil {
		return nil, errors.New("leveldb/table: nil file")
	}

	r := &Reader{
		fi:             fi,
		reader:         f,
		cache:          cache,
		bpool:          bpool,
		o:              o,
		cmp:            o.GetComparer(),
		verifyChecksum: o.GetStrict(opt.StrictBlockChecksum),
	}

	if size < footerLen {
		r.err = r.newErrCorrupted(0, size, "table", "too small")
		return r, nil
	}

	footerPos := size - footerLen
	var footer [footerLen]byte
	if _, err := r.reader.ReadAt(footer[:], footerPos); err != nil && err != io.EOF {
		return nil, err
	}
	if string(footer[footerLen-len(magic):footerLen]) != magic {
		r.err = r.newErrCorrupted(footerPos, footerLen, "table-footer", "bad magic number")
		return r, nil
	}

	var n int
	// Decode the metaindex block handle.
	r.metaBH, n = decodeBlockHandle(footer[:])
	if n == 0 {
		r.err = r.newErrCorrupted(footerPos, footerLen, "table-footer", "bad metaindex block handle")
		return r, nil
	}

	// Decode the index block handle.
	r.indexBH, n = decodeBlockHandle(footer[n:])
	if n == 0 {
		r.err = r.newErrCorrupted(footerPos, footerLen, "table-footer", "bad index block handle")
		return r, nil
	}

	// Read metaindex block.
	metaBlock, err := r.readBlock(r.metaBH, true)
	if err != nil {
		if errors.IsCorrupted(err) {
			r.err = err
			return r, nil
		} else {
			return nil, err
		}
	}

	// Set data end.
	r.dataEnd = int64(r.metaBH.offset)

	// Read metaindex.
	metaIter := r.newBlockIter(metaBlock, nil, nil, true)
	for metaIter.Next() {
		key := string(metaIter.Key())
		if !strings.HasPrefix(key, "filter.") {
			continue
		}
		fn := key[7:]
		if f0 := o.GetFilter(); f0 != nil && f0.Name() == fn {
			r.filter = f0
		} else {
			for _, f0 := range o.GetAltFilters() {
				if f0.Name() == fn {
					r.filter = f0
					break
				}
			}
		}
		if r.filter != nil {
			filterBH, n := decodeBlockHandle(metaIter.Value())
			if n == 0 {
				continue
			}
			r.filterBH = filterBH
			// Update data end.
			r.dataEnd = int64(filterBH.offset)
			break
		}
	}
	metaIter.Release()
	metaBlock.Release()

	// Cache index and filter block locally, since we don't have global cache.
	if cache == nil {
		r.indexBlock, err = r.readBlock(r.indexBH, true)
		if err != nil {
			if errors.IsCorrupted(err) {
				r.err = err
				return r, nil
			} else {
				return nil, err
			}
		}
		if r.filter != nil {
			r.filterBlock, err = r.readFilterBlock(r.filterBH)
			if err != nil {
				if !errors.IsCorrupted(err) {
					return nil, err
				}

				// Don't use filter then.
				r.filter = nil
			}
		}
	}

	return r, nil
}
Beispiel #6
0
func (r *Reader) find(key []byte, filtered bool, ro *opt.ReadOptions, noValue bool) (rkey, value []byte, err error) {
	r.mu.RLock()
	defer r.mu.RUnlock()

	if r.err != nil {
		err = r.err
		return
	}

	indexBlock, rel, err := r.getIndexBlock(true)
	if err != nil {
		return
	}
	defer rel.Release()

	index := r.newBlockIter(indexBlock, nil, nil, true)
	defer index.Release()
	if !index.Seek(key) {
		err = index.Error()
		if err == nil {
			err = ErrNotFound
		}
		return
	}
	dataBH, n := decodeBlockHandle(index.Value())
	if n == 0 {
		r.err = r.newErrCorruptedBH(r.indexBH, "bad data block handle")
		return
	}
	if filtered && r.filter != nil {
		filterBlock, frel, ferr := r.getFilterBlock(true)
		if ferr == nil {
			if !filterBlock.contains(r.filter, dataBH.offset, key) {
				frel.Release()
				return nil, nil, ErrNotFound
			}
			frel.Release()
		} else if !errors.IsCorrupted(ferr) {
			err = ferr
			return
		}
	}
	data := r.getDataIter(dataBH, nil, r.verifyChecksum, !ro.GetDontFillCache())
	defer data.Release()
	if !data.Seek(key) {
		err = data.Error()
		if err == nil {
			err = ErrNotFound
		}
		return
	}
	// Don't use block buffer, no need to copy the buffer.
	rkey = data.Key()
	if !noValue {
		if r.bpool == nil {
			value = data.Value()
		} else {
			// Use block buffer, and since the buffer will be recycled, the buffer
			// need to be copied.
			value = append([]byte{}, data.Value()...)
		}
	}
	return
}
Beispiel #7
0
// Recover a database session; need external synchronization.
func (s *session) recover() (err error) {
	defer func() {
		if os.IsNotExist(err) {
			// Don't return os.ErrNotExist if the underlying storage contains
			// other files that belong to LevelDB. So the DB won't get trashed.
			if files, _ := s.stor.GetFiles(storage.TypeAll); len(files) > 0 {
				err = &errors.ErrCorrupted{File: &storage.FileInfo{Type: storage.TypeManifest}, Err: &errors.ErrMissingFiles{}}
			}
		}
	}()

	m, err := s.stor.GetManifest()
	if err != nil {
		return
	}

	reader, err := m.Open()
	if err != nil {
		return
	}
	defer reader.Close()

	var (
		// Options.
		numLevel = s.o.GetNumLevel()
		strict   = s.o.GetStrict(opt.StrictManifest)

		jr      = journal.NewReader(reader, dropper{s, m}, strict, true)
		rec     = &sessionRecord{}
		staging = s.stVersion.newStaging()
	)
	for {
		var r io.Reader
		r, err = jr.Next()
		if err != nil {
			if err == io.EOF {
				err = nil
				break
			}
			return errors.SetFile(err, m)
		}

		err = rec.decode(r, numLevel)
		if err == nil {
			// save compact pointers
			for _, r := range rec.compPtrs {
				s.stCompPtrs[r.level] = iKey(r.ikey)
			}
			// commit record to version staging
			staging.commit(rec)
		} else {
			err = errors.SetFile(err, m)
			if strict || !errors.IsCorrupted(err) {
				return
			} else {
				s.logf("manifest error: %v (skipped)", errors.SetFile(err, m))
			}
		}
		rec.resetCompPtrs()
		rec.resetAddedTables()
		rec.resetDeletedTables()
	}

	switch {
	case !rec.has(recComparer):
		return newErrManifestCorrupted(m, "comparer", "missing")
	case rec.comparer != s.icmp.uName():
		return newErrManifestCorrupted(m, "comparer", fmt.Sprintf("mismatch: want '%s', got '%s'", s.icmp.uName(), rec.comparer))
	case !rec.has(recNextFileNum):
		return newErrManifestCorrupted(m, "next-file-num", "missing")
	case !rec.has(recJournalNum):
		return newErrManifestCorrupted(m, "journal-file-num", "missing")
	case !rec.has(recSeqNum):
		return newErrManifestCorrupted(m, "seq-num", "missing")
	}

	s.manifestFile = m
	s.setVersion(staging.finish())
	s.setNextFileNum(rec.nextFileNum)
	s.recordCommited(rec)
	return nil
}
Beispiel #8
0
func (db *DB) recoverJournalRO() error {
	// Get all journals and sort it by file number.
	allJournalFiles, err := db.s.getFiles(storage.TypeJournal)
	if err != nil {
		return err
	}
	files(allJournalFiles).sort()

	// Journals that will be recovered.
	var recJournalFiles []storage.File
	for _, jf := range allJournalFiles {
		if jf.Num() >= db.s.stJournalNum || jf.Num() == db.s.stPrevJournalNum {
			recJournalFiles = append(recJournalFiles, jf)
		}
	}

	var (
		// Options.
		strict      = db.s.o.GetStrict(opt.StrictJournal)
		checksum    = db.s.o.GetStrict(opt.StrictJournalChecksum)
		writeBuffer = db.s.o.GetWriteBuffer()

		mdb = memdb.New(db.s.icmp, writeBuffer)
	)

	// Recover journals.
	if len(recJournalFiles) > 0 {
		db.logf("[email protected] RO·Mode F·%d", len(recJournalFiles))

		var (
			jr    *journal.Reader
			buf   = &util.Buffer{}
			batch = &Batch{}
		)

		for _, jf := range recJournalFiles {
			db.logf("[email protected] recovering @%d", jf.Num())

			fr, err := jf.Open()
			if err != nil {
				return err
			}

			// Create or reset journal reader instance.
			if jr == nil {
				jr = journal.NewReader(fr, dropper{db.s, jf}, strict, checksum)
			} else {
				jr.Reset(fr, dropper{db.s, jf}, strict, checksum)
			}

			// Replay journal to memdb.
			for {
				r, err := jr.Next()
				if err != nil {
					if err == io.EOF {
						break
					}

					fr.Close()
					return errors.SetFile(err, jf)
				}

				buf.Reset()
				if _, err := buf.ReadFrom(r); err != nil {
					if err == io.ErrUnexpectedEOF {
						// This is error returned due to corruption, with strict == false.
						continue
					}

					fr.Close()
					return errors.SetFile(err, jf)
				}
				if err := batch.memDecodeAndReplay(db.seq, buf.Bytes(), mdb); err != nil {
					if !strict && errors.IsCorrupted(err) {
						db.s.logf("journal error: %v (skipped)", err)
						// We won't apply sequence number as it might be corrupted.
						continue
					}

					fr.Close()
					return errors.SetFile(err, jf)
				}

				// Save sequence number.
				db.seq = batch.seq + uint64(batch.Len())
			}

			fr.Close()
		}
	}

	// Set memDB.
	db.mem = &memDB{db: db, DB: mdb, ref: 1}

	return nil
}
Beispiel #9
0
func (db *DB) recoverJournal() error {
	// Get all journals and sort it by file number.
	allJournalFiles, err := db.s.getFiles(storage.TypeJournal)
	if err != nil {
		return err
	}
	files(allJournalFiles).sort()

	// Journals that will be recovered.
	var recJournalFiles []storage.File
	for _, jf := range allJournalFiles {
		if jf.Num() >= db.s.stJournalNum || jf.Num() == db.s.stPrevJournalNum {
			recJournalFiles = append(recJournalFiles, jf)
		}
	}

	var (
		of  storage.File // Obsolete file.
		rec = &sessionRecord{}
	)

	// Recover journals.
	if len(recJournalFiles) > 0 {
		db.logf("[email protected] F·%d", len(recJournalFiles))

		// Mark file number as used.
		db.s.markFileNum(recJournalFiles[len(recJournalFiles)-1].Num())

		var (
			// Options.
			strict      = db.s.o.GetStrict(opt.StrictJournal)
			checksum    = db.s.o.GetStrict(opt.StrictJournalChecksum)
			writeBuffer = db.s.o.GetWriteBuffer()

			jr    *journal.Reader
			mdb   = memdb.New(db.s.icmp, writeBuffer)
			buf   = &util.Buffer{}
			batch = &Batch{}
		)

		for _, jf := range recJournalFiles {
			db.logf("[email protected] recovering @%d", jf.Num())

			fr, err := jf.Open()
			if err != nil {
				return err
			}

			// Create or reset journal reader instance.
			if jr == nil {
				jr = journal.NewReader(fr, dropper{db.s, jf}, strict, checksum)
			} else {
				jr.Reset(fr, dropper{db.s, jf}, strict, checksum)
			}

			// Flush memdb and remove obsolete journal file.
			if of != nil {
				if mdb.Len() > 0 {
					if _, err := db.s.flushMemdb(rec, mdb, -1); err != nil {
						fr.Close()
						return err
					}
				}

				rec.setJournalNum(jf.Num())
				rec.setSeqNum(db.seq)
				if err := db.s.commit(rec); err != nil {
					fr.Close()
					return err
				}
				rec.resetAddedTables()

				of.Remove()
				of = nil
			}

			// Replay journal to memdb.
			mdb.Reset()
			for {
				r, err := jr.Next()
				if err != nil {
					if err == io.EOF {
						break
					}

					fr.Close()
					return errors.SetFile(err, jf)
				}

				buf.Reset()
				if _, err := buf.ReadFrom(r); err != nil {
					if err == io.ErrUnexpectedEOF {
						// This is error returned due to corruption, with strict == false.
						continue
					}

					fr.Close()
					return errors.SetFile(err, jf)
				}
				if err := batch.memDecodeAndReplay(db.seq, buf.Bytes(), mdb); err != nil {
					if !strict && errors.IsCorrupted(err) {
						db.s.logf("journal error: %v (skipped)", err)
						// We won't apply sequence number as it might be corrupted.
						continue
					}

					fr.Close()
					return errors.SetFile(err, jf)
				}

				// Save sequence number.
				db.seq = batch.seq + uint64(batch.Len())

				// Flush it if large enough.
				if mdb.Size() >= writeBuffer {
					if _, err := db.s.flushMemdb(rec, mdb, 0); err != nil {
						fr.Close()
						return err
					}

					mdb.Reset()
				}
			}

			fr.Close()
			of = jf
		}

		// Flush the last memdb.
		if mdb.Len() > 0 {
			if _, err := db.s.flushMemdb(rec, mdb, 0); err != nil {
				return err
			}
		}
	}

	// Create a new journal.
	if _, err := db.newMem(0); err != nil {
		return err
	}

	// Commit.
	rec.setJournalNum(db.journalFile.Num())
	rec.setSeqNum(db.seq)
	if err := db.s.commit(rec); err != nil {
		// Close journal on error.
		if db.journal != nil {
			db.journal.Close()
			db.journalWriter.Close()
		}
		return err
	}

	// Remove the last obsolete journal file.
	if of != nil {
		of.Remove()
	}

	return nil
}
Beispiel #10
0
func recoverTable(s *session, o *opt.Options) error {
	o = dupOptions(o)
	// Mask StrictReader, lets StrictRecovery doing its job.
	o.Strict &= ^opt.StrictReader

	// Get all tables and sort it by file number.
	tableFiles_, err := s.getFiles(storage.TypeTable)
	if err != nil {
		return err
	}
	tableFiles := files(tableFiles_)
	tableFiles.sort()

	var (
		maxSeq                                                            uint64
		recoveredKey, goodKey, corruptedKey, corruptedBlock, droppedTable int

		// We will drop corrupted table.
		strict = o.GetStrict(opt.StrictRecovery)

		rec   = &sessionRecord{}
		bpool = util.NewBufferPool(o.GetBlockSize() + 5)
	)
	buildTable := func(iter iterator.Iterator) (tmp storage.File, size int64, err error) {
		tmp = s.newTemp()
		writer, err := tmp.Create()
		if err != nil {
			return
		}
		defer func() {
			writer.Close()
			if err != nil {
				tmp.Remove()
				tmp = nil
			}
		}()

		// Copy entries.
		tw := table.NewWriter(writer, o)
		for iter.Next() {
			key := iter.Key()
			if validIkey(key) {
				err = tw.Append(key, iter.Value())
				if err != nil {
					return
				}
			}
		}
		err = iter.Error()
		if err != nil {
			return
		}
		err = tw.Close()
		if err != nil {
			return
		}
		err = writer.Sync()
		if err != nil {
			return
		}
		size = int64(tw.BytesLen())
		return
	}
	recoverTable := func(file storage.File) error {
		s.logf("[email protected] recovering @%d", file.Num())
		reader, err := file.Open()
		if err != nil {
			return err
		}
		var closed bool
		defer func() {
			if !closed {
				reader.Close()
			}
		}()

		// Get file size.
		size, err := reader.Seek(0, 2)
		if err != nil {
			return err
		}

		var (
			tSeq                                     uint64
			tgoodKey, tcorruptedKey, tcorruptedBlock int
			imin, imax                               []byte
		)
		tr, err := table.NewReader(reader, size, storage.NewFileInfo(file), nil, bpool, o)
		if err != nil {
			return err
		}
		iter := tr.NewIterator(nil, nil)
		if itererr, ok := iter.(iterator.ErrorCallbackSetter); ok {
			itererr.SetErrorCallback(func(err error) {
				if errors.IsCorrupted(err) {
					s.logf("[email protected] block corruption @%d %q", file.Num(), err)
					tcorruptedBlock++
				}
			})
		}

		// Scan the table.
		for iter.Next() {
			key := iter.Key()
			_, seq, _, kerr := parseIkey(key)
			if kerr != nil {
				tcorruptedKey++
				continue
			}
			tgoodKey++
			if seq > tSeq {
				tSeq = seq
			}
			if imin == nil {
				imin = append([]byte{}, key...)
			}
			imax = append(imax[:0], key...)
		}
		if err := iter.Error(); err != nil {
			iter.Release()
			return err
		}
		iter.Release()

		goodKey += tgoodKey
		corruptedKey += tcorruptedKey
		corruptedBlock += tcorruptedBlock

		if strict && (tcorruptedKey > 0 || tcorruptedBlock > 0) {
			droppedTable++
			s.logf("[email protected] dropped @%d Gk·%d Ck·%d Cb·%d S·%d Q·%d", file.Num(), tgoodKey, tcorruptedKey, tcorruptedBlock, size, tSeq)
			return nil
		}

		if tgoodKey > 0 {
			if tcorruptedKey > 0 || tcorruptedBlock > 0 {
				// Rebuild the table.
				s.logf("[email protected] rebuilding @%d", file.Num())
				iter := tr.NewIterator(nil, nil)
				tmp, newSize, err := buildTable(iter)
				iter.Release()
				if err != nil {
					return err
				}
				closed = true
				reader.Close()
				if err := file.Replace(tmp); err != nil {
					return err
				}
				size = newSize
			}
			if tSeq > maxSeq {
				maxSeq = tSeq
			}
			recoveredKey += tgoodKey
			// Add table to level 0.
			rec.addTable(0, file.Num(), uint64(size), imin, imax)
			s.logf("[email protected] recovered @%d Gk·%d Ck·%d Cb·%d S·%d Q·%d", file.Num(), tgoodKey, tcorruptedKey, tcorruptedBlock, size, tSeq)
		} else {
			droppedTable++
			s.logf("[email protected] unrecoverable @%d Ck·%d Cb·%d S·%d", file.Num(), tcorruptedKey, tcorruptedBlock, size)
		}

		return nil
	}

	// Recover all tables.
	if len(tableFiles) > 0 {
		s.logf("[email protected] F·%d", len(tableFiles))

		// Mark file number as used.
		s.markFileNum(tableFiles[len(tableFiles)-1].Num())

		for _, file := range tableFiles {
			if err := recoverTable(file); err != nil {
				return err
			}
		}

		s.logf("[email protected] recovered F·%d N·%d Gk·%d Ck·%d Q·%d", len(tableFiles), recoveredKey, goodKey, corruptedKey, maxSeq)
	}

	// Set sequence number.
	rec.setSeqNum(maxSeq)

	// Create new manifest.
	if err := s.create(); err != nil {
		return err
	}

	// Commit.
	return s.commit(rec)
}