Пример #1
0
// Opens table. It returns a cache handle, which should
// be released after use.
func (t *tOps) open(f *tFile) (ch cache.Handle, err error) {
	num := f.file.Num()
	ch = t.cacheNS.Get(num, func() (charge int, value interface{}) {
		var r storage.Reader
		r, err = f.file.Open()
		if err != nil {
			return 0, nil
		}

		var bcacheNS cache.Namespace
		if bc := t.s.o.GetBlockCache(); bc != nil {
			bcacheNS = bc.GetNamespace(num)
		}
		return 1, table.NewReader(r, int64(f.size), bcacheNS, t.bpool, t.s.o)
	})
	if ch == nil && err == nil {
		err = ErrClosed
	}
	return
}
Пример #2
0
func recoverTable(s *session, o *opt.Options) error {
	// 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 mSeq uint64
	var good, corrupted int
	rec := new(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
		}
		defer reader.Close()

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

		var tSeq uint64
		var tgood, tcorrupted, blockerr int
		var imin, imax []byte
		tr := table.NewReader(reader, size, nil, bpool, o)
		iter := tr.NewIterator(nil, nil)
		iter.(iterator.ErrorCallbackSetter).SetErrorCallback(func(err error) {
			s.logf("[email protected] found error @%d %q", file.Num(), err)
			blockerr++
		})

		// Scan the table.
		for iter.Next() {
			key := iter.Key()
			_, seq, _, ok := parseIkey(key)
			if !ok {
				tcorrupted++
				continue
			}
			tgood++
			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()

		if tgood > 0 {
			if tcorrupted > 0 || blockerr > 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
				}
				reader.Close()
				if err := file.Replace(tmp); err != nil {
					return err
				}
				size = newSize
			}
			if tSeq > mSeq {
				mSeq = tSeq
			}
			// Add table to level 0.
			rec.addTable(0, file.Num(), uint64(size), imin, imax)
			s.logf("[email protected] recovered @%d N·%d C·%d B·%d S·%d Q·%d", file.Num(), tgood, tcorrupted, blockerr, size, tSeq)
		} else {
			s.logf("[email protected] unrecoverable @%d C·%d B·%d S·%d", file.Num(), tcorrupted, blockerr, size)
		}

		good += tgood
		corrupted += tcorrupted

		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 C·%d Q·%d", len(tableFiles), good, corrupted, mSeq)
	}

	// Set sequence number.
	rec.setSeq(mSeq + 1)

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

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