Method loadIndexFromHintFile

engine/merge.go:269–299

Load the index from the hint file

()

// Load the index from the hint file
func (db *DB) loadIndexFromHintFile() error {
	// Check whether the hint file exists
	hintFileName := filepath.Join(db.options.DirPath, data2.HintFileSuffix)
	if _, err := os.Stat(hintFileName); os.IsNotExist(err) {
		return nil
	}

	// Open hint file
	hintFile, err := data2.OpenHintFile(db.options.DirPath, db.options.DataFileSize, db.options.FIOType)
	if err != nil {
		return err
	}

	// Read the index in the file
	var offset int64 = 0
	for {
		logRecord, size, err := hintFile.ReadLogRecord(offset)
		if err != nil {
			if err == io.EOF {
				break
			}
			return err
		}

		// Decode to get the actual index location
		pst := data2.DecodeLogRecordPst(logRecord.Value)
		db.index.Put(logRecord.Key, pst)
		offset += size
	}
	return nil
}