Method loadDataAsQueryable

tsdb/db.go:624–705

(maxt int64)

}

func (db *DBReadOnly) loadDataAsQueryable(maxt int64) (storage.SampleAndChunkQueryable, error) {
	select {
	case <-db.closed:
		return nil, ErrClosed
	default:
	}
	blockReaders, err := db.Blocks()
	if err != nil {
		return nil, err
	}
	blocks := make([]*Block, len(blockReaders))
	for i, b := range blockReaders {
		b, ok := b.(*Block)
		if !ok {
			return nil, errors.New("unable to convert a read only block to a normal block")
		}
		blocks[i] = b
	}

	opts := DefaultHeadOptions()
	// Hard link the chunk files to a dir in db.sandboxDir in case the Head needs to truncate some of them
	// or cut new ones while replaying the WAL.
	// See https://github.com/prometheus/prometheus/issues/11618.
	err = chunks.HardLinkChunkFiles(mmappedChunksDir(db.dir), mmappedChunksDir(db.sandboxDir))
	if err != nil {
		return nil, err
	}
	opts.ChunkDirRoot = db.sandboxDir
	head, err := NewHead(nil, db.logger, nil, nil, opts, NewHeadStats())
	if err != nil {
		return nil, err
	}
	maxBlockTime := int64(math.MinInt64)
	if len(blocks) > 0 {
		maxBlockTime = blocks[len(blocks)-1].Meta().MaxTime
	}

	// Also add the WAL if the current blocks don't cover the requests time range.
	if maxBlockTime <= maxt {
		if err := head.Close(); err != nil {
			return nil, err
		}
		w, err := wlog.Open(db.logger, filepath.Join(db.dir, "wal"))
		if err != nil {
			return nil, err
		}
		var wbl *wlog.WL
		wblDir := filepath.Join(db.dir, wlog.WblDirName)
		if _, err := os.Stat(wblDir); !os.IsNotExist(err) {
			wbl, err = wlog.Open(db.logger, wblDir)
			if err != nil {
				return nil, err
			}
		}
		opts := DefaultHeadOptions()
		opts.ChunkDirRoot = db.sandboxDir
		head, err = NewHead(nil, db.logger, w, wbl, opts, NewHeadStats())
		if err != nil {