weaviate/weaviate · error

RQ centering requires bits=4

Error message

RQ centering requires bits=4

What it means

RestoreRQCompressor validates persisted state before rebuilding an RQ compressor at startup or during restore: the stored configuration includes centering data (a non-nil mean) but a bits value other than 4. Centered RQ is only implemented for 4-bit quantization, so the on-disk configuration is internally inconsistent and cannot be restored.

Source

Thrown at adapters/repos/db/vector/compressionhelpers/compression.go:1023

	distance distancer.Provider,
	vectorCacheMaxObjects int,
	logger logrus.FieldLogger,
	dimensions int,
	bits int,
	outputDim int,
	rounds int,
	swaps [][]compression.Swap,
	signs [][]float32,
	rounding []float32,
	mean []float32,
	store *lsmkv.Store,
	allocChecker memwatch.AllocChecker,
	makeBucketOptions lsmkv.MakeBucketOptions,
	targetVector string,
	vectorForID common.VectorForID[float32],
) (VectorCompressor, error) {
	if mean != nil && bits != 4 {
		return nil, errors.New("RQ centering requires bits=4")
	}
	var rqVectorsCompressor VectorCompressor
	switch bits {
	case 1:
		quantizer, err := RestoreBinaryRotationalQuantizer(dimensions, outputDim, rounds, swaps, signs, rounding, distance)
		if err != nil {
			return nil, err
		}
		rqVectorsCompressor = &quantizedVectorsCompressor[uint64]{
			quantizer:         quantizer,
			compressedStore:   store,
			storeId:           binary.BigEndian.PutUint64,
			loadId:            binary.BigEndian.Uint64,
			targetVector:      targetVector,
			logger:            logger,
			makeBucketOptions: makeBucketOptions,
			vectorForID:       vectorForID,
		}

View on GitHub (pinned to 75aa4b6d11)

Solutions

1. Rebuild the index without centering, or with bits=4 if centering is required
2. Restore from a backup taken when the configuration was consistent

When it happens

Trigger: Thrown at adapters/repos/db/vector/compressionhelpers/compression.go:1023 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of weaviate/weaviate@75aa4b6d11 (2026-09-04). Data as JSON: /api/errors/5e08c837850b79aa. Report an issue: GitHub.