// Add version and compress.
	_, err := dst.Write([]byte{dataUsageCacheVerCurrent})
	if err != nil {
		return err
	}
	enc, err := zstd.NewWriter(dst,
		zstd.WithEncoderLevel(zstd.SpeedFastest),
		zstd.WithWindowSize(1<<20),
		zstd.WithEncoderConcurrency(2))
	if err != nil {
		return err
	}
	mEnc := msgp.NewWriter(enc)
	err = d.EncodeMsg(mEnc)
	if err != nil {