code: func (s *Admin) TSDBCleanTombstones(_ context.Context, _ *pb.TSDBCleanTombstonesRequest) (*pb.TSDBCleanTombstonesResponse, error) {
  	db := s.db()
  	if db == nil {
  		return nil, errTSDBNotReady
  	}
  
  	if err := db.CleanTombstones(); err != nil {
  		return nil, status.Errorf(codes.Internal, "clean tombstones: %s", err)
  	}
  
  	return &pb.TSDBCleanTombstonesResponse{}, nil
  }
docs: // TSDBCleanTombstones implements pb.AdminServer.