A mechanism is provided for optimizing and enhancing performance for parity based storage, particularly redundant array of independent disk storage. In such counters a problem may occur that the count value has a relative error of \xb11N, corresponding to the measurement interval. The draining spacer elements respectively and mutually comprise flow elements and sealing elements for the filtrate chamber and the non-filtrate chamber. The dielectric ceramic may also contain at least one specific rare earth element Re, such as Gd, Tb, or Dy.