METHOD TO WRITE DATA TO AN INFORMATION STORAGE AND RETRIEVAL SYSTEM

A method is disclosed to write data to an information storage and retrieval system comprising (n) volumes and a data cache, where that information storage and retrieval system is capable of communicating with one or more host computers. The method receives from a host computer an update for the (i)th volume, and determines the (i)th delay, where that (i)th delay is associated with the (i)th volume. The method then writes the update to said data cache interposing the (i)th delay without indicating to said host computer that the information storage and retrieval system is unavailable.