Providing mass data storage and retrieval services in an application-specific environment

The provision of mass data storage and retrieval services for the European Centre for Medium-Range Weather Forecasts (ECMWF) in Reading, UK, is discussed. Needing a major data repository system, ECMWF started in 1983 to work with the common file system (CFS) from Los Alamos. The system entered production at the end of 1984, and in October 1992 held approximately 7.5 terabytes of data. A separate project called MARS (Meteorological Archive and Retrieval System) was established to construct a meteorologist's interface to the stored data, and to deliver sections and concatenations of stored data objects in a form suitable for meteorological research. In the process of commissioning CFS (from Los Alamos) and MARS, a number of lessons have been learned about the way in which data-access, data-conversion, and data-delivery applications need to interface to the basic data service, and about the kind of structures needed on the data server to support the application layer. ECMWF is not reviewing the requirements for its next-generation data handling system. ECMWF is carrying out experiments on various commercially available systems in the final quarter of 1992, in the hope of identifying a suitable (set of) candidate(s) for a successor to CFS.<>