International Business Machines Corporation

John A Hupcey

William F Beausoleil

Sandra Juni Schlosser

Charles R Berghorn

. A shared fixed block architecture direct access storage system and method for use with a plurality of computer systems is described. The storage system includes a shared fixed block architecture direct access storage device with a plurality of shared files. A shared fixed block architecture control unit is coupled to the shared fixed block architecture direct access storage device and to the plurality of computer systems. The shared fixed block architecture control unit also includes a data unit responsible for moving data between a shared fixed block architecture direct access storage device in the computer systems, a SETL unit responsible for processing access requests and for creating control files corresponding to each shared file, and a heart beat unit responsible for updating the control files. The method of the present invention includes the steps of receiving an access request from one of the computers for access to a selected shared file; and if a control file corresponding to this selected file has not been previously created, then creating a control file corresponding to this selected file. The control file is read to determine if it contains a record indicating that another of the computer systems already has access to a selected file and whether that access is incompatible with the current access request. Finally, if either no other system currently has access to the requested file or if another system has access to the requested file which is not incompatible, then the access request is granted.

Program storage device and computer program product for managing a

A shared fixed block architecture direct access storage system and method for use with a plurality of computer systems is described. The storage system includes a shared fixed block architecture direct access storage device with a plurality of shared files. A shared fixed block architecture control unit is coupled to the shared fixed block architecture direct access storage device and to the plurality of computer systems. The shared fixed block architecture control unit also includes a data unit responsible for moving data between a shared fixed block architecture direct access storage device in the computer systems, a SETL unit responsible for processing access requests and for creating control files corresponding to each shared file, and a heart beat unit responsible for updating the control files. The method of the present invention includes the steps of receiving an access request from one of the computers for access to a selected shared file; and if a control file corresponding to this selected file has not been previously created, then creating a control file corresponding to this selected file. The control file is read to determine if it contains a record indicating that another of the computer systems already has access to a selected file and whether that access is incompatible with the current access request. Finally, if either no other system currently has access to the requested file or if another system has access to the requested file which is not incompatible, then the access request is granted.

Growing community of inventors

Poughkeepsie, NY, United States of America

John A Hupcey