High speed file access control method and computer system including a plurality of storage subsystems connected on a bus

In a method of operating a storage array system comprising a plurality of storage subsystems connected on a bus to a computer system, a method of conducting one of a read cycle and a write cycle, the method comprising the steps of:

• receiving one of a write and a read request as a request to a single logical storage with respect to a data file;
• dividing the request to a single logical storage into a plurality of instructions for a plurality of virtual storages corresponding to the storage subsystems with respect to a plurality of data subfiles;
• issuing the plurality of instructions respectively to a plurality of the storage subsystems, serially over the bus;
• accessing a data corresponding to one of the instructions in each of the corresponding storage subsystems;
• transferring the data corresponding to the instruction from the corresponding storage subsystem to the bus;
• and
• combining the data to provide the data file in response to the request.

In a method of operating a storage array system comprising storage subsystems connected on a bus to a computer system through individual disconnect reconnect units, a method of conducting a write cycle, the method comprising the steps of:

• issuing a plurality of write instructions respectively for a plurality of the storage subsystems, serially over the bus;
• operating the disconnect reconnect units to serially connect the storage subsystems for receiving respective write instructions;
• in response to receipt of the write instructions in the storage subsystems, respectively, operating the disconnect reconnect units for disconnecting the respective storage subsystems;
• after disconnecting each storage subsystem, writing data corresponding to ones of the write instruction in the corresponding storage subsystem, and thereafter sending a write end message to the bus;
• and
• controlling all of said steps so that said writing step for each storage subsystem is conducted in parallel with other operations of the storage subsystems.