High speed real-time information storage system

• US 5,867,686 A
• Filed: 11/08/1995
• Issued: 02/02/1999
• Est. Priority Date: 11/09/1993
• Status: Expired due to Term

• Current Assignee: RPX Corporation
• Original Assignee: Bruce C. Anderson, Gregory P. Spar, James G. Hunter, Kenneth H. Conner
• Inventors: Conner, Kenneth H., Hunter, James G., Spar, Gregory P., Anderson, Bruce
• Primary Examiner(s): Lintz, Paul R.
• Application Number:
  US08/555,259
• Time in Patent Office: 1,182 Days
• Field of Search: 395/608, 395/800, 395/379, 395/726, 395/472, 395/480, 395/490, 395/200.03, 395/495, 395/610
• US Class Current: 711/168
• CPC Class Codes: G06F 13/1652 in a multiprocessor architecture interprocessor communication using common memory G06F15/167
• CPC Class Codes: G06F 9/52 Program synchronisation; Mutual exclusion, e.g. by means of semaphores
• CPC Class Codes: Y10S 707/99938 Concurrency, e.g. lock management in shared database

Abstract

An information storage system includes a controller for managing the resources of a common mass storage device in order to enable multiple hosts connected to a common bus to independently read and write to the mass storage device in a relatively high speed manner on a first come, real time basis. In particular, a system of commands is provided which enables each host to read and write to the mass storage device on an independent, first come, real time basis by locking the requested address space irrespective of the origination. Even though an address storage space may be locked, the data within such space is always readable by another host. Should a subsequent host issue a command to write to the locked address space, the command is aborted and a flag is set indicating to the subsequent requesting host that the area is locked. The information storage system also provides for dynamic memory mapping which enables the mass storage device to be mapped according to a specific application.

Claims

1. A method of providing memory access to a memory mass storage device by a plurality of computers, each functioning under an independent operating system, such method comprising the steps of:

receiving a write access request identifying a memory space from a requesting computer of the plurality of computers by the memory mass storage device;

granting access and reserving the memory space for the exclusive use of the requesting computer and denying write access to the memory space by any other computer of the plurality of computers for the duration of the access grant to the requesting computer; and

receiving a write access request and a required memory size from a second requesting computer of the plurality of computers.

2. The method as in claim 1 further comprising the step of retrieving a boundary location of a most recent new data store as a starting point of an available memory space of the required memory size specified in the access request from the second requesting computer.

3. The method as in claim 2 further comprising the step of reserving a memory space of the required memory size adjacent the boundary location for the exclusive use of the second requesting computer.

4. The method as in claim 3 further comprising the step of dynamically adjusting a memory map of the memory mass storage device based upon the reserved memory space for the second computer.

5. The method as in claim 1 further comprising the step of defining the write access request as a write new chain command.

6. A method of providing memory access to a memory mass storage device by a plurality of computers, each functioning under an independent operating system, such method comprising the steps of:

receiving a write access request identifying a memory space from a first requesting computer of the plurality of computers by the memory mass storage device;

granting access and reserving the memory space for the exclusive use of the first requesting computer and denying write access to the memory space by any other computer of the plurality of computers for the duration of the access grant to the first requesting computer;

transmitting a write access request from the first requesting computer to the memory mass storage device followed by at least one data byte;

writing the at least one data byte from the first requesting computer into the identified memory space; and

storing parametric data from the first requesting computer about the at least one data byte in a reserved keys space of the identified memory space.

7. The method as in claim 6 further comprising the step of reading the parametric data about the at least one byte by a fourth computer of the plurality of computers.

8. The method as in claim 6 further comprising the step of locking the reserved keys space of the memory map by the first computer.

9. The method as in claim 8 further comprising the step of modifying the parametric data of the at least one data byte of the reserved keys space of the memory space by the first computer.

10. A computer system comprising:

a memory mass storage device;

a plurality of computers, each functioning under an independent operating system, operably connected to the memory mass storage device through an external bus;

a communication processor of the memory mass storage device operably connected to the plurality of computers through the external bus for receiving an access request from a requesting computer of the plurality of computers identifying a memory space of the memory mass storage device;

a controller of the memory mass storage device operably connected to the communication processor for granting exclusive write access to the identified memory space by the requesting computer for a duration of the access grant to the requesting computer;

means for storing at least one byte of data from the requesting computer into the identified memory space; and

a dynamic memory map containing a listing of the identified memory space.

11. The system as in claim 10 wherein the listing of the identified memory space further comprises a descriptor portion containing at least one descriptive parameter of the at least one byte of data.