Method and apparatus for extending memory using a memory server

• US 6,516,342 B1
• Filed: 07/17/1998
• Issued: 02/04/2003
• Est. Priority Date: 07/17/1998
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Feldman, Stuart, McNiven, Geoffrey D., Marz, Ronald, Venuto, James
• Primary Examiner(s): Coulter, Kenneth R.
• Application Number:
  US09/118,608
• Time in Patent Office: 1,663 Days
• Field of Search: 709/213, 709/214, 709/215, 709/216, 711/2, 711/170, 711/147, 711/206, 711/207
• US Class Current: 709/216
• CPC Class Codes: G06F 12/08 in hierarchically structured memory systems, e.g. virtual memory systems
• CPC Class Codes: G06F 2212/154 Networked environment
• CPC Class Codes: H04L 67/01 Protocols
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A method and apparatus for extending the main memory of computer systems across network boundaries is provided. A memory server is allocated on a network server, or a separate machine connected to a network to enable client computers on the network to extend their main memory on demand for user applications. Through the utilization of the memory server, the client workstations can execute programs requiring more memory than is resident on the client without decreasing the efficiency of the network server.

Claims

1. A method for extending a local memory of a network device, comprising the steps of:

identifying an insufficiency in the amount of memory in the local memory of the network device for executing an application;

freeing up local memory space by paging out data to a memory server that is allocated to the network device, wherein the memory server resides in a dedicated memory server computer connected to the network; and

paging in data to the local memory of the network device from a remote location on the network to continue execution of the application.

2. The method of claim 1, further comprising the steps of:

mirroring the data that is paged out to the allocated memory server to a mirror memory server; and

informing the mirror memory server that the data paged in to the local memory from the allocated memory server is no longer resident in the allocated memory server.

3. The method of claim 1, further comprising the steps of:

providing a virtual memory manager in the network device; and

providing a memory server manager on at least one other network device.

4. A method for extending the local memory of a network connected computer (client) across network boundaries comprising the steps of:

allocating a memory area in communication with the computer network, wherein said step of allocating is performed within a dedicated memory server computer connected to the network and a network server;

transferring data from the local memory of the network connected computer to the allocated memory area;

transferring data from the allocated memory to the local memory of the computer system as needed;

recording a location of the data transferred to the allocated memory in the network connected computer; and

continuing execution of an application.

5. The method as claimed in claim 4, further comprising the step of:

identifying an insufficient amount of the local memory in the network connected computer for executing the application, said steps of transferring data being performed after said step of identifying.

6. The method as claimed in claim 4, wherein said step of allocating is performed within a memory resident on a network server.

7. The method as claimed in claim 4, further comprising the steps of:

providing a mirror memory server in communication with said allocated memory area;

mirroring the data transferred from the local memory to the allocated memory area to the mirror memory server; and

informing the mirror memory server that the data transferred to the local memory from the allocated memory area is no longer resident in the allocated memory area.

8. The method as claimed in claim 4, further comprising the step of providing a communication protocol between the network connected computer, and the allocated memory area.

9. The method as claimed in claim 7, further comprising the step of providing a communication protocol between the network connected computer, the allocated memory area and the mirror memory server.

10. A method for extending the local memory of a network connected computer (client) across network boundaries comprising the steps of:

allocating a memory area in communication with the computer network;

transferring data from the local memory of the network connected computer to the allocated memory area;

transferring data from the allocated memory to the local memory of the computer system as needed;

recording a location of the data transferred to the allocated memory in the network connected computer; and

continuing execution of an application, and further comprising the steps of;

providing a virtual memory manager in each network connected computer; and

providing a memory server manager on at least one network connected computer.

11. An apparatus for extending a local memory of a computer connected to a computer system comprising:

a memory server for providing additional memory to the computer system when an insufficiency in local memory is determined; and

communication means coupled to said memory server and the computer system for enabling the extension of the local memory of the computer to the memory server by the computer system, wherein said communication means further comprises;

a computer network connecting a plurality of computers to a network server and the memory server, said computer system being one of said plurality of computers connected to the computer network;

control means disposed in each of said plurality of computers and the network server for controlling communication between each of said plurality of computers, the network server, and the memory server; and

a communication protocol for enabling efficient communication between said control means and said memory server.

12. The apparatus according to claim 11, wherein said memory server comprises a designated memory area resident on the network server.

13. The apparatus according to claim 11, wherein said memory server comprises a designated computer connected to the computer network.

14. The apparatus according to claim 11, wherein said control means comprises:

a virtual memory manager in each of said plurality of computers; and

a memory server manager disposed within the network server.

15. The apparatus of claim 11, wherein data defining the local memory is transferred to the memory server, and the data from the memory server is transferred to the computer system as needed.