Computer system for mutual communication through network and its memory management method

• US 6,880,104 B2
• Filed: 12/20/2001
• Issued: 04/12/2005
• Est. Priority Date: 12/21/2000
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Ueno, Shinji, Abe, Shinji
• Primary Examiner(s): Baderman, Scott
• Assistant Examiner(s): Damiano, Anne L.
• Application Number:
  US10/022,271
• Publication Number:
  US 20020083368A1
• Time in Patent Office: 1,209 Days
• Field of Search: 714/14, 714/22, 714/24, 714/5, 709/203, 713/300
• US Class Current: 714/24
• CPC Class Codes: G06F 1/30 Means for acting in the event of power-supply failure or interruption, e.g. power-supply fluctuations for resetting only G06F1/24

Abstract

In the memory management method, when a failure is detected in the power supplied to a protective memory, a control toward the memory is cut off from a CPU and the power supply is switched to a standby power before the protective memory has some damaging effect; after solution of the power failure, the switching is finished, the control toward the memory is returned to the CPU, and the power supply is returned to an ordinal one; write completion of data is notified to the client at a time when the data sent from the client has been written into the protective memory; whether the last termination is abnormal or normal is checked at the activation; when the last termination is abnormal, the protective memory is returned after memories other than the protective memory are initialized at the activation; and when the last termination is normal, the protective memory is returned and thereafter all the memories are initialized at the activation.

Claims

1. A server for establishing communication upon receipt of access from a client terminal through a network, comprising:

a memory protection unit for protecting data stored in a volatile memory to be protected, in the event of a power failure, wherein said memory protection unit comprises;

power monitoring means for detecting a power failure supplied to said memory to be protected; and

switch controlling means for switching control of, and a power supply of, said memory to be protected;

wherein when a failure is detected in a power supplied to said memory to be protected, control of said memory to be protected is switched to said memory protection unit, and said power supply is switched to a standby power, before data stored in said memory to be protected is damaged; and

wherein said server notifies the client of write completion of data at a time when data sent from said client has been written into said memory to be protected.

2. The server as set forth in claim 1, wherein said switch controlling means finishes the switching, returns control of said memory to be protected to a CPU, and returns said power supply to an ordinary power supply, after resolution of the power failure.

3. The server as set forth in claim 1, wherein said memory to be protected comprises a SDRAM or a DIMM.

4. The server as set forth in claim 1, wherein said server comprises a Network Attached Storage or a File Server.

5. A server for establishing communication upon receipt of access from a client terminal through a network, comprising:

a memory protection unit for protecting data stored in a volatile memory to be protected, in the event of a power failure, wherein said memory protection unit comprises;

power monitoring means for detecting a power failure supplied to said memory to be protected; and

switch controlling means for switching control of, and a power supply of, said memory to be protected;

wherein when a failure is detected in a power supplied to said memory to be protected, control of said memory to be protected is switched to said memory protection unit, and said power supply is switched to a standby power, before data stored in said memory to be protected is damaged;

wherein the server checks whether a last termination is abnormal or normal, at a power activation;

wherein, when said last termination is abnormal, the server instructs said memory protection unit to return said memory to be protected after memories, other than said memory to be protected, are initialized at the activation; and

wherein, when said last termination is normal, the server instructs said memory protection unit to return said memory to be protected, and thereafter initializes all memories at the activation.

6. A server for establishing communication upon receipt of access from a client terminal through a network, comprising:

a memory protection unit for protecting data stored in a volatile memory to be protected, in the event of a power failure, wherein said memory protection unit comprises;

power monitoring means for detecting a power failure supplied to said memory to be protected; and

switch controlling means for switching control of, and a power supply of, said memory to be protected;

wherein when a failure is detected in a power supplied to said memory to be protected, control of said memory to be protected is switched to said memory protection unit, and said power supply is switched to a standby power, before data stored in said memory to be protected is damaged; and

wherein said switch controlling means switches said memory to be protected to a low power mode at a time of switching said power supply of said memory to the standby power.

7. A server for establishing communication upon receipt of access from a client terminal through a network, comprising:

a memory protection unit for protecting data stored in a volatile memory to be protected, in the event of a power failure, wherein said memory protection unit comprises;

power monitoring means for detecting a power failure supplied to said memory to be protected; and

switch controlling means for switching control of, and a power supply of, said memory to be protected;

wherein when a failure is detected in a power supplied to said memory to be protected, control of said memory to be protected is switched to said memory protection unit, and said power supply is switched to a standby power, before data stored in said memory to be protected is damaged; and

wherein said memory protection unit performs backup processing on data stored in said memory, in response to a user'"'"'s operation, after the switching.

8. A server for establishing communication upon receipt of access from a client terminal through a network, comprising:

a memory protection unit for protecting data stored in a volatile memory to be protected, in the event of a power failure, wherein said memory protection unit comprises;

power monitoring means for detecting a power failure supplied to said memory to be protected; and

switch controlling means for switching control of, and a power supply of, said memory to be protected;

wherein when a failure is detected in a power supplied to said memory to be protected, control of said memory to be protected is switched to said memory protection unit, and said power supply is switched to a standby power, before data stored in said memory to be protected is damaged; and

wherein said memory protection unit has a switch on an I2C bus between SPD of said memory to be protected, which comprises a DIMM, and a memory controller, to cut off a connection between the SPD and the memory controller, in the above switched state.

9. The server as set forth in claim 8, wherein said memory protection unit controls said SPD of said memory to be protected through said I2C bus.

10. A computer system for establishing mutual communication between a client terminal and a server through a network, wherein said server comprises a memory protection unit for protecting data stored in a volatile memory to be protected in the event of a power failure, said memory protection unit comprising:

power monitoring means for detecting a power failure supplied to said memory to be protected; and

switch controlling means for switching control of and a power supply of said memory to be protected;

wherein when a failure is detected in a power supplied to said memory to be protected, control of said memory to be protected is switched to said memory protection unit, and said power supply is switched to a standby power, before data stored in said memory to be protected is damaged; and

wherein said server notifies said client of write completion of data at a time when data sent from said client has been written into said memory to be protected.

11. The computer system as set forth in claim 10, wherein said switch controlling means finishes the switching, returns control of said memory to be protected to a CPU of said server, and returns said power supply to an ordinary power supply, after resolution of the power failure.

12. The computer system as set forth in claim 10, wherein said server comprises a Network Attached Storage or a File Server.

13. A computer system for establishing mutual communication between a client terminal and a server through a network, wherein said server comprises a memory protection unit for protecting data stored in a volatile memory to be protected in the event of a power failure, said memory protection unit comprising:

power monitoring means for detecting a power failure supplied to said memory to be protected; and

switch controlling means for switching control of and a power supply of said memory to be protected;

wherein when a failure is detected in a power supplied to said memory to be protected, control of said memory to be protected is switched to said memory protection unit, and said power supply is switched to a standby power, before data stored in said memory to be protected is damaged;

wherein said server checks whether a last termination is abnormal or normal, at a power activation;

wherein, when said last termination is abnormal, said server instructs said memory protection unit to return said memory to be protected after memories, other than said memory to be protected, are initialized at the activation; and

wherein, when said last termination is normal, said server instructs said memory protection unit to return said memory to be protected and thereafter initializes all memories at the activation.

14. A computer system for establishing mutual communication between a client terminal and a server through a network, wherein said server comprises a memory protection unit for protecting data stored in a volatile memory to be protected in the event of a power failure, said memory protection unit comprising:

power monitoring means for detecting a power failure supplied to said memory to be protected; and

switch controlling means for switching control of and a power supply of said memory to be protected;

wherein when a failure is detected in a power supplied to said memory to be protected, control of said memory to be protected is switched to said memory protection unit, and said power supply is switched to a standby power, before data stored in said memory to be protected is damaged; and

wherein said switch controlling means switches said memory to be protected to a low power mode at a time of switching said power supply of said memory to the standby power.

15. A memory management method of a server for establishing communication upon receipt of access from a client terminal through a network, comprising:

detecting a power failure supplied to a memory to be protected; and

switching control of and a power supply of said memory to be protected;

notifying said client of write completion of data at a time when data sent from said client has been written into said memory to be protected;

wherein when a failure is detected in a power supplied to said memory to be protected, control of said memory to be protected is cut off from a CPU, and said power supply is switched to a standby power, before said memory to be protected is damaged, so as to protect data stored in said memory to be protected, in the event of a power failure.

16. The memory management method as set forth in claim 15, further comprising finishing the switching, returning control of said memory to be protected to a CPU, and returning said power supply to an ordinary power supply, after resolution of the power failure.

17. The memory management method as set forth in claim 15, wherein said memory to be protected comprises a SDRAM or a DIMM.

18. A memory management method of a server for establishing communication upon receipt of access from a client terminal through a network, comprising:

detecting a vower failure supplied to a memory to be protected;

switching control of and a power supply of said memory to be protected;

checking whether a last termination is abnormal or normal, at a power activation;

returning said memory to be protected after initializing memories other than said memory to be protected at the activation, when said last termination is abnormal; and

returning said memory to be protected and thereafter initializing all memories at the activation when said last termination is normal;

wherein when a failure is detected in a power supplied to said memory to be protected, control of said memory to be protected is cut off from a CPU, and said power supply is switched to a standby power, before said memory to be protected is damaged, so as to protect data stored in said memory to be protected, in the event of a power failure.

19. A memory management method of a server for establishing communication upon receipt of access from a client terminal through a network, comprising:

detecting a power failure supplied to a memory to be protected;

switching control of and a power supply of said memory to be protected; and

switching said memory to be protected to a low power mode at a time of switching said power supply of said memory to the standby power;

wherein when a failure is detected in a power supplied to said memory to be protected, control of said memory to be protected is cut off from a CPU, and said power supply is switched to a standby power, before said memory to be protected is damaged, so as to protect data stored in said memory to be protected, in the event of a power failure.

20. A memory management method of a server for establishing communication upon receipt of access from a client terminal through a network, comprising:

detecting a power failure supplied to a memory to be protected;

switching control of and a power supply of said memory to be protected; and

performing backup processing on data stored in said memory, in response to a user'"'"'s operation, after the switching;

wherein when a failure is detected in a power supplied to said memory to be protected, control of said memory to be protected is cut off from a CPU, and said power supply is switched to a standby power, before said memory to be protected is damaged, so as to protect data stored in said memory to be protected, in the event of a power failure.

21. A memory management method of a server for establishing communication upon receipt of access from a client terminal through a network, comprising:

detecting a power failure supplied to a memory to be protected;

switching control of and a power supply of said memory to be protected; and

with a switch provided on an I2C bus between SPD of said memory to be protected, which comprises a DIMM, and a memory controller, cutting off a connection between the SPD and the memory controller, in the switched state;

wherein when a failure is detected in a power supplied to said memory to be protected, control of said memory to be protected is cut off from a CPU, and said power supply is switched to a standby power, before said memory to be protected is damaged, so as to protect data stored in said memory to be protected, in the event of a power failure.

22. The memory management method as set forth in claim 21, further comprising controlling said SPD of said memory to be protected through said I2C bus.

23. A memory management program of a server for establishing communication upon receipt of access from a client terminal through a network, comprising:

detecting a power failure supplied to a memory to be protected;

switching control of and a power supply of said memory to be protected; and

notifying said client of write completion of data at a time when data sent from said client has been written into said memory to be protected;

wherein when a failure is detected in a power supplied to said memory to be protected, the control of said memory to be protected is cut off from a CPU, and said power supply is switched to a standby power, before said memory to be protected is damaged, so as to protect data stored in said memory to be protected in the event of a power failure.

24. The memory management program as set forth in claim 23, further comprising finishing the switching, returning control of said memory to be protected to said CPU, and returning said power supply to an ordinary power supply, after resolution of the power failure.

25. A memory management program of a server for establishing communication upon receipt of access from a client terminal through a network, comprising:

detecting a power failure supplied to a memory to be protected;

switching control of and a power supply of said memory to be protected;

checking whether a last termination is abnormal or normal, at the power activation;

returning said memory to be protected after initializing memories other than said memory to be protected at the activation when said last termination is abnormal; and

returning said memory to be protected and thereafter initializing all memories at the activation when said last termination is normal;

wherein when a failure is detected in a power supplied to said memory to be protected, the control of said memory to be protected is cut off from a CPU, and said power supply is switched to a standby power, before said memory to be protected is damaged, so as to protect data stored in said memory to be protected in the event of a power failure.