INFORMATION PROCESSING APPARATUS AND DATA BACKUP METHOD

• US 20090198931A1
• Filed: 01/30/2009
• Published: 08/06/2009
• Est. Priority Date: 02/01/2008
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Matsuda, Shinnosuke, Ohyama, Sadayuki, Ishii, Takanori
• Granted Patent: US 8,838,918 B2
• Time in Patent Office: Days
• US Class Current: 711/162
• 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
• CPC Class Codes: G06F 11/1441 Resetting or repowering
• CPC Class Codes: G06F 3/0614 Improving the reliability of storage systems
• CPC Class Codes: G06F 3/065 Replication mechanisms
• CPC Class Codes: G06F 3/0656 Data buffering arrangements
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD

Abstract

An information processing apparatus includes a battery for providing the interior of the information processing apparatus with power; a volatile memory for storing data; a nonvolatile memory for backupping the data stored in the volatile memory; a controller for controlling backup of the data in accordance with a process comprising the steps of: saving the data into the nonvolatile memory; upon recovery of the power from the external power source, writing back the data into the volatile memory; and deleting the data saved in the nonvolatile memory; wherein when the power from an external power source to the information processing apparatus is stopped during deleting data in the nonvolatile memory, the controller selectively writes back deleted data from the volatile memory into the nonvolatile memory.

Claims

1. An information processing apparatus operable with power from an external power source, comprising;

a volatile memory for storing data;

a nonvolatile memory for backupping the data stored in the volatile memory;

a controller for controlling backup of the data in accordance with a process comprising the steps of;

saving the data stored in the volatile memory into the nonvolatile memory when the power from the external power source to the information processing apparatus is stopped;

upon recovery of the power from the external power source, writing back the data saved in the nonvolatile memory into the volatile memory; and

deleting the data saved in the nonvolatile memory;

wherein when the power from the external power source to the information processing apparatus is stopped during deleting data in the nonvolatile memory, the controller selectively writes back deleted data from the volatile memory into the nonvolatile memory.

2. The information processing apparatus according to claim 1, further comprises a management table for managing the states of the data in the nonvolatile memory for respective blocks in the nonvolatile memory, the block being indicative of an unit of deleting data at one time;

wherein during saving the data, the controller sets a flag in the management table, the flag indicating that data is stored with respect to the corresponding block in the management table; and

wherein during deleting the data in the nonvolatile memory, the controller sets a flag indicating that data is already deleted with respect to the corresponding block in the management table.

3. The information processing apparatus according to claim 2, wherein when the power from the external power source to the information processing apparatus is stopped during deleting the data, the controller obtains, from the management table, block information for which the flag indicating that the data is already deleted is set and resaves corresponding data to the block corresponding to the block information in the nonvolatile memory.

4. The information processing apparatus according to claim 1, further comprising:

a battery for providing the interior of the information processing apparatus with power when the power from the external power source to the information processing apparatus is stopped;

wherein the controller deletes the data in accordance with a charge state of the battery.

5. The information processing apparatus according to claim 2, wherein the controller includes a memory for storing the management table.

6. A data backup method for storing data performed by an information processing apparatus operable with power from an external power source or a battery;

the data backup method comprising the steps of;

saving the data stored in a volatile memory into a nonvolatile memory when the power from the external power source to the information processing apparatus is stopped;

upon recovery of the power from the external power source, writing back the data saved in the nonvolatile memory into the volatile memory; and

deleting the data saved in the nonvolatile memory; and

writing back selectively deleted data from the volatile memory into the nonvolatile memory, when the power from the external power source to the information processing apparatus is stopped during deleting data in the nonvolatile memory.

7. The data backup method according to claim 6, further comprising the steps of:

updating states of the data for respective blocks in the nonvolatile memory, the block being indicative of an unit of deleting data at one time;

setting a flag indicating that data is stored with respect to the corresponding block in a predetermined table during saving the data in the nonvolatile memory; and

setting a flag indicating that data is already deleted with respect to the corresponding block in the predetermined table during deleting the data in the nonvolatile memory.

8. The data backup method according to claim 7, wherein when the power from the external power source to the information processing apparatus is stopped during deleting the data, block information for which the flag indicating that the data is already deleted is set is obtained from the predetermined table, and corresponding data is resaved to the block corresponding to the block information.

9. The data backup method according to claim 6, wherein the data is deleted in accordance with a charge state of the battery.

10. The data backup method according to claim 7, wherein, in the setting step, a controller sets the flag in the predetermined table stored in the controller.