Database recovery apparatus and method of using dual plane nonvolatile memory
First Claim
Patent Images
1. A database recovery apparatus, comprising:
- a memory for storing a database processing program;
a power monitor and control circuit which receives a backup/recovery state signal, supplies a power source to maintain the backup state for a predetermined time if a power failure occurs during the backup state, and prevents the backup state from being performed by outputting an interrupt signal if the power failure occurs at any time other than during the backup state;
a dual plane nonvolatile memory, including a volatile memory and a nonvolatile memory divided into a plurality of block units whereby a chip is selected by a chip select signal, said dual plane nonvolatile memory performing a recovery process which copies a block unit of data of said nonvolatile memory to a block of said volatile memory in response to a backup/recovery control signal and an address read/write control signal and a backup process which overwrites the data of said volatile memory block to said nonvolatile memory block; and
database processing means for loading the program, outputting the backup/recovery control signal to said power monitor and control circuit, outputting a chip select signal to said dual plane nonvolatile memory, and outputting the address and the backup/recovery control signal so that the recovery process is performed, the data of said volatile memory block of said dual plane nonvolatile memory is updated through the address and the read/write control, and thereafter the backup process is performed by outputting the address and the backup recovery control signal.
3 Assignments
0 Petitions
Accused Products
Abstract
There are effects that the page table does not have to be administrated since the process of backing up to a disc is not necessary, that the small unit lock is possible since the backup and recovery are performed in block units, that long copy time, which was one of the greatest disadvantages in performing the transaction, is negligible, so that all the burdens imposed on the transaction can be removed and, high speed transaction processing and recovery can be performed.
45 Citations
9 Claims
-
1. A database recovery apparatus, comprising:
-
a memory for storing a database processing program; a power monitor and control circuit which receives a backup/recovery state signal, supplies a power source to maintain the backup state for a predetermined time if a power failure occurs during the backup state, and prevents the backup state from being performed by outputting an interrupt signal if the power failure occurs at any time other than during the backup state; a dual plane nonvolatile memory, including a volatile memory and a nonvolatile memory divided into a plurality of block units whereby a chip is selected by a chip select signal, said dual plane nonvolatile memory performing a recovery process which copies a block unit of data of said nonvolatile memory to a block of said volatile memory in response to a backup/recovery control signal and an address read/write control signal and a backup process which overwrites the data of said volatile memory block to said nonvolatile memory block; and database processing means for loading the program, outputting the backup/recovery control signal to said power monitor and control circuit, outputting a chip select signal to said dual plane nonvolatile memory, and outputting the address and the backup/recovery control signal so that the recovery process is performed, the data of said volatile memory block of said dual plane nonvolatile memory is updated through the address and the read/write control, and thereafter the backup process is performed by outputting the address and the backup recovery control signal. - View Dependent Claims (2, 3, 4, 5)
-
-
6. A database recovery apparatus, comprising:
-
a memory for storing a database processing program; a power monitor and control circuit which receives a backup/recovery state signal, supplies a power source to maintain the backup state for a predetermined time if a power failure occurs in the backup state, and prevents the backup state from being performed by outputting an interrupt signal if the power failure occurs at any time other than during the backup state; a first dual plane nonvolatile memory and a second dual plane nonvolatile memory, including a volatile memory and nonvolatile memory divided into a plurality of block units, whereby a chip is selected by a chip select signal, and performs a recovery process which copies a block unit of data of said nonvolatile memory to said volatile memory block in response to a backup/recovery control signal and an address read/write control signal and a backup process which overwrite the data of volatile memory block to said nonvolatile memory block; and database processing means for loading the program from said memory, outputting the backup/recovery control signal to said power monitor and control circuit, outputting a chip select signal to said first and second dual plane nonvolatile memory, and outputting the address and the backup/recovery control signal so that the recovery process is performed, the data of said volatile memory block of said first and second dual plane nonvolatile memory is updated through the address and the read/write control, and thereafter the address and the backup recovery control signal are outputted to the first dual plane nonvolatile memory, and then if the backup process fails, the database of the first dual plane nonvolatile memory is updated by reading the data of the second dual plane nonvolatile memory prior to update, and if the backup process of the first dual plane nonvolatile memory succeeds, the address and the backup/recovery control signal are outputted to the second dual plane nonvolatile memory and then if the backup process fails, the database of the second dual plane nonvolatile memory is updated by reading the updated data of the first dual plane nonvolatile memory. - View Dependent Claims (7)
-
-
8. A database recovery method applied to a database recovery apparatus using a nonvolatile memory constructed by dualization in a database system comprising the steps of:
-
a) copying a nonvolatile memory block of a first and second dual plane nonvolatile memory to a volatile memory block, updating the data of volatile memory block of said first and second dual plane nonvolatile memory, and thereafter checking whether the update performance partially succeeds; b) informing, if the update succeeded in said step a), that backup is in effect for a power monitor and control circuit, copying the updated volatile memory block of said first dual plane nonvolatile memory, and thereafter checking whether the copy succeeds; c) recovering, if the copy failed in said step b), said nonvolatile memory block of said first dual plane nonvolatile memory to a value prior to the update by using said nonvolatile memory block of said second dual plane nonvolatile memory, thereafter informing of the update failure to the power monitor and control circuit, and ending the transaction; d) informing, if the copy succeeded in said step b), the progress of the backup to said power monitor and control circuit, copying said volatile memory block of said second dual plane nonvolatile memory to said nonvolatile memory block, and checking whether the copy succeeds; e) informing, if the copy succeeded in said step d), that update is completed and ends the transaction, but if the copy failed, recovering said nonvolatile memory block of said second dual plane nonvolatile memory to the latest update value by using said nonvolatile memory block of said first dual plane nonvolatile memory, informing of the update and completion, and then ending the transaction; and f) discarding, if the update failed in said first step, the updated volatile memory block of said first and second dual plane nonvolatile memory, informing of the update failure, and ending the transaction.
-
-
9. A database recovering method utilizing a dual plane nonvolatile memory in a database system, said method comprising the steps of:
-
(a) copying a block unit of data from a nonvolatile memory to a volatile memory block unit in response to a backup/recovery control signal; (b) updating the data copied to said volatile memory block in response to a read/write control signal; (c) checking whether the updating partially succeeds; (d) informing a power monitor and control circuit of a processing of the backup if the updating partially succeeds in said step (c); (e) copying the updated data of said volatile memory to said nonvolatile memory block; (f) informing said power monitor and control circuit of the completion of the updating step after completion of said step (e), and completing the transaction; (g) discarding the updated data of said volatile memory if said updating fails in said step (c); and (h) indicating a failure of said updating step and completing the transaction.
-
Specification