JPH04369020A - Information processor including large capacity storage device - Google Patents

Abstract

PURPOSE:To shorten time required for the backup of data stored in a large capacity storage device such as a magnetic disk device. CONSTITUTION:Data to be backed up to the storage device 4 and flag tables 420, 421,... corresponding to respective transfer units are prepared and a flag 440 is set up in the table corresponding to a transfer unit constituting data to be backed up which are rewritten in the device 4 during a period from the preceding backup up to the start of the succeeding backup. Since the data to be backed up are rewritten during the period from the preceding backup up to the start of the succeeding backup processing without writing all data to be backed up in a random access data backup device 5 at the time of backup processing, only the transfer unit corresponding to the table in which the flag 440 is set up is selected from the storage device 4 and written in the device 5.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information processing apparatus including a mass storage device, and more particularly to an information processing apparatus having data backup means for the mass storage device.

0002

2. Description of the Related Art In conventional information processing devices of this kind, data backup of a mass storage device is performed by a central processing unit constituting files required from among data stored in the mass storage device. This is done by writing all data from the mass storage device directly or through main memory to a random access data backup device.

[0003] For this reason, all data constituting the file that the central processing unit attempts to back up is written to the random access data backup device, even if the data has not actually been rewritten.

0004

[Problem to be Solved by the Invention] In a conventional information processing device, data backup of a large capacity storage device involves rewriting data to the random access data backup device even if the data has not been changed since the last data input. Requires action. Therefore, there is a problem that the time required for data backup becomes unreasonably long.

Therefore, an object of the present invention is to provide an information processing apparatus that can reduce data backup transfer time.

[0006]

[Means for Solving the Problems] The information processing device of the present invention provides a large capacity storage device when backing up data stored in a large capacity storage device such as a magnetic disk device using a random access data backup device. A flag table corresponding to data to be backed up and transfer unit data is prepared in the device, and the transfer unit that constitutes the data to be backed up that has been rewritten in the mass storage device from the previous backup to the next backup is prepared. By flagging the data and the corresponding table,
Instead of writing all backed up data to a random access data backup device during a backup process, the tables that are flagged because they have been rewritten between the previous backup and the next backup process and the corresponding mass storage device. The present invention is characterized in that only the above transfer unit data is selected and written to the random access data backup device.

In this specification, "transfer unit data" will be referred to as a sector.

[0008]

Embodiments Next, embodiments of the present invention will be explained with reference to the drawings.

Referring to FIG. 1, the information processing apparatus of this embodiment has a magnetic disk device 4 as a mass storage device,
A magnetic disk device 4, a central processing unit (CPU) 2, a random access data backup device 5, and a main memory (MM) 3 are connected to the I/O bus 1, respectively.

[0010] The operation of backing up data in the magnetic disk device 4 to the random access data backup device 5 in the system shown in FIG. 1 will be described below.

FIGS. 2, 3, and 4 show data storage formats in the data storage section of the magnetic disk device 4, the table section of the magnetic disk device 4, and the random access data backup device 5, respectively.

In FIG. 2, the data storage section of the magnetic disk device 4 is divided into tracks 400 to 40x from 0 to x, and each track has sectors 410 to 4 from 0 to y.
It is composed of 1y. Further, the random access data backup device 5 is composed of sectors 500 to 50z from 0 to z, as shown in FIG. Note that each of sectors 410 to 41y of the magnetic disk device 4 and sectors 500 to 41y of the random access data backup device 5
Each of the 50z has the same data length. In addition to the data section, the magnetic disk drive 4 has tables 420, 421, . . . as shown in FIG. 3 in the magnetic disk drive table section. There are at most the same number of sectors 500 to 50z in the random access data backup device 5, and each table 420, 421, . . . is composed of a magnetic disk device sector section 430, a flag section 440, and a backup device sector section 450. ing. The magnetic disk device sector section 430 contains sectors 410 to 410 that constitute files that the central processing unit 2 has decided to perform data backup.
41y is stored, and a flag section 440 stores a flag indicating whether data in that sector has been rewritten. Further, the backup device sector section 450 stores address data of sectors 500 to 50z on the random access data backup device 5, which is used when backing up data in sectors constituting a backup file on the magnetic disk device 4. There is.

The embodiments shown in FIGS. 1 to 4 are examples in which data is stored in a magnetic disk device 4. In FIG. First, the magnetic disk device 4 has a sector 41 as a file storage area.
At 0, 411, . . ., only M sectors from N sectors are secured. If the file is a file whose data should be backed up, the table 42 of the magnetic disk device table section
At 0, 421, ..., the same number of tables as the number of sectors reserved for the files to be backed up are secured between table J and table K, and the addresses of sectors N to M are stored in the magnetic disk device sector section 430. . At this time, the flag in the flag unit 440 is not set.

At the same time, the same number of sectors as the file to be backed up is secured in sectors 500, 501, . ... is written to the backup device sector section 450 of tables J to K. Note that when substitution processing is performed in the magnetic disk device 4 or the random access data backup device 5, it is necessary to write the address of the substitute destination sector in the magnetic disk device sector section 430 or the backup device sector section. Note that the above-mentioned N to M sectors, table J to K, and A to B sectors do not need to be continuous.

Next, the operation of the magnetic disk device 4 when actually writing data will be explained. Referring to FIG. 5, the magnetic disk device 4 schematically includes a control section 41, a storage section 42, and a local memory 43. The control section 41 is connected to the central processing unit 2 and MM3 via the I/O bus 1. A storage unit 42 that actually stores data transfers commands and data to the control unit 41 via an internal bus 44. When writing data to the magnetic disk device 4, the central processing unit 2 transfers to the control unit 41 the address of the sector of the storage unit 42 where the data is to be written and information as to whether data backup is to be performed. When writing data to a sector that does not require data backup, the control unit 41
It only performs the process of writing the data sent from M3 to the storage unit 42, but if it is designated as a sector that needs to be backed up, the address information of the area where the data is written is temporarily stored in the local memory 43, and then the data is written to the storage unit 42. 42
After the data transfer is completed, the control unit 41 searches the tables 420, 421, . . . corresponding to the area address stored in the local memory 43 and writes a flag in the flag section 440 of the table. Note that in order to ensure the data, when data is written to the storage unit 42, the sector is stored in the tables 420, 421, . . .
It is also possible to use a method of checking the magnetic disk device table section to see if it exists in the magnetic disk device table, and if it exists, writing a flag in the flag section 440 of the table.

Next, the operation during data backup will be explained with reference to FIGS. 1 to 5. When performing data backup processing, the central processing unit 2 first reads the magnetic disk device table sections 420, 421, . . . from the magnetic disk device 4. If a table with a flag set in the flag section 440 is found, the central processing unit 2 reads all the data of the track including the sector of the address written in the magnetic disk device sector section 430 of that table and stores it in the MM3. Next, the sector of the random access data backup device 5 (500, 5
01,...). At this time, it is searched from the table 420, 421, . . . whether or not the sector address of another sector existing in the previously read track is present in the table 420, 421, . . .
By also backing up the data of the sectors corresponding to the table with the flag set, it is possible to reduce the number of accesses to the magnetic disk device 4 and improve the data backup processing time.

As a result of the above-described operation, all the sector data of the backup file on the magnetic disk device 4 corresponding to the table (420, 421, . . . ) whose flag is set in the flag unit 440 is transferred to the random access data backup device. 5, the data backup process ends. Note that it is necessary to clear all the flags in the flag unit 440 when the data backup process is completed. If the flag is not cleared, the number of sectors that require data backup processing will increase.

[0018]

As explained above, according to the present invention, when data in a mass storage device is backed up using a random access data backup device in an information processing device, the mass storage device is rewritten. By backing up only the sectors, the effect is that the data backup transfer time can be shortened compared to the case where all the backup files are processed.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an information processing device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a file format of a data storage unit of the magnetic disk device in FIG. 1;

FIG. 3 is a diagram showing a data storage format of a table section of the magnetic disk device in FIG. 1;

FIG. 4 is a diagram showing a data storage format of the random access data backup device in FIG. 1;

FIG. 5 is a block diagram schematically showing the magnetic disk device in FIG. 1.

[Explanation of symbols]

1 I/O bus 2 Central processing unit 3 Main memory 4 Magnetic disk device 400, 401,...40x Tracks 410, 4
11,...41y Sectors 420, 421,...
Table 430 Magnetic disk device sector section 440
Flag section 450 Backup device sector section 41
Control unit 42 Storage unit 44 Internal bus 43 Local memory

Claims (3)

[Claims] Claim 1: A central processing unit, a mass storage device,
a random access data backup device for backing up data stored in the mass storage device, and a flag table corresponding to data to be backed up and each transfer unit is prepared in the mass storage device;
By setting a flag in the flag table corresponding to the transfer unit that constitutes the data to be backed up that has been rewritten in the mass storage device between the previous backup and the next backup, the next backup process is performed after the previous backup. The large-capacity data storage system is characterized in that only transfer units on the mass storage device corresponding to flag tables in which a flag has been set because rewriting has been performed before performing backup processing are selected and written to the random access data backup device. An information processing device including a capacitive storage device. 2. The information processing apparatus including a mass storage device according to claim 1, wherein the flag set in the flag table is cleared after the backup process is completed. [Claim 3] A file to be backed up as instructed by the central processing unit is divided into transfer unit data lengths, and one-to-one data backup is performed with the transfer unit data constituting the file.
A corresponding table is provided on the mass storage device, and a data backup area corresponding to the transfer unit data and the table on the mass storage device is provided on the random access data backup device, and when the data constituting the file is rewritten. A flag is set on the table corresponding to the rewritten transfer unit data, and a data backup operation is performed on only the data on the random access data backup device corresponding to the flagged table among the tables on the mass storage device. An information processing device including a large-capacity storage device characterized in that the information is rewritten when the data is processed.