JPH06250793A - Data processor - Google Patents

Abstract

PURPOSE:To improve the speed of access to an auxiliary storage device by storing a seek movement quantity at individual data to be access object and reallocating the write positions of data on a recording surface so that the total seek movement quantity becomes smaller while an application program is executed for a prescribed time. CONSTITUTION:Each time the auxiliary storage device 3 is accessed, the quantity of seek movement of a read head on the recording surface 7 is stored, at individual data. The difference in sector number between the last accessed data and current accessed data corresponds to the seek movement quantity and when the data 15 are widely dispersed and recorded on the recording surface 7, the total seek movement quantity of the respective data 15 becomes large. A data reallocation control part 13 reallocates the dispersed data 15 on the recording surface 7 so that they are mutually approaching. Consequently, when the same application program is executed, the seek movement quantity of the head becomes small on the average and the access speed is increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data processing device for increasing the access speed when data is read from or written to an auxiliary storage device such as a magnetic disk device.

[0002]

2. Description of the Related Art In a computer or other data processing device, a large amount of data is stored in an auxiliary storage device such as a magnetic disk device, which is accessed as necessary to execute arithmetic processing. FIG. 2 shows a block diagram of a conventional data processing device. This device is a device configured to control the application program 1 by the operating system 2 and process the data read from the auxiliary storage device 3. The auxiliary storage device 3 is composed of a large-capacity storage device such as a magnetic disk device or an optical disk device. The cache memory 4 is a memory for temporarily storing the data read from the auxiliary storage device 3 and enabling high speed access. The operating system 2 includes a file system 5 and a disk control unit 6.

When the application program 1 requests the operating system 2 to access the auxiliary storage device 3, the above-mentioned device determines to which part of the auxiliary storage device 3 the file system 5 accesses to the disk control unit 6. Specify and request access. Although the disk control unit 6 accesses the auxiliary storage device 3, the contents that have been read once are stored in the cache memory 4. When the application program 1 requests access to the auxiliary storage device 3 again, if the data to be accessed corresponds to the data stored in the cache memory 4, the disk control unit 6 reads it and outputs it to the file system. The result is returned to 5.

FIG. 3 shows an explanatory view of a conventional data transfer operation. For example, a large number of tracks 8 are formed on the recording surface 7 of the magnetic disk device. Data is written here. When there is a data access request, the head 9 performs a seek operation in the direction of arrow X in the figure to execute the data access of the designated track 8. When accessing the data written in different tracks 8, the head 9 slides in the direction of arrow X each time, and the data is read and written. Generally, the access speed accompanied by the mechanical operation by the head 9 is much slower than that of a semiconductor memory or the like. Therefore, a certain amount of data is transferred to the cache memory 4 composed of a semiconductor memory, and thereafter the operating system 2 shown in FIG.
The data stored in is accessed to speed up data processing.

[0005]

However, the conventional general data processing apparatus as described above has the following problems. First, in the cache memory 4 provided for speeding up data processing, a RAM (random access memory) used as a main storage device of the data processing device is provided.
Is used. An application program is also stored in the main storage device at the same time.

In order to increase the cache hit rate, it is better to increase the size of the cache memory, but this may reduce the memory size for storing the application program and may limit the operation of the application program. there were. Conversely, if the memory size of the cache memory is set too small, it is possible to store a large size application program.However, when data is accessed, cache miss hits increase and the number of disk accesses increases, so There was also a problem that the speed could not be sufficiently improved.

The present invention has been made in view of the above points, and provides a data processing device for improving the access speed of the auxiliary storage device when the storage capacity of the main storage device is limited as described above. It is intended to be provided.

[0008]

A data processing apparatus of the present invention includes an access monitoring unit for monitoring an access operation of an auxiliary storage device during execution of an application program, and an access monitoring unit for each data to be accessed. A statistical data storage unit that stores the seek movement amount that the head seeks on the recording surface of the auxiliary storage device, and the statistical data storage unit is read, and the total seek movement amount during the execution of the application program for a predetermined time is A data rearrangement control unit for rearranging the writing position of the data on the recording surface so as to be smaller.

[0009]

With this device, each time the auxiliary storage device is accessed, the seek movement amount that the head seeks on the recording surface is stored for each data. The difference between the sector numbers of the data accessed last time and the data accessed this time corresponds to the seek movement amount. If data is widely distributed and recorded on the recording surface,
The total seek movement amount of each data becomes large. The data rearrangement control unit rearranges the data thus dispersed on the recording surface so as to approach each other. As a result, when the same application program is executed thereafter, the seek movement amount of the head that seeks each time data is accessed becomes smaller on average, and the access speed can be improved.

[0010]

The present invention will be described in detail below with reference to the embodiments shown in the drawings. FIG. 1 is an explanatory diagram showing an embodiment of a data processing device of the present invention. It should be noted that (a) of this figure is a block diagram of the data processing device, and (b) is a diagram for explaining the rearrangement operation. In the figure, this device includes an operating system 10 for controlling execution of an application program 1,
It is composed of the auxiliary storage device 3. The apparatus of the present invention does not have a cache memory in this embodiment.
This is because the present invention aims to improve the access speed when the auxiliary storage device 3 is directly accessed by effectively rearranging the write position of the data written in the auxiliary storage device 3. However, for example, when a cache memory having a relatively small memory size is used, the auxiliary storage device 3 is frequently accessed in the case of a cache miss. It is also effective to employ the present invention in order to improve the access speed in this case.

The operating system 10 comprises a file system 5 and a disk control unit 6. These configurations are similar to those of the conventional data processing device. Also,
In addition to the above, the device of the present invention is provided with an access monitoring unit 11, a statistical data storage unit 12, and a data rearrangement control unit 13. The access monitoring unit 11 monitors the access operation of the disk control unit 6 with respect to the auxiliary storage device 3, and determines what kind of access to which recording surface of the auxiliary storage device 3 requested by the file system 5, that is, read processing or write processing. Information, the size of data to be accessed, etc. The statistical data storage unit 12 is a unit for storing statistical data generated based on the information received by the access monitoring unit 11 by the monitoring operation.

FIG. 4 shows the contents of the statistical data.
For example, this statistical data includes a sector number 16, a data size 17, and a seek movement amount 18. The sector number 16 is, for example, a number indicating a data writing position on the magnetic disk and indicates at which position on which track the data is written. The data size 17 is a part indicating how many consecutive sectors the sector number 16 has been written with the data to be accessed. The seek movement amount 18 is a portion for storing data corresponding to the distance of the seek operation of the head when accessing the data of the sector number 16. Specifically, for example, the seek movement amount 18 is calculated based on the difference between the sector number 16 of the previously accessed data and the sector number 16 of the currently accessed data.

Returning to FIG. 1 again, the data relocation control unit 13 reads the statistical data having the above-described configuration from the statistical data storage unit 12 at an appropriate timing, and activates the disk control unit 6. During the execution of the application program for a predetermined time, this is a part for performing an operation of rearranging the writing position of the data on the recording surface so that the total seek movement amount for each data becomes smaller as a whole. For example, as shown on the left side of FIG.
It is assumed that the data 15 is distributed relatively widely on the upper side. In this case, if these data are alternately accessed, the total value of the seek movement amount of the head becomes very large. Therefore, by rearranging the data writing position,
As shown on the right side of the figure, the data 15 is collected in an appropriate empty area of the recording surface 7. This sufficiently reduces the seek movement amount when accessing these data.

If the seek movement amount is sufficiently small, the statistical data of the corresponding data is not required. In addition, the storage capacity of the statistical data storage unit 12 is preferably set to be sufficiently small for effective use of memory resources.
Therefore, it is preferable to store the statistical data as described above only for, for example, the seek movement amount that is relatively large. For this purpose, an appropriate reference value is set, and this is compared with the seek movement amount calculated each time. In this embodiment, the statistical data is stored only when the seek movement amount exceeds the reference value. The reference value of the seek movement amount is, for example, about one half of the distance from the beginning to the end of the recording surface of the hard disk.

When data having the same contents are accessed, a recording area for the number of accesses is provided in addition to the sector number 16, the data size 17, the seek movement amount 18. As a result, it is possible to efficiently collect and store statistical data for relocation of the data writing position.

FIG. 5 is an explanatory view of the seek operation and access time by the device of the present invention. First, it is assumed that the application program 1 requests the operating system 10 to access, for example, the access target file A or the access target file B before the data relocation control unit 13 shown in FIG. 1 operates. In this case, the head 9 performs a seek operation to access the data on the recording surface 7. In order to explain the seek operation of the head 9 in FIG.
The locus of the head 9 is shown by plotting the access position on the horizontal axis and the time on the vertical axis. In the first period T1 in this figure, the access monitoring unit 11 collects statistical data and stores the contents in the statistical data storage unit 12. Then, for example, when the device is shut down, the data relocation control unit 13 is activated. At this time, the dispersed data on the recording surface 7 are rearranged at positions close to each other in the same manner as described above with reference to FIG.

After that, when the apparatus is restarted, as shown in the second period T2 of FIG. 5, the seek distance of the head 9 is sufficiently smaller than that of the first period T1 in whole and on average. Become. As a result, even when the auxiliary storage device is frequently accessed, the access speed can be sufficiently improved as compared with the conventional case.

In the above embodiment, for example, when one application program accesses a plurality of access target files, the actual seek operation of the head is monitored, and the seek movement amount during the seek operation for a fixed time is determined. I aggregated and rearranged the data so that it was smaller. In this way, when a specific application program of the data processing device used for a specific purpose operates, the access time of the auxiliary storage device during the practical operation is sufficiently reduced to speed up the process. Can be achieved.

For example, if the application program is 1
When accessing only the individual files, it is sufficient to execute a process of collecting the data constituting the specific file to be accessed at a close location on the recording surface of the auxiliary storage device. However, an application program normally accesses a large number of files and executes a certain process. Therefore, even if the data belonging to the same file are rearranged so that the writing positions are close to each other, the total value of the seek movement amount does not always become small as a whole. Therefore, it can be said that it is more practical to actually aggregate the seek movement amount as in the present invention so as to efficiently rearrange data regardless of the number of files to be accessed.

The rearrangement of data as described above may be performed by, for example, finding an empty area of a track to be written at an appropriate position and moving data to be collected there. However, for example, a method of temporarily moving the data stored on one recording surface to another location and writing the data again based on an ideal rearrangement plan may be adopted.

Since the data relocation control unit 13 shown in FIG. 1 executes a process of moving the writing position of the data written in the auxiliary storage device 3 in this way,
The relocation operation is not performed while the application program 1 and other programs are running so as not to hinder the operation thereof. Therefore, after the entire device is shut down,
Alternatively, it is preferable that the device is started up and immediately before starting the work. It should be noted that if the execution condition of the data relocation control unit 13 is set at a priority level sufficiently lower than that of a large number of application programs and other programs operated by the apparatus, the apparatus can execute any program. When not in idle,
The data relocation control unit 13 can be automatically activated. In this case, the relocation work is performed in small steps. If another program is started, the rearrangement work may be temporarily stopped, and the apparatus may be restarted when the apparatus enters an idle state.

[0022]

In the data processing apparatus of the present invention described above, the access monitoring section monitors the access operation of the auxiliary storage device during execution of the application program, and the auxiliary storage device at the time of access operation of the auxiliary storage device is accessed for each data to be accessed. The statistical data storage unit stores the seek movement amount that the head seeks on the recording surface, and writes the data on the recording surface so that the total seek movement amount becomes smaller while the application program is executed for a predetermined time. Since the data relocation control unit relocates the position, the data is ideally placed on the recording surface of the auxiliary storage device, the seek movement amount of the head is reduced, and the access speed is improved. You can Therefore, it is not necessary to set a large-sized cache memory on the main storage device, and resources can be effectively used.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of a data processing device of the present invention.

FIG. 2 is a block diagram of a conventional data processing device.

FIG. 3 is an explanatory diagram of a conventional data transfer operation.

FIG. 4 is an explanatory diagram of statistical data.

FIG. 5 is an explanatory diagram of a seek operation and access time.

[Explanation of symbols]

 1 Application Program 3 Auxiliary Storage Device 6 Disk Control Unit 10 Operating System 11 Access Monitoring Unit 12 Statistical Data Storage Unit 13 Data Relocation Control Unit

Claims (1)

[Claims] 1. During execution of an application program,
An access monitoring unit that monitors the access operation of the auxiliary storage device, and a statistical data storage unit that stores the seek movement amount that the head seeks on the recording surface of the auxiliary storage device during the access operation for each data to be accessed. A data rearrangement that reads the statistical data storage unit and rearranges the writing position of the data on the recording surface so that the total seek movement amount becomes smaller while the application program is executed for a predetermined time. A data processing device comprising a control unit.