JPS6034128B2 - magnetic disk controller - Google Patents

Description

[Detailed description of the invention] The present invention relates to a magnetic disk.

In particular, it relates to a control method for record search operations. Conventionally, in a search operation for a written record, this type of magnetic disk control device compares the identification part of the read record with the search information containing the contents of the identification part of the target record, and if they do not match, the process continues. Continuing the comparison by including the identification part of the record.

However, during this time, the magnetic disk control device is in a state where it is exclusively used for search operation processing. In particular, when the data portion of records that do not match is long, the efficiency of using the magnetic disk control device is reduced. The present invention improves on this point, and allows processing of other magnetic disks to be performed in parallel while the data section is being read during a search operation, thereby improving the efficiency of use of the device. The purpose is to provide equipment.

The present invention provides a magnetic disk control device that is controlled to read a record identification section of a record recorded on a magnetic disk recording medium and perform a search operation by comparing it with search information. A first means of determining whether the record length of the mismatched record is longer than a predetermined reference value when there is a mismatch with the above search information, and a second means of determining whether the record length of the mismatched record is longer than a predetermined reference value. A second means for calculating the rotation angle position at which the record should exist, and a third means for storing the result calculated by the second means and the search information in a storage area corresponding to the magnetic disk. , suspending the search operation for the magnetic disk device until the read/write head of the magnetic disk device reaches around the rotation angle position stored in the third means to enable processing to other magnetic disk devices; ,
The present invention is characterized in that when the read/write head reaches near the rotation angle position stored in the third means, the search operation for the magnetic disk device is resumed.

In the present invention, when a search operation for a record identification section is unsuccessful, the data length of this record is compared with a preset standard, and if the data length exceeds this standard, the data length of this record is determined based on the current rotational angle position and the data length of this record. The rotation angle position where the next record should exist is calculated, and the calculated rotation angle position and search information are temporarily stored until the read/write head of the magnetic disk device reaches the next record position. It is characterized in that it is configured to concurrently perform processing on other magnetic disk devices.

This allows other magnetic disk devices to perform processing even during a search operation. An embodiment of the present invention will be described based on the drawings.

The figure is a block diagram of main parts of an embodiment of the present invention. In the figure, the system is roughly divided into a central processing unit 1, a magnetic disk control device 2, and a magnetic disk device 3. That is, the control section 5 in the magnetic disk control device 2 is connected to a storage section 6 that stores a microprogram.

Also connected to this control section 5 is a storage section 7 that stores search information indicating the rotational angular position and the contents of the target record identification section for each magnetic disk device 3. Further, a data transfer section 8 connected to the central processing unit 1 is connected to the control section 5. An adapter section 9 is connected to these data transfer section 8 and control section 5. A magnetic disk device 3 is connected to this adapter section 9 . With such a configuration, the microprogram stored in the storage unit 6 is read by the control unit 5, and by controlling the data transfer unit 8 through the control unit 5, it is connected to the magnetic disk device 3 and the central processing unit via the adapter unit 9. Controls data transfer to and from the device 1.

Now, when the control unit 5 receives a search operation command for a record on a magnetic disk recording medium together with search information from the central processing unit 1, the identification section of the record is read from the magnetic disk device 3 and compared with the search information.

If they do not match, the control section 5 checks whether the data length indicated in the read record identification section exceeds a preset reference value. When the data length exceeds this reference value, the current rotational angular position is read and the rotational angular position where a record based on the above data length should exist is calculated using the following equation. 8=Q, where the rotation angle position where the next record should exist, Q', the current rotation angle position, d
represents the data length, and D represents the data length for one rotation.

Next, from the calculated rotational angle position 8, sufficient time to scan the states of all the connected magnetic disk drives and the rotational angle corresponding to the error in this calculation are subtracted, and this is stored in the storage unit 7 along with the search information. Store in the area corresponding to the magnetic disk device that is being executed.

Next, the microprogram in the storage unit 1 causes the control unit 5 to
interrupts the search operation in progress and switches to processing of another magnetic disk device 3.

When the process is connected to the original magnetic disk device 3 again, the current rotation angle position is read from the magnetic disk device 3, compared with the rotation angle position previously stored in the storage unit 7, and a match or difference is searched. When it is determined that the operation is within the operation restart range, search information is retrieved from the storage unit 6, the search operation is restarted, and the identification section of the next record is searched. Note that if the data length does not exceed the set standard, the search operation continues as is. As explained above, when the search operation of a magnetic disk device is unsuccessful, the rotation angle position where the next record should exist is calculated from the data length and the current rotation angle position, and this calculation result is The search information is stored in a storage area corresponding to the magnetic disk device, and the search operation is interrupted.

After that, processing of other magnetic disk devices is performed. When this control device is reconnected to the magnetic disk device where the search operation was interrupted, it also compares the above stored contents with the current rotational angle position, and if this is determined to be within the search operation restart range, it performs the search operation again. I decided to search for the identification part of the next record. Therefore, during the search operation of one magnetic disk device as in the conventional device, even if the search operation is unsuccessful, the control device is not monopolized until the search operation is completed, and other magnetic disk devices are Disk device processing can be performed in parallel. For this reason,
The usage efficiency of the magnetic disk control device can be significantly improved. Furthermore, it has the effect of improving the processing efficiency of the entire system.

[Brief explanation of drawings]

The figure is a block diagram of main parts of an embodiment of the present invention. 1... Central processing unit, 2... Magnetic disk control device, 3... Magnetic disk device, 5...
・Control unit, 6, 7... Storage unit, 8...
Transfer section, 9...adapter section.

Claims (1)

[Claims] 1. In a magnetic disk control device that is controlled to read a record identification section of a record recorded on a magnetic disk recording medium and perform a search operation by comparing it with search information, the read record identification section reads the above search information. a first means for detecting whether the record length of the mismatched record is longer than a predetermined reference value when the record length is longer than a predetermined reference value; and a third means for storing the result calculated by the second means and the search information in a storage area corresponding to the magnetic disk. The search operation for this magnetic disk device is interrupted until the read/write head of the device reaches around the rotation angle position stored in the third means, and processing for another magnetic disk device is enabled, and the read/write operation is performed. A magnetic disk control device characterized in that the magnetic disk control device is configured to restart the search operation for the magnetic disk device when the loaded head reaches around the rotation angle position stored in the third means.