JPH06139025A - Search key command processing method at the time of multitrack operation designation - Google Patents

Abstract

PURPOSE:To prevent the deterioration of the processing efficiency of a magnetic disk even when a switching to the track of a different cylinder at the time of a search command processing by releasing the connection of a magnetic disk controller with the magnetic disk when a track positioning accompanying the movement of the cylinder occurs. CONSTITUTION:When the command of processing the search command over the plural tracks is issued from a processor 1, and the positioning of the track accomapanied by the movement of the cylinder occurs during the search operation, the connection of a magnetic disk controller 2 with a magnetic disk 3 is released. Therefore, the magnetic disk controller 2 can execute the other processing. The magnetic disk controller 2 commands the positioning of the track of the other cylinder to the magnetic disk 3. Then, when the positioning is ended, it is informed to the magnetic disk controller 2 by an interruption, and the magnetic disk controller 2 is connected with the magnetic disk 3, and the search is started.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for searching key data from a magnetic disk in a data processing system,
In particular, it relates to a search key command processing method when a multi-track operation is designated.

[0002]

2. Description of the Related Art A record of data on a magnetic disk is
In addition to the data to be recorded, a key portion indicating a record indicator and a count portion indicating a record address such as a flag, a cylinder number, and a head number are added and recorded.

In data processing, a magnetic disk is often searched by using the key number of the key portion as a search target. A conventional example of a magnetic disk search method in which such a key number is searched will be described with reference to FIGS. Although FIG. 2 is a configuration diagram of the embodiment of the present invention, since the configuration of the conventional example is the same in terms of hardware, FIG. 2 will be referred to. Further, FIG. 4 is an operation explanatory diagram of a conventional example.

In the explanation of the operation, the case where the processor 1 causes the magnetic disk controller 2 to retrieve the record of a certain key number from the records recorded between the tracks N and N + 2 of the magnetic disk 3 will be described. An example will be explained. Further, in this case, it is assumed that the tracks N and N + 1 are in the same cylinder and the track N + 2 is in another cylinder. Reference numeral HA indicates a home address portion, C indicates a count portion, K indicates a key portion, and D indicates a data portion.

As described above, when the search key command is issued from the processor 1 to the magnetic disk control device 2 with the multi-track operation designation, the magnetic disk control device 2 causes the magnetic disk 3 to read the first track. The head positioning is commanded to the first record of N, and when the positioning is completed, the magnetic disk controller 2 and the magnetic disk 3
4, are combined, and as shown in FIG. 4, the last record n + 1 is sequentially read from the first record 1 to search whether the key number recorded in the key portion K is a designated value.

If no track N is found, the head is switched to the next track N + 1. In this case, since the track N and the track N + 1 are in the same cylinder, the pair processing is performed only by switching the heads, and the search is continued.

If no key is found in the track N + 1, the next track N + 2 is selected. In this case, since the cylinder of the track N + 2 is a cylinder different from the track N + 1, by the time the search is started from the track N + 2, after the positioning of the head to the track and the positioning of the head to the first record are completed, the search is performed. Is resumed.

[0008]

As described above, when the search key command is issued in the conventional multi-track operation designation, the heads are switched to the tracks of different cylinders as described with reference to FIG. Even in
The magnetic disk control device and the magnetic disk were in a coupled state.

When the head is switched to the track of a different cylinder, it takes a very long time because of waiting for the rotation of the disk for mechanical operation and cueing. That is, since it is occupied, other processing cannot be executed, and the processing efficiency is reduced.

The present invention has been made to solve the above problem, and has been improved so that the processing efficiency of the magnetic disk controller is not deteriorated even when the tracks of different cylinders are switched during the processing of the search key command. It is an object to provide a search key command processing method when a multi-track operation is designated.

[0011]

Means adopted by the present invention for solving the above problems will be described with reference to FIG. According to the search key command processing method of the present invention, in a magnetic disk control device for processing a search key command across a plurality of tracks, when the track positioning accompanied by the movement of the cylinder during the search operation occurs (process 11), the magnetic disk is processed. The controller is disconnected from the magnetic disk (process 12), and when the positioning is completed (process 13), the magnetic disk controller and the magnetic disk are re-coupled (process 14) again.

[0012]

When the processor constituting the data processing system is instructed to process the search key command over a plurality of tracks and the positioning of the track accompanied by the movement of the cylinder occurs during the search operation, the magnetic disk control is performed. Release the connection between the device and the magnetic disk. Then, the track positioning operation is performed with the coupling released, and when the positioning is completed, the magnetic disk controller and the magnetic disk are coupled again and the search operation is continued.

As described above, when the track positioning accompanied by the movement of the cylinder occurs during the search operation while the search key command is being executed over a plurality of tracks, the magnetic disk is replaced with the magnetic disk until the track positioning is completed. Since it was separated from the control device,
Other processing can be executed during the separated period, and the processing efficiency of the magnetic disk control device can be improved.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to FIGS. 2 is a block diagram of the embodiment of the present invention, and FIG. 3 is an operation flowchart of the embodiment.

In FIG. 2, 1 is a processor, 2 is a magnetic disk controller, 21 is a controller, and 3 is a magnetic disk. When the search key command is issued from the processor 1 by specifying the multi-track operation, the processing based on the operation flowchart shown in FIG. 3 is performed.

Process S1 In process S1, the controller 21 of the magnetic disk controller 2 issues a command to position the first commanded track.
More emitted to the magnetic disk 3.

Step S2 In step S2, the magnetic disk 3 positions the track instructed in step S1, and when the positioning is completed, the magnetic disk controller 2 is notified of the completion of positioning by an interrupt.

Process S3 When the magnetic disk control device 2 receives the positioning completion notification from the magnetic disk 3, the magnetic disk control device 2 and the magnetic disk 3 are connected and the key search is started.

Steps S4, S5 and S12 In step S4, a record is read from the magnetic disk 3, and in step S5 it is determined whether or not the keys match. If the determination result is YES, the process moves to step S12 to access the data. And the process ends. If the determination result is NO, the process proceeds to step S6.

Process S6 In process S6, it is determined whether or not the record determined in process S5 is the last record recorded on the track. If NO, the process proceeds to process S4 and the process for the next record is performed, and YES. In case of, it moves to the processing S7.

Process S7 In process S7, it is determined whether or not there is a track to be searched next. If YES, the process proceeds to process S8, and if NO, the process ends.

Steps S8 and S9 If there is a next track to be searched in the step S7, it is judged whether or not the next track to be searched is a track existing in another cylinder. If NO, that is, the same cylinder. If the track exists in step S9, the head is switched in step S9, and the process proceeds to step S4 to perform the search process. If YES, the process moves to step S10.

Process S10 In process S10, the coupling between the magnetic disk controller 2 and the magnetic disk 3 is released. Therefore, the magnetic disk control device 2 can execute other processing, and executes the processing.

Process S11 In process S11, the magnetic disk control device 2 commands the magnetic disk 3 to position another cylinder on the track, and then proceeds to process S2. When the positioning is completed in the process S2, the magnetic disk controller 2 is notified by an interrupt, and the magnetic disk controller 2 and the magnetic disk 3 are combined in the process S3 to start the search.

Therefore, from the processing S11 to the processing S3, the magnetic disk controller can be released from the processing of the search key command and can execute other processing, and the processing efficiency can be improved.

Although one embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and various modifications can be made according to the gist of the invention.

[0027]

As described above, according to the present invention, the following effects can be obtained. When the track key positioning occurs due to the movement of the cylinder during the search operation while executing the search key command over multiple tracks, the magnetic disk is disconnected from the magnetic disk controller until the track positioning is completed. The other processing can be executed during the separated period, and the processing efficiency of the magnetic disk control device can be improved.

[Brief description of drawings]

FIG. 1 is a principle diagram of the present invention.

FIG. 2 is a configuration diagram of an embodiment of the present invention.

FIG. 3 is an operation flowchart of the same embodiment.

FIG. 4 is an operation explanatory diagram of a conventional example.

[Explanation of symbols]

 1 processor 2 magnetic disk controller 3 magnetic disk

Claims (1)

[Claims] 1. In a magnetic disk controller for processing a search key command across a plurality of tracks, when track positioning accompanied by movement of a cylinder occurs during a search operation, the magnetic disk is controlled until the track positioning is completed. A search key command processing method when a multi-track operation is specified, characterized by being separated from the magnetic disk controller.