JPH05181618A - Peripheral controller - Google Patents

Abstract

PURPOSE:To improve the using efficiency of a floated head with the good bal ance secured on the entire surface of a disk by confirming the using frequency of a specific cylinder address set by the seek operations of the input/output instructions. CONSTITUTION:A patrol seek execution storage circuit 3 divides the general cylinder number of a magnetic disk device into blocks and at the same time stores a fact that a patrol seek operation is carried out for each block. Then the patrol seek operation is not carried out in a fixed period and at the same time the block having the least count value of a counter 2 is selected. The counter 2 counts the seek operations carried out by the input/output instructions. At the same time, the execution of the patrol seek operation is instructed to the cylinder address pointed by an address storage circuit 4 included in the selected block. As a result, the patrol seek operations are carried out in the order of cylinders having the lower using frequency.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a peripheral controller for controlling a magnetic disk device, and more particularly to a peripheral controller having a patrol seek function for improving reliability of the magnetic disk device.

[0002]

2. Description of the Related Art Conventionally, in order to realize a patrol seek function for a magnetic disk device, the seek operation of the patrol seek is not affected by the movement of the head or the like due to the seek operation instruction included in the input / output instruction. It is carried out by periodically wandering at a certain suitable cylinder pitch.

[0003]

In the patrol seek function by such a peripheral control device, the head movement due to execution of the seek operation command of the patrol seek is periodically performed at an appropriate seek pitch by the seek operation based on the input / output command. Since it is performed by wandering around, it is executed regardless of the frequency of use of a specific cylinder address, so it is the operation expected for the patrol seek function, which is the balance of the entire disk surface. There is a problem in that the efficiency is poor for the use of the levitated head that has been taken smoothly. Further, if the time period during which the patrol seek is operated on a certain disk surface is short, there is a possibility that all the disk surfaces cannot be used for floating the head.

[0004]

In order to solve such a problem, the present invention divides the total number of cylinders of a magnetic disk device into blocks and activates a seek command based on an input / output command for the cylinder address of each block. If there is, a counter that counts the number of each block, a patrol seek execution storage circuit that stores the execution of the patrol seek for each block, and an address storage circuit that stores the address at which the previous patrol seek was executed And a block selection circuit that selects from the patrol seek execution storage circuit the block in which the patrol seek is not executed within a certain period and the count value of the counter is the smallest, and the address storage circuit in the block selected by the block selection circuit. Patrol to instruct the cylinder address to execute patrol seek A seek instruction circuit it is for this patrol seek instruction circuit that provided a timer for instructing the patrol seek started every predetermined period.

[0005]

Therefore, the patrol seek is executed in order from the cylinder address which is less frequently used based on the seek operation of the input / output instruction. As a result, it is possible to efficiently perform the head floating use in which the entire disk surface is well balanced.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a peripheral control device according to the present invention. In the figure, the peripheral control device 1 is arranged between a central processing unit (not shown) and a magnetic disk device, has a patrol seek function, and is composed of the following parts. . That is, the total number of cylinders of the magnetic disk device is divided into a number of blocks, and when a seek instruction is started by an input / output instruction for the cylinder address of each block, a counter 2 for counting the number for each block and When the patrol seek is executed once for each block, and when this is completed, it is regarded as one round, and by remembering that the patrol seek was executed within this one round, the patrol seek for the same block is performed within that round. And the address storage circuit 4 for storing the cylinder address of the previous patrol seek for each block and notifying the cylinder address of the next patrol seek. And the counter 2 and the patrol seek execution memory circuit 3 Next, a block selection circuit 5 for selecting a block for which a patrol seek is to be executed, a patrol seek instruction circuit 6 for instructing a cylinder indicated by the block selection circuit 5 and the address storage circuit 4 to execute a patrol seek, and a patrol seek instruction circuit 6 And a timer 7 for instructing the start of patrol seek at regular time intervals.

Next, the operation of the peripheral control device 1 configured as described above will be described. When an input / output command including a seek command is given to the peripheral controller 1, the seek command is transmitted to the counter 2 via the signal line 8. Counter 2
Is a block in which the total number of cylinders of the magnetic disk device is divided into several blocks. When a seek instruction by an input / output instruction is executed, it recognizes which block the cylinder address is, and the counter corresponding to that block. Count up the count value of.

Further, in the counter 2, as a countermeasure against the overflow of the count value, the count values of all counters are reset even if any one of the counters overflows, and at the same time, they are stored in the respective counters at the same time. Priorities are given in ascending order of count value. This priority order is for determining the place where the seek operation by the I / O command is the least when the count values are the same or after resetting the count values or for a certain time (until the count values are accumulated). It is given.

Next, the operation of the entire apparatus will be described. The timer 7 instructs the patrol seek instruction circuit 6 to activate the patrol seek every predetermined time (seek pitch of patrol seek). The instructed patrol seek instruction circuit 6 causes the block selection circuit 5 to confirm the execution location of the patrol seek.

That is, the block selection circuit 5 selects from the counter 2 the block which is least sought by the input / output instruction. At this time, at the same time, it is confirmed from the patrol seek execution storage circuit 3 which block has performed the patrol seek within the round (when the patrol seek has been completed once for each block). If the patrol seek is performed within the round, the check is performed in the ascending order of the number of seek executions, and the block in which the patrol seek is not executed is searched.

In this way, the block selection circuit 5 reports to the patrol seek instruction circuit 6 the block in which the patrol seek is not executed within the round and the seek operation by the input / output instruction is the least. Upon receiving the report, the patrol seek instruction circuit 6 reads the cylinder address of the block from the address storage circuit 4 and executes patrol seek to the cylinder address. At the same time, the address storage circuit 4 updates the cylinder address of the read block to the cylinder address at which the next patrol seek is to be executed.

As described above, since the patrol seek is executed in order from the cylinder address which is less frequently used due to the seek operation of the input / output instruction, the head floating can be efficiently used in a balanced manner over the entire disk surface. it can. Further, even when the operation movement time of the patrol seek is short, the head moves randomly, so that it is possible to prevent the head from staying in a specific area.

[0013]

As described above, according to the present invention, since the patrol seek is executed in order from the cylinder address which is used less frequently due to the seek operation of the I / O instruction,
The head can be efficiently used for floating the head with a good balance over the entire disk surface.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a peripheral control device according to the present invention.

[Explanation of symbols]

 1 Peripheral control device 2 Counter 3 Patrol seek execution storage circuit 4 Address storage circuit 5 Block storage circuit 6 Patrol seek instruction circuit 7 Timer 8-12 Signal line

Claims (1)

[Claims] 1. A peripheral controller for controlling a magnetic disk device, which has a patrol seek function, divides the total number of cylinders of the magnetic disk device into blocks, and activates a seek command based on an input / output command for a cylinder address of each block. If there is a counter, a counter that counts the number of each block, a patrol seek execution storage circuit that stores the execution of the patrol seek for each block, and an address storage that stores the address at which the previous patrol seek was executed A circuit, a block selection circuit that selects from the patrol seek execution storage circuit the block in which the patrol seek is not executed during a certain period and the count value of the counter is the smallest, and the block in the block selected by the block selection circuit. Cylinder address indicated by the address storage circuit Peripheral controller, wherein the patrol seek instruction circuit for instructing a patrol seek execution, further comprising a timer for instructing the patrol seek started every predetermined period with respect to the patrol seek instruction circuit.