JPS6238928A - Seek control system for storage system - Google Patents

Abstract

PURPOSE:To reduce a load on a controller and to improve the efficiency of a system by allowing the controller to decode a block number when receiving an end signal and reading an ID number and then reporting the end to a host after delaying by the time based upon the relative position relation with a target block. CONSTITUTION:The MPU 20 of the controller 2 reads an ID number from the head of a memory device when receiving a seek end signal from the memory device through a drive control part 23. A counter 24 is set to an initial value D and a start signal is supplied to the counter 24 to make a preset start. Consequently, the counter 24 begins to count a clock CL and a flip-flop 25 is set with a carrier output. An end signal SKC generated by the setting of this flip- flop 25 is sent as an interruption to the MPU 20, which interrupts other processes and reports the end to the host 1 through a host interface 22. Further, the MPU 20 resets the flip-flop 25 with a reset signal RSKC.

Description

[Detailed Description of the Invention] [Table of Contents] Overview Industrial Application Fields Conventional Technology Problems to be Solved by the Invention Means for Solving the Problems (Fig. 1) Functional Example Fat - Structure of the Example Explanation (Fig. 2) fbl - Explanation of the operation of the embodiment (Fig. 3) tel Explanation of other embodiments Effects of the invention [Summary] The controller controls the storage device according to instructions from a higher level to store rotational storage. In a storage system that performs recording/reproduction on a medium, the efficiency of the upper layer and the controller can be improved by delaying the seek completion report from the storage device until just before the head of the storage device reaches the target block. It was designed to improve the performance.

[Industrial application field]

The present invention relates to a seek control method that delays the timing of a seek completion report due to a seek operation and improves system efficiency in a storage system including a storage device having a rotating storage medium such as an optical disk or a magnetic disk.

Storage devices using rotating storage media such as optical disks and magnetic disks are widely used as external storage devices for computers.

In a storage system using such storage devices, as shown in FIG. 4, a channel (upper level) 1 of a computer that issues access requests, read/write commands, etc. is connected to a controller 2, and the controller 2 controls a plurality of storage devices 3a to 3a. Storage devices 3a to 3 configured to be connected to 3n and targeted by the controller 2 according to instructions from the upper level 1.
By controlling n, data is recorded or reproduced on the rotating storage medium of the storage devices 3a to 3n, and write data is recorded from a higher level or read data is transferred to a higher level.

[Conventional technology]

As shown in FIG. 5(A), the rotary storage medium has tracks T1 to Tn arranged concentrically on a disk 30, and a recording/reproducing head (not shown) moves in the radial direction and is positioned at a desired trunk. On the other hand, each track is written (recorded) in block units, and as shown in FIG. 5(B), an ID number area is provided at the beginning of one block in which the track number and block number are recorded. Subsequently, a data area is provided and configured.

The trunk pinch of such a rotating storage medium 30 tends to be minimized, and in optical disks, the inter-track pinch is 2.5
4. Extremely high-density information recording with a focus distance of 1.6 microns, reaching 1.6 microns. a is possible. or,
On an optical disc, the TD number is created in advance by preformatting, and can normally be recorded only in the data area.

In order to paste/write a desired block, it is necessary to move the head in the radial direction, position it on the desired trunk, and then wait until the block arrives at the head position by rotation of the disk 30. be.

Therefore, in order for the higher level to access a desired data block on a desired trunk of the rotating storage medium, as shown in FIG. Then, in response to the response from the controller 2, the higher rank 1 transmits the target track and target block.

(2) Upon receiving this, the controller 2 issues a channel end signal CHE to the higher level 1 and releases the connection with the higher level 1. As a result, the upper level 1 becomes free, and the upper level 1 can perform other processing (for example, communication with other controllers, etc.).

(2) On the other hand, the controller 2 instructs the specified storage device to move the head to the target track (seek operation).

After this, the device a operates alone, and the controller 2 becomes free to perform other processing.

■Note 1. In device a, when the head is positioned on the target trunk, the seek operation is performed successfully), and when the seek to the target track is completed, a completion signal is reported to the controller 2.

(2) When the controller 2 detects the completion signal, it reads the ID number from the head of the storage device, and if the 10 number matches the target trunk, it determines that it is on track, and the controller 2 reports that the head positioning to the upper 1 is completed.

(2) The upper I then issues a read/write command to the target block.

■The controller 2 continues the I
The storage device reads the D number (block number), receives the IF') number and determines whether it is the target block, and when it is determined that the target block has been reached, it instructs the storage device to read or Begin processing lights.

[Problem that the invention seeks to solve]

In such a conventional technique, in step (3), the controller 2 needs to read the block number from the storage device and perform a block search until the target block is reached.

For example, if one block is 1 ma and one rotation is 60 ma, a maximum of 60 m5 will be spent on this, and during this time the controller 2 will be exclusively used for block search (rotation waiting) processing and will not be able to perform other processing, resulting in poor efficiency. was alive.

SUMMARY OF THE INVENTION An object of the present invention is to provide a seek control method for a storage system that can reduce the burden on a controller and improve system efficiency.

[Means for solving problems]

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

In the present invention, when the controller 2 receives the completion signal and reads the ID number in the above-mentioned step (3), it decodes the block number, and after a delay of time based on the relative positional relationship with the target program, the controller 2 receives the completion signal and reads the ID number. A completion report is issued at 1.

That is, the block search operation after receiving the completion signal is not started from the reception of the completion signal.

[Effect]

In a rotating storage medium, the time required for one block is fixed, so in the present invention, the rotational position of the storage device at the time of receiving the completion signal is determined by the controller 2 based on the block number.
detects the target block 1, (to the head)
By predicting the arrival time, delaying the completion report by that time using a timer, etc., and starting the block search and read/write processing using the read/write command from the -most position, the minimum block search is possible.

This reduces the time required to read the block number, thereby significantly reducing the burden on the controller 2 and increasing efficiency.

Moreover, this can be realized without providing a block position detection mechanism on the storage drive side.

〔Example〕

[81 Explanation of the configuration of an embodiment FIG. 2 is a configuration diagram of an embodiment of the present invention.
2 shows the internal configuration of the troller 2.

- In the figure, 20 is a microprocessor (hereinafter referred to as MPU), which constitutes the main control section of the controller 2, performs selective operations according to instructions from the upper level 1, and controls the storage device; This is done by executing a control program. 21 is a control storage that stores the control program, parameters, etc. of the MPU 20. 22 is a host interface that exchanges signals with the host. 23 is a device control unit which performs operation of the device 1a and read/write control according to instructions from the MPU 20.

24 is a counter, in which the initial value from the MPU 20 is sent, and the start signal *5TART from the MPU 20 is sent.
25 is a flip-flop that counts the clock CL, and the start signal of M P IJ 20 *
It can be set by 5TART, and the carry output of the power counter 24 is set by the clock CL to notify the MPU 20 of the seek end SKC interrupt.
PU 20 is reset by the set signal R3KC, and 26 is an inverter that inverts the carry output of the counter 24 and inhibits the counting operation of the counter 24.

In this embodiment, M
In addition to the PU 20, control storage 21, upper-level interface 22, and device control unit 23, a counter 24, a flip-flop 25, and a part of a timer such as an inverter 26 are added.

(bl-Description of the operation of the embodiment FIG. 3 is an explanatory diagram of the operation of one embodiment of the present invention.

The seek operation of the storage device from the access request from the upper level 1 is the same as the conventional steps (1) to (4).

■When the MPU 20 of the controller 2 receives a seek completion signal from the storage device via the drive control unit 23,
Read the ID number from the head of the storage device. At this time, if it is b in FIG. 5(A), the controller 2 confirms that b is a block on the target track Tm, and determines that the block is on-track.

■If the target block is a, then C in Figure 5 (A)
If it is appropriate in terms of the performance of the first-level device that the completion report is given to the first-level device at the position of MPU 20 calculates. and,
Set the initial value to the counter 24 and start signal *5
Apply TART to the counter 24 to start preset.

(2) As a result, the counter 24 starts counting the clock CL and sets it in the flip-flop 25 by the carry output. At this time, in the storage device, the head position has reached the tip of the block C, and while waiting for this rotation, the MP
U20 becomes free and can execute other processing.

■The termination signal by the seven nodes of this flip-flop 25 (
The time over signal) SKC is notified to the MPU 20 as an interrupt, and the M P IJ 20 interrupts other processing and reports the completion to the higher level 1 via the higher level interface 22 as in step (2). Along with this, M
The PU20 sends the flip-flop 25 by the send signal R3KC.

The subsequent operation is similar to step (2), in which a read/write command for the target block is received from the upper level 1, and a read or write process for the target block a subsequent to block C is executed via the device control unit 23.

In this way, by delaying the completion report by the time based on the relationship (difference) between the rotational position (block position) and the target block position during the seek operation and the performance factors required for response to the higher order, A search operation can be omitted, and when a read/write command is received from the top 1, the head of the storage device can be made to correspond to the vicinity of the target block.

That is, the controller 2 predicts the rotational waiting time until the target block reaches the vicinity of the head from the block when the head is on track, stops the block search during this time, and executes other processing. .

Furthermore, the time period in which the top 1 is free is extended, and the processing is not interrupted as in the conventional case.

(C1 Description of Other Embodiments In the above-described embodiments, a timer using a hardware counter is provided, but the timer may be implemented using a software timer instead of this.

Although the present invention has been described above using one embodiment, the present invention can be modified in various ways according to the gist of the present invention, and these are not excluded from the present invention.

〔Effect of the invention〕

As described above, according to the present invention, the time required for the block search by the controller is shortened, and the idle time period of the controller is increased. Therefore,
The busy rate of the controller is reduced and efficient operation is possible. Further, it can be realized without adding any special configuration to the storage drive side, and can be realized by adding some configuration to the controller side, so that the system efficiency can be easily improved. Furthermore, since it is only necessary to change the conventional control procedure, it can be easily implemented into a system, which is an excellent practical effect.

[Brief explanation of the drawing]

FIG. 1 is a diagram explaining the principle of the present invention, FIG. 2 is a configuration diagram of an embodiment of the invention, FIG. 3 is a diagram explaining the operation of an embodiment of the invention, FIG. 4 is a configuration diagram of a storage system, The figure is an explanatory diagram of a rotating storage medium, and FIG. 6 is an explanatory diagram of a conventional technique. In the figure, 1- upper level, 2- controller, 3a to 3n- storage device, 30- rotation record 4. a medium.

Claims (2)

[Claims] (1) A higher-level device that issues access requests and read or write commands, a storage device that seeks the head for recording or playback on a rotating storage medium, and performs a recording or playback operation on a specified block, and a storage device that issues an access request and a read or write command, and and a controller that controls the storage device in response to the access request, and the controller instructs the storage device to seek to a target track in response to the access request, and in response to a seek completion report from the storage device, the controller controls the storage device in response to the access request. In a storage system that reports the end of a seek to a host and starts recording or playback processing upon receiving a command from a higher level, the controller receives the block number of the seek position from the storage device when receiving the seek completion signal. A seek control method for a storage system, wherein execution of the seek end report is delayed for a time based on the relative positional relationship between the instructed target block number and the received block number. (2) The controller includes a timer in which a time is set based on the relative positional relationship, and executes the seek completion report when the timer times out. Seek control method for storage system.