JP2576805B2 - Disk controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk controller, and more particularly to a disk controller capable of generating information necessary for performing file relocation control in order to level input / output (I / O) wait times of a plurality of disk devices. It concerns the device.

[0002]

2. Description of the Related Art When a plurality of disk devices are used by a host device as a plurality of hosts, if I / O processing is concentrated on files on a specific disk device, the
A standby time occurs in the O operation, and a response of the online processing and a delay in the processing time of the patch job occur, thereby reducing the operating rate of the system.

In order to prevent a reduction in the operation rate of such a system, it is necessary to relocate files between disk devices so that I / O is not concentrated on a specific disk device. As a method of such file relocation, a computer operation staff investigates the disk unit's busy rate from system operation information, and relocates a file of a disk unit with a high busy rate to a disk unit with a low busy rate. There is a way to do that.

Also, with reference to Japanese Patent Application Laid-Open No. 3-171352, the number of I / Os of peripheral devices being executed is counted by a counter, and an I / O responding to a command from a higher-level device is counted.
At the start of / O, a configuration is shown in which a peripheral device having a small counter value is selected to execute I / O of this peripheral device, and the value of the counter is incremented by one. That is, I / O
Are counted, and the counted value is used as system operation information.

[0005]

In the method of using the busy rate as the system operation information of the disk device, if the busy ratio of the disk device is high, the I / O standby time becomes longer, and the system operating ratio decreases. The file is rearranged based on the ratio. However, when a specific host device continuously accesses a specific file, the I / O standby time may not occur even if the busy ratio is high. The disadvantage is that file relocation based on rate is not accurate.

In the case where the number of I / O executions disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 3-171352 is used as the system operation information, even if the number of executions is large, the above-mentioned specific host device is specified. When the file is accessed continuously, there is no I / O waiting time, so that there is a disadvantage that this is not accurate.

Therefore, the present invention has been made to solve the above-mentioned drawbacks of the prior art, and an object of the present invention is to use the I / O standby time itself as the system operation information and reduce the I / O standby time. It is another object of the present invention to provide a disk control device which enables a computer administrator to perform accurate file relocation management.

[0008]

According to the present invention, there is provided a disk controller which receives a command from a higher-level device and controls input / output to a plurality of disk devices. A standby time calculating means for calculating a standby time until the start of input / output to / from the device, and an average value of the standby times for the respective disk devices by integrating the standby times for a predetermined period based on the calculated standby time. Means and a means for reporting the average value of the waiting time in accordance with an instruction from the higher-level device.

Further, according to the present invention, there is provided a disk control device further comprising means for notifying the host device when the average value of the standby time exceeds a preset value. Can be

[0010]

The I / O standby time from the reception of a command from the host device to the start of input / output to the disk device is calculated using a clock counter or the like, and is fixed based on the calculated I / O standby time. The standby time in the period is integrated to calculate an average value of the standby time for each disk device. If this average value is reported to the higher-level device, the higher-level device can know the average value of the I / O standby time for each disk device, and the computer operation manager can use this average value to accurately determine the file relocation. Can be performed.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of a disk control device used in the present invention. The disk control device 2 normally receives commands (commands) from a plurality of higher-level devices 1
According to the command received by the I / O control unit 3 and the disk I / O control unit 12, a plurality of disk devices 13 to
16 and a plurality of higher-level devices 1.

The counter 7 is a multi-bit counter that counts up at regular intervals and indicates the passage of time. I / O
After receiving the command reception signal 6 from the higher-level I / O control unit 3, the standby time calculation unit 10 sets the disk I / O control unit 12
The time until the disk I / O start signal 11 is received from the counter 7 is calculated from the value of the counter 7 and output to the average value calculation unit 9.

The average value calculator 9 is an I / O standby time calculator 1
The I / O standby time for each command received from 0 is totaled, and the average value of the I / O standby time for each disk within a fixed time is calculated.

When the I / O standby time report unit 5 receives an I / O standby time read command from the host device 1 through the host I / O control unit 3, the I / O standby time report unit 5 sends the I / O standby time read command from the average value calculation unit 9 to the I / O standby time for each disk device. The average value of the I / O standby time is read, and the average value is reported to the host device 1 through the host I / O control unit 3.

The I / O standby time comparing section 8 always compares the preset comparison value with the average value of the I / O standby time output from the average value calculating section 9, and this average value exceeds the comparison value. Then, the I / O standby time excess notifying unit 4 is notified of the number of the disk device that has exceeded.

When the I / O standby time excess notifying unit 4 is notified of the disk device number from the I / O standby time comparing unit 8,
Via the upper I / O controller 3, the upper device is notified of the excess of the I / O standby time and the number of the excess disk device.

By doing so, the computer operation manager can know the average value of the I / O standby time and the state where the average value is extremely large for each disk device as the system operation information. I /
The file can be rearranged so that the average value of the O waiting time is uniformly reduced.

[0019]

As described above, according to the present invention,
Since the disk controller is provided with a means for calculating and reporting the I / O wait time, it is possible to accurately relocate the file based on the I / O wait time, and further to confirm that the I / O wait time has reached a certain level or more. Providing the means for detecting and notifying has an effect that the cause at the time of a decrease in the system operation rate can be immediately investigated.

[Brief description of the drawings]

FIG. 1 is a system block diagram of an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper apparatus 2 Disk controller 3 Upper I / O control part 4 I / O standby time excess notification part 5 I / O standby time report part 7 Counter 8 I / O standby time comparison part 9 Average value calculation part 10 I / O Standby time calculation unit 12 Disk I / O control unit 13-16 Disk device

Claims (3)

(57) [Claims] 1. A disk control device for performing input / output control on a plurality of disk devices in response to a command from a higher-level device, wherein a standby time from when a command is received from the higher-level device to when input / output to a disk device is started. A standby time calculating unit that calculates the average value of the standby time for each disk device by integrating the standby time in a certain period based on the calculated standby time; and Means for reporting in accordance with an instruction from the higher-level device. 2. The disk control device according to claim 1, further comprising means for notifying the host device when the average value of the standby time exceeds a preset value. 3. The waiting time calculating means includes means for counting time, and means for calculating a waiting time from when the command is received to when input / output to a disk device is started with reference to the timed content of the time counting means. 2. The method according to claim 1, further comprising:
Or the disk controller according to 2.