JPS61208119A - Disk controller - Google Patents

Abstract

PURPOSE:To eliminate a wait for writing in copying operation by copying a dual file by a magnetic disk controller and speeding up copying operation at the time of the fault recovery of the dual file. CONSTITUTION:Data read out of a normal magnetic disk device 6 are stored in a data buffer 3 in response to a copy indication between disk devices from a host and written in a fault recovery magnetic disk device 5, and when an indication of writing to the normal disk is made by the host during the copying processing, a control part 2 judges whether or not write addresses are addresses after the completion of the copying processing; when so, the addresses are stored in a rewrite address memory; 4 and the control part 2 copies the addresses of the rewrite address memory 4 again.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a disk control device that copies entire files in a duplex file system.

[Conventional technology]

Conventionally, when performing a full copy of this type of duplicated file during failure recovery, software has been used to prohibit writing to the file until the copying is completed.

[Problem that the invention seeks to solve]

In the above-mentioned method of full file copying using conventional software, the file is copied while being write-protected by software, so the write access to the file during that time is completely re-enabled, and as a result, the job This may cause a significant response delay, and if the file is shared by multiple CPUs, write access to the file is prohibited.
There is a drawback that there is a lot of complicated processing such as reporting between U units, which leads to a significant decrease in the throughput of the entire system.

The present invention provides an apparatus that solves the above problems.

[Failure to solve the problem]

The disk control device of the present invention has a data buffer that reads and stores copy data from a read-side magnetic disk device, and a write address (
One disk device of a dual-write disk device has a rewrite address memory that stores the cylinder number, track number), and a control unit that controls the magnetic disk device, host interface, data buffer, and rewrite address memory. When data is copied from the normal disk device to the disaster recovery disk device according to a copy instruction from the host between disk devices during failure recovery, the data read from the normal disk device is stored in the data buffer, and then the failure recovery is performed. When data is written to a disk device, and during the copy process there is an instruction from the host to write to the normal disk device, the control unit determines whether the write address is the address where copying has been completed, and if it is the address where copying has been completed. The present invention is characterized in that the address is stored in the rewrite address memory, and after the copying is completed, the address registered in the rewrite address memory is copied again in the control section.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

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

1 is a disk control device; 2 is a magnetic disk device; a host interface; a control unit that controls a data buffer and rewrite address memory (to be described later); 3 is a data buffer that stores copy data when copying data from the magnetic disk device to the magnetic disk device; is a rewrite address memory that stores the address (cylinder number, track number) when a write access is made to the magnetic disk device executing the copy during the copy operation. 5 and 6 are magnetic disk devices subject to dual writing; 101 is a host interface line for transferring various commands, data, status, etc. with the host; to2 and 103 are magnetic disk devices 5
, 6 and the disk controller 1, various instructions,
This is a device interface line that transfers data, status, etc. The magnetic disk drives 5 and 6 are dual-write disk drives (the same content is always written).

When the magnetic disk device 5 is disconnected from the system due to a failure and is incorporated into the system after the failure is repaired, the host issues a copy instruction from the magnetic disk device 6 to the magnetic disk device 5 to the disk controller 1 through the host interface line lot. It will be done.

In response to this instruction, the disk control device 1 uses the control unit 2 to read one track of data from the magnetic disk device 6 using the device interface line 103, writes it to the data buffer 3, and then writes it to the data buffer 3. Read the data stored in the device interface line 102.
data is written to the magnetic disk device 5 using the . Thereafter, the track numbers and cylinder numbers to be copied are sequentially changed and copied.

During this copy operation, the host interface 1
When the disk controller 1 receives an instruction to read or write to the magnetic disk device 6 through 01, the copy operation is interrupted and the instruction is performed. At this time, if the instruction is a write instruction, the control unit 2 It is determined whether the address (cylinder number, track number) where the copy process was completed is the address where the copy process was completed, and if it is the address where the copy process was completed, the rewrite address memory 4 is
Store that address in .

The control unit 2 controls the magnetic disk device 5 from the magnetic disk device 6.
Copy to maximum address (maximum cylinder, track)
When the contents of the rewrite address memory 4 are checked and an address that requires rewriting is registered, the address is transferred from the magnetic disk device 6 to the magnetic disk device 5 again.
Copy to.

The control unit 2 performs the above processing on all addresses registered in the rewrite address memory, and when all processing is completed, reports the completion to the host using the host interface 101.

〔Effect of the invention〕

As explained above, the present invention can speed up the copy operation when recovering a duplex file from a failure by processing the copy of the duplex file using a magnetic disk control device.
Furthermore, it is possible to eliminate the waiting time for writing during copying.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the present invention. 1... Disk control device 2... Control unit 3...
Data buffer 4... Rewrite address memory 5
．． 6...Magnetic disk device 101...Host interface lines 102, 103...Device interface lines Patent applicant NEC Corporation Figure 4

Claims (1)

[Claims] (1) In a disk control device that controls a dual-write disk device, there is a data buffer that stores data read from the disk device, and a write address (cylinder number, track number) to the disk device instructed by the host interface. ); and a control unit that controls the disk device, the host interface, the data buffer, and the rewrite address memory.