JPH01133132A - Interruption system for filing device - Google Patents

Abstract

PURPOSE:To improve the using efficiency of a bus channel without generating overhead by connecting a timing setting part so that the data transfer start timing of a reading system coincides with that of a writing system. CONSTITUTION:A filing device 12 provided with a storage means such as a disk mechanism 18 includes as intellectualized interface 14 for receiving an access request from a host device 10 and executing access control by a microprogram. The timing of a reconnection interruption request to be led in the host device 10 so that the data transfer start timing of the reading system coincides with that of the writing system is set up by an interruption timing setting part 16. An added result (d) of the number (a) of sectors indicating a sector position setting up a reconnection interruption request and a value (b) indicating a current sector position is compared with the objective number (c) of sectors, and when both the values coincide with each other, the reconnection interruption request is led.

Description

[Detailed Description of the Invention] [Summary] Regarding the file device interrupt method that raises a recombination interrupt request for data transfer after separation from the host device due to access completion, this occurs in either the REIT system or the write system. In order to eliminate overhead and improve bus channel usage efficiency, the timing of recombination interrupt requests is set so that the start timing of read and write data transfers is the same.

[Field of Industrial Application] The present invention relates to an interrupt method for a file device that raises a recombination interrupt request for data transfer after disconnection from a host device due to completion of access.

In recent years, file devices such as magnetic disks are becoming more intelligent through the adoption of standard interfaces and microprograms.

[Prior Art] FIG. 5 is an explanatory diagram of a conventional system equipped with a magnetic disk as a file device.
B is connected via a standardized and intelligent intelligent interface 14. When the file device 12 receives an access request from the host computer 10a, the intelligent interface 1
4 is the disk mechanism 1 corresponding to the microprogram
8 is activated under access control, and upon completion of access, a separation process is performed to release the bus with the host computer 10a. Then, when the sector pulse of the disk mechanism 18 reaches a certain sector position before the target sector, the intelligent interface 14 transfers the data to the post computer 10a.
A reunion interrupt request is launched and host computer 1
It waits for input of a response message from 0a and starts data transfer for reading or writing.

Specifically, in the case of the standard interface currently in use, this is done by causing the file device to initiate a recombination phase with the host device when the file device reaches a sector position a certain number of sectors before the target sector after separation. The higher-level device that decoded this recombination phase notifies the file device of a response message, thereby starting data transfer.

By adopting such a standard interface and making it intelligent, the interface of the file device can be shared, and the load on file channel control can be reduced, among other benefits.

In addition, by adopting a standard interface, file devices can be commonly connected to appropriate host computers, but since the performance of host computers varies, recombination requests can be made depending on the performance of the host computer, as shown in Figure 6. The interrupt timing can be changed.

Figure 6(a) shows the case of a high-performance host, and Figure 6(b) shows the case of a high-performance host.
indicates the case of a host with poor performance.

As a result, data transfer can be performed efficiently even if the performance of the host computers differs.

[Problems to be solved by the invention] However, despite the benefits obtained by adopting a standard interface and making the file device intelligent, there is a new problem in that the overhead caused by differences in data exchange protocols during access causes performance degradation. is occurring.

Among these, a particular problem is the timing of the re-association interrupt request that the file device makes to the Honneto device to start data transfer after separation due to completion of access by the file device.

Incidentally, an intelligent file device is equipped with two data buffers in order to increase the throughput of normal data transfer. As this buffer, a sector pulse that stores data in units of sectors or a track buffer that stores data in units of tracks is used.

By providing such a buffer, for example, in the case of write access, after storing the transfer data from the host device in buffer A, writing to the disk starts, and while buffer A is loading the disk, other buffer B Transfer data from the host device can be stored in the host device, and even if the disk writing speed is slow, data transfer can be performed according to the transfer speed of the host device, thereby increasing throughput.

However, when a buffer is used for data transfer, overhead occurs in either read-related data transfer or write-related data transfer, as shown in FIG.

Figure 7(a) shows the write system data transfer, and Figure 7(b) shows the write system data transfer.
) shows the data transfer of the read system, and both show the case where the timing is set so that the recombination interrupt request is raised three sectors before the target sector.

In other words, in the write system of FIG. 7(a), if a recombination interrupt request is issued to the host device at the timing of a sector pulse three sectors before the target sector, the recombination interrupt request is issued after the message input from the host device is completed. Transfer of write data from the host device to buffer A starts at time tn.

On the other hand, in the read system shown in Figure 7(b), if a combined interrupt request is issued again to the host device at the timing of the sector pulse three sectors before the target sector, a message is input after the same time. When the read data is completed and reaches the target sector, the read data is transferred to buffer A, and data transfer to the host device is started at time tn-1 when the transfer is completed.

As a result, the read system is smaller than the write system tn-1)-
An overhead of (tn>) is generated, and during this time, the acquired bus channel with the higher-level device is not used, resulting in wasted occupied time and adversely affecting performance.

The present invention has been made in view of these conventional problems, and provides an interrupt method for a file device that improves bus channel utilization efficiency by eliminating the overhead that occurs in either the read system or the write system. The purpose is to provide

[Means for solving problems] FIG. 1 is a diagram explaining the principle of the present invention.

In FIG. 1, a file device 16 equipped with a storage means such as a disk mechanism (18) is an intelligent interface that receives access requests (read access or write access) from a host device 10 and performs access control using a microprogram. (14) is provided.

The interrupt timing setting unit 16 sets the timing of the recombination interrupt request issued to the host device 10 so that the start timing of read-related and write-related data transfers is the same.

Specifically, in the interrupt timing setting unit 16, the purpose is to obtain the addition result d of the sector number a indicating the sector position at which the recombination interrupt request is made before the target sector and the value indicating the current sector position counted from the sector pulse. It is compared with the number of sectors C, and when the two match, a combined interrupt request is raised again.

[Operation When the file device receives a read or write access request from the host device, the intelligent interface uses a microprogram to control access to the corresponding disk mechanism, and when the access is completed, performs a release process to release the bus with the host device.] . At this time, in the interrupt timing setting section, the timing of the combined interrupt request is set again so that the start timing of read-related and write-related data transfers is the same (the time from the rise of the interrupt request to the start of data transfer is the same). Ru.

After the separation, a connection interrupt request is issued again to the host device at the timing set based on the sector pulse of the disk mechanism, and the connection interrupt request is issued again to the host device after the same amount of time has elapsed since the start of the engagement interrupt request in both read and write systems. Data transfer between the device and the device is started, and it is possible to prevent overhead from occurring in either the read system or the write system, and improve the efficiency of bus channel usage.

[Example] FIG. 2 is an explanatory diagram showing an embodiment of the present invention.

In FIG. 2, the intelligent interface provided in the file device 12 includes a ROM 22 that stores an MPU microprogram that controls the file device 12 according to the microprogram, a RAM 24 that the microprogram uses for data tables, and a disk drive 32. device controller 26, disk drive 32 and interface controller 30
It is composed of a data transfer controller 28 that controls data transfer between the host computer and the data buffer 34 that stores the data transferred between the data transfer controller 28 and the interface controller 30. The interface controller 30 controls the interface with the host computer. It becomes like this.

Further, for the MPU 20, a ROM 22, a RAM 24, a device controller 26, a data transfer controller 28, and an interface controller 30 are connected to a data bus 5.
0 and an address bus 52, and is controlled by the MPLJ 20 according to a microprogram.

Furthermore, the device controller 26 and the disk drive 3
2 is connected by a control signal line 54, and the disk drive 32
is connected to the data transfer controller 28 by a data signal line 56, and the data signal line 56 normally transfers serial data. Furthermore, data signal lines 58 .
Since the data transfer controller 28 normally performs serial-to-parallel conversion, the data transmitted on the data signal lines 58 and 60 becomes parallel data.

Furthermore, an interface bus 62 connects the interface controller and the host computer.

In such a configuration of the file device 12, the device controller 26 in this embodiment is provided with hardware for raising a recombination interrupt request after the release process with the host computer.

FIG. 3 is a hardware configuration diagram for setting the timing of a recombination interrupt request provided in the device controller 26 of FIG. 2.

In FIG. 3, 36 is a second register, in which an appropriate number of sectors a indicating the sector position where a recombination interrupt request is made before the target sector is stored by the execution of the microinstruction by the MPU 20 shown in FIG. . For example, taking the write system and read system shown in FIG. For the system, the number of sectors a = 3 is stored in order to raise a recombination interrupt request in synchronization with the sector pulse of three sectors before the target sector, while for the read system, it is synchronized with the sector pulse of one sector before the target sector. In order to raise a recombination interrupt request, the number of sectors a='l is stored.

38 is a counter that counts the number of sectors indicating the current sector position, and is reset by the index pulse IP obtained from the disk drive 32 and counted up by the sector pulse SP, thereby counting the number of sectors indicating the current sector position. Output.

40 is a second storage area for storing the number of sectors C indicating the target sector position.
This is a register, and when an access request is received from the host computer, the number of sectors C indicating the target sector position is stored by executing the microprogram by the MPJJ 20 of FIG.

The sector number a of the second register 36 and the sector number S indicating the current sector position counted by the counter 38 are given to an adder 42, which outputs an added value such that (a+b)=d. Addition output d of adder 42 and second register 40
The number of sectors C indicating the target sector position is input to the comparator 44, and the comparator 44 outputs an interrupt request output e that raises a recombination interrupt request when the target sector number C and the addition value d match.
is sent to the MPU 2 as an interrupt signal @q via the OR gate 46.
It is outputting to 0. Note that the OR gate 46 converts the other interrupt request signal f in the device controller 26 into MPL.
It also has a function of outputting to I20.

Next, access control of the file device will be explained with reference to the operational flow diagram of FIG.

In FIG. 4, first, in step S1, it is determined whether or not there is an access request from the host computer. When an access request is received, the process advances to step S2 to request the host computer to send a command, and in step S3, the command from the host computer is sent. Accept the request.

Subsequently, in step S4, it is determined whether or not it is a read-related command request. If it is a read-related command, the process proceeds to step S5, and a recombination interrupt timing for read-related data transfer is set.

For example, taking the read system shown in FIG. 7(b) as an example, the MPU 20 of the file device 12 shown in FIG.
The number of sectors a=1 for raising a recombination interrupt request one sector before the target sector is stored in .

On the other hand, if it is determined in step S4 that it is not a read-related command, the process proceeds to step S6 to determine whether or not it is a write-related command request, and if it is a write-related command request, the process proceeds to step S7 to set recombination interrupt timing for write-related data transfer. . For example, if we take the light system in Figure 7(a) as an example,
The MPU 20 of the file device 12 shown in FIG.
6, the number of sectors a=3 is stored in the first register 36 so that a recombination interrupt request is raised three sectors before the target sector.

Of course, even if steps S5 and S7 are both in the recombination interrupt timing setting process, the MPU 20 stores the number of sectors G indicating the target sector position based on the command request in the second register 40 of the device controller 26. .

In this way, the process for setting the recombination interrupt timing for the read system or the write system is completed, or if the command request is not for either the read system or the write system, the process advances to step S8 and the requested command is executed by the microprogram. do.

If this command execution is a read-type or write-type request command, the device controller 26 shown in FIG. 2 outputs a control signal to the corresponding disk drive 32 to start the disk drive 32.

When the execution of the request command is completed in step S8, the process proceeds to step S9, where a release process is performed to release the interface bus with the host computer, and the connection between the host computer and the file device is severed by this release.
The host computer can perform other processing.

When the release due to the bus release is completed in step S9, a seek operation is performed in the disk drive 32 of the file device @12, and through this seek operation, the sector pulse SP is sent from the disk drive 32 to the counter 38 in FIG.
The counter 38 outputs a sector number indicating the current sector position based on the sector pulse SP.

In step S11, it is determined whether the interrupt timing set in step S5 or S7 has come, based on the sector pulse obtained by the seek operation. The determination of this interrupt timing is performed by the hardware shown in FIG.
The comparator 44 compares the number of sectors C indicating the target sector position stored in the register 40, and when the two match, the O
It receives the interrupt request signal q obtained through the R gate 46 and determines that the interrupt timing has been reached.

When the interrupt timing is determined in step S11, the process proceeds to step 312, where the MPU 20 issues a recombination interrupt request to the host computer via the interface controller 30. Upon receiving the recombination interrupt request from the file device, the host computer returns a response message to the file device, and upon completion of input of the response message, the process proceeds to step 313, where data transfer of write data or read data is started.

When it is determined in step S14 that the data transfer has ended, the process advances to step S15, where the end of the transfer is notified and the series of access controls is ended.

By setting the recombination interrupt timing of the present invention as described above, for example, for the read system that caused overhead compared to the write system in FIG. 7, the recombination interrupt request can be made in synchronization with the sector pulse one sector before the target safeter. The recombination interrupt timing of the read system is set so that the recombination interrupt timing is set so that the read system starts up, and as a result, the read data transfer starts immediately after the message input from the host computer that received the recombination interrupt request is completed, and the write system starts up. It is possible to eliminate the read-related overhead that was occurring with respect to the above.

[Effects of the Invention] As described above, according to the present invention, in data transfer of recombination connection based on a recombination interrupt request, data transfer can be performed without causing any overhead in both read system and write system. The bus channel utilization efficiency can be further improved by -m.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of the principle of the present invention; Figure 2 is an explanatory diagram showing an embodiment of the present invention; Figure 3 is a hardware configuration diagram for setting interrupt timing; Figure 4 is a diagram of the file device of the present invention. Operation flow diagram of access control; Figure 5 is an explanatory diagram of a conventional system; Figure 6 is an explanatory diagram showing differences in data transfer processing depending on host performance; Figure 7 is an illustration of overhead due to differences in write system and read system. I'll go. In the figure, 10: Upper device 10a: Host computer 12: File device 14: Intelligent interface 16 Interrupt timing setting unit 18: Disk mechanism 20: MPtJ 22: ROM 24: RAM 26: Device controller 28: Data transfer controller 30: Interface Controller 32: disk drive 34: data buffer 36: second register 38: counter 40: second register 42: adder 44: comparator RO F461 Basuiga・1 sun and moon map 2nd figure visiting doctor f volume timing sign 2 set 76 hardware structure 1 concave 3rd figure

Claims (2)

[Claims] (1) In the file device (12) equipped with an interface (14) that performs access control using a microprogram in response to an access request from the host device (10), data transfer between the host device (10) and the host device (10) is started. An interrupt method for a file device, characterized in that an interrupt timing setting unit (16) is provided for setting the timing of a recombination interrupt request for recombination so that the start timing of read-related and write-related data transfers is the same. . (2) The interrupt timing setting unit (16) includes a first register (36) that stores an appropriate number of sectors indicating the sector position where a combined interrupt request is made again before the target sector, and a first register (36) that is reset by an index pulse. A counter (3) that counts sector pulses and outputs the current sector position.
8), a second register (40) that stores the number of target sectors, and the value of the first register (36) and the counter (38).
an adder (42) that adds the value of , and compares the addition result of the adder (42) with the number of target sectors in the second register (40), and when the two match, outputs a combined interrupt request again. 2. The interrupt system for a file device according to claim 1, further comprising: a comparator (44);