JPH05128050A - Method for data retrieval control in electronic computer system - Google Patents

Abstract

PURPOSE:To prevent a system from being reduced in its performance by using retrieval information stored in a main storage device and retrieving objective data by using a DMA transfer function and a data retrieving function provided in a disk controller. CONSTITUTION:A microprocessor 301 in the disk control device 3 receives a retrieval command from a processor 1 through a system bus A. In this case, the processor 301 reads out a retrieving character string from a main memory 2 by DMA transfer and stores the read contents in a buffer memory 304. Then the processor 301 reads out file management information stored in a resident table 201 from its leading address to a data transfer buffer 303 by means of DMA transfer. A data retrieving circuit 305 compares the read information with the retrieving character string stored in the memory 304. After ending the retrieval, the processor 301 generates a retrieval result based upon the end state stored in the circuit 305, writes the retrieval result in the end parameter area of a control parameter stored in the main memory 2 by the DMA, and reports the end.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data search control method in an electronic computer system, and more particularly to an electronic computer system in which search information (file management information) in a disk device is resident in a main memory and used. The present invention relates to a data search control method in an electronic computer system suitable for improving the processing capacity of the electronic computer system.

[0002]

2. Description of the Related Art Data in a conventional computer system
As a data retrieval control method, for example, JP-A-56-2976
As disclosed in Japanese Patent Laid-Open No. 0, the disk control device is known to perform data search in the disk device based on the information specified by the program of the host device.

[0003]

In recent years, for the purpose of improving the system performance, search information with a high access frequency in a disk device is preliminarily read in the main storage device and the search information read in the main storage device is used. The number of computer systems that do this is increasing.

In the above prior art, since the area to be searched is the storage area of the disk device, in order to search for the target file based on the search information read on the main storage device, It is necessary to perform a comparison operation of the search information in the main storage device by the program or to access the disk device again to perform the character string search, which causes a problem that the processing capacity of the entire system is lowered.

The present invention has been made in view of the above-mentioned problems of the prior art, and uses the search information read in the main storage device and has a DMA transfer function and data which the disk control device has. By searching for the target data using the search function, it is intended to prevent the system performance from deteriorating.

[0006]

A data search control method in an electronic computer system according to the present invention comprises a processing device, a main storage device, a disk control device having a DMA transfer function and a data search function, and a disk device. Was
It is applied to an electronic computer system that stores search information of a disk device in the main storage device, and the search information stored in the main storage device is transferred to the DMA of the disk control device.
A feature is that the target information is retrieved from the retrieval information retrieved by using the data retrieval function of the disc controller by taking it into the disc controller using the transfer function.

[0007]

According to the present invention, by the DMA transfer function of the disk controller, the search information stored in the main memory is taken into the disk controller and the data searching function of the disk controller is realized. The target information is retrieved from the retrieved retrieval information.

Therefore, it is not necessary to perform a comparison operation of the search information in the main storage device by the program of the processing device,
Further, since it is not necessary to access the disk device to search for a character string, it is possible to improve the processing capacity of the entire system.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail with reference to the embodiments shown in the accompanying drawings. FIG. 1 is a block diagram showing an embodiment of an electronic computer system according to the present invention.

As shown in FIG. 1, the processing device 1, the main memory 2 and the disk control device 3 are connected to each other via a system bus A. The disk control device 3 and the disk device 4 are connected via a disk interface E. As shown in the figure, the disk control device 3 includes a microprocessor 301, a system bus control circuit 302, a data transfer buffer 303, a buffer memory 304, a data search circuit 305, a start register 306, a control memory 307, It is composed of a selector 308, a disk interface circuit 309, a micro program memory 310, and a microprocessor bus B. The storage area of the magnetic disk device 4 is roughly divided into a file management information area 401 and a data area 402.

A program for operating the processing device 1 is stored in the main memory 2 although not shown. This program reads the file management information 5 stored in the file management information area 401 of the magnetic disk device 4 when the system is started up, and the read file management information 5 is the disk interface E and the disk interface control circuit 309. It is stored in the resident table 201 in the main memory 2 via the data transfer buffer 303 and the system bus A. Besides this, main memory 2
The file name of the file stored in the data area in the disk device 4 is stored in.

FIG. 2 is a diagram showing the format of the file management information 5 stored in the file management information area 401. The file management information 5 is composed of a plurality of blocks as shown in the figure, each block is composed of a plurality of records, and one record is a file name 501 and a storage start position (position of the data area of the magnetic disk device 4) 50.
2, file size 503, and other management information 504. Data area 4 in magnetic disk device 4
When accessing the file stored in No. 02, the file name 501 is used as a keyword to search the file management information 5 stored in the resident table 201 in the main memory 2, and the storage start position 502 is calculated. Therefore, the processor 1 prepares the control parameters 6 of the format shown in FIG. 3 on the main memory 2.

As shown in FIG. 3, the control parameter 6 is
It is composed of a start parameter 600 and an end parameter 610. The start parameter 600 includes a command code 601, a search data start memory address 602 indicating the start address in the main memory 2 storing the file name of the search target, and a resident table start memory address 603 which is the start address of the resident table 201. When,
Record length 604 and number of blocks to execute search 605
It consists of and. Also, the end parameter 610
Is for writing the search result and the like after the end of the search. The search result 611 indicating the presence or absence of the target file and the number of processing blocks indicating the number of blocks searched (if the target file exists, the existence of the target file exists). Corresponding to the block number) and an in-block record position 613 indicating a record position in the block when the target file exists in the block.

Next, the operation of the present invention will be described. The processor 1 uses the control parameters 6 shown in FIG.
After the above preparation, the resident table top memory address 603 of the control parameter 6 is stored in the start register 302,
Invokes the search operation.

The microprocessor 301 in the disk controller 3 receives the activation detection signal C output from the processor 1.
When the activation is received through the activation register 302 and activation is detected, the control parameter 6 on the main memory 2 is fetched into the control memory 307 by DMA transfer using the system bus control circuit 302 and the data transfer buffer 303. .. next,
When the microprocessor 301 analyzes the command code 601 stored in the control memory 307 and recognizes that it is a search instruction, the microprocessor 301 communicates with the system bus control circuit 302 and the data.
The search data start memory address 602 on the main memory 2 is accessed using the data transfer buffer 303, and the search character string indicating the target file name is stored in the buffer memory 30.
Take in 4.

Next, the microprocessor 301 uses the system bus control circuit 302, the data transfer buffer 303 and the data comparison circuit 305 to transfer the resident table 201 on the main memory 2 by DMA transfer. The file name (search character string) that has been fetched and fetched in the buffer memory 304 is compared and a search is performed. Microprocessor 3
01 controls the selector 308 to output the data input from the data transfer buffer 303 during the search processing.

The data search circuit 305 finds the target file name by the above search operation, or
When the search processing is performed for the number of blocks 604 shown in, the operation end signal D is output.

When the end of the search operation is detected by the search operation end signal D, the microprocessor 301 creates a search result from the end state held in the data search circuit 305, and the system bus control circuit 302 and data -Using the data transfer buffer 303, the end parameter on the main memory 2
The search result 611 of the data 610, the number of processed blocks 612, and the in-block record position 613 are written by DMA transfer. After that, the microprocessor 301 reports the end to the program of the processing device 1.

When the program of the processing unit 1 detects the end report from the disk control unit 3, the end parameter 61 is sent.
The storage position of the file in the data area 402 of the disk device 4 is calculated from the search result 611 of 0, the number of processed blocks 612, and the in-block record position 613, and the target file is accessed.

Selector 308 in the disk controller 3
Selects one of the input data to the data search circuit 305 as read data from the main memory 2 or read data from the magnetic disk device 4. Yes, and controlled by the microprocessor 301. This is because all the file management information 5 stored in the file management information area 401 in the magnetic disk device 4 is stored in the main memory 2 as a resident table in the main memory 2 due to system configuration restrictions or the like.
If the target file cannot be found as a result of performing the search operation on the resident table 201, the remaining file management information 5 stored in the magnetic disk device 4 cannot be stored. This is because it is possible to calculate the storage location of the file by performing a search operation for.

As is apparent from the above description, according to the above-described embodiment, the processing device 1 reads, for example, the file management information 5 which is frequently accessed on the system from the disk device 4 and stores it in the resident table 201 of the main memory 2. Store it. The file management information 5 stored in the main memory 2
When a character string (file name) is searched for, the processing device 1 causes the main memory start address where the search target character string is stored, the number of search characters, the main memory start address where the table is stored, The disk controller 3 is instructed of the format information on the main memory 2 and the search operation is started.

The disk controller 3 reads a search character string for searching from the search data main memory start address 602 designated by the program into the buffer memory 304 in the disk controller by DMA transfer, and further stores it in the main memory 2. While reading the file management information 5 by DMA transfer, the contents of the buffer memory 304 are compared, and the result is reported to the processing device 1.

The processing device 1 calculates the storage position of the character string based on the search result reported from the disk control device. As a result, the character string search using the file management information read on the main memory 2 is performed by the D of the disk controller.
This can be performed using the MA transfer function and the data search function, and the program can execute other processing during the character string search, so that it is possible to prevent the system performance from deteriorating.

[0024]

According to the present invention, the data search operation for the information in the main memory is performed by the DMA separately from the program.
Since the transfer function can be used, in a system in which the information in the disk device is resident in the main memory, it is possible to prevent a reduction in the processing capacity of the entire system due to the data search operation.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of an embodiment of a computer system using the present invention.

2 is an explanatory diagram showing a format of file management information stored in a file management information area of the disk device shown in FIG. 1. FIG.

FIG. 3 is a control parameter stored in a main memory shown in FIG.
FIG. 4 is an explanatory view showing an example of a data format.

[Explanation of symbols]

1 ... Processor, 2 ... Main memory, 3 ... Disk controller,
4 ... Disk device, 5 ... File management information, 6 ... Control parameter, 201 ... Resident table, 301 ... Microprocessor, 302 ... System bus control circuit, 303 ... Data transfer buffer, 304 ... Buffer memory, 305 ...
Data search circuit, 306 ... Startup register, 307 ... Control memory, 308 ... Selector, 309 ... Disk interface control circuit, 310 ... Micro program memory, 501 ... File name, 502 ... Storage start position,
503 ... File size, 504 ... Other management information, 6
00 ... Startup parameter, 601 ... Command code, 60
2 ... Search data top memory address, 603 ... Resident data
Bull head memory address, 604 ... Record length, 605
... Block number, 610 ... End parameter, 611 ... Search result, 612 ... Processing block number, 613 ... Record position in block, A ... System bus, B ... Microprocessor bus, C ... Start detection signal, D ... Search operation End signal, E ... Disk interface,

Claims (1)

[Claims] 1. A processing device, a main storage device, and a disk control device having a DMA transfer function and a data search function,
In a computer system configured by a disk device and storing search information of the disk device in the main storage device, the search information stored in the main storage device is controlled by using the DMA transfer function of the disk control device. A data retrieval control method in an electronic computer system, characterized by retrieving target data from retrieval information captured in a disc and using a data retrieval function of a disk controller.