JPS60243761A - Method for controlling reception of data from external storage device - Google Patents

Abstract

PURPOSE:To read out efficiently large volume of data on the transmission side by counting up a number corresponding to the number of data received by work stations to control the received data. CONSTITUTION:A station controller 1 reads/writes data from/in files of an external storage device 5 in accordance with the requests of the work stations WS1-WSn and transmits/receives data to/from a host device. Each work station WS is provided with a control part 10, an IPL loader 11 for executing IPL, a counter 12 for counting up the number of blocks of received data, a memory 13 for storing a received program or the like, and an AND circuit 14 and the received data are controlled by the counted value of the counter 12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device that efficiently responds to the requests of a plurality of users and simultaneously supplies the same information stored in an external storage device.

[Conventional technology]

For example, IPL (Initi
When multiple workstations (users) are used for the same file, such as when
When data was read almost simultaneously from two workstations, the data was sent to each workstation at a time.

That is, as shown in FIG. 4, the information stored in the external storage device EXTM is generally managed in units called files FIL, and this file can be accessed in units of blocks and records.The read exit of this file FIL is as follows.
It is believed that reading the file from the beginning to the end in one go in ascending order of blocks (or records) takes the least amount of time. In this method, requests from a plurality of users are processed sequentially for each user, and users making simultaneous requests are always forced to wait for their turn to be processed. For example, if it takes t hours to read one file, it takes txn hours to read files up to the n-th user, which is a disadvantage in that it takes a very long time. In the case of FIG. 2, when there are simultaneous read requests for file A from workstations WS1 to WS3, the station controller SC
reads file A for each request and converts it to 3
I had to send it out again.

[Problem that the invention seeks to solve]

The present invention solves the problem of having to read and send the file for each user when multiple users request to read the same file almost simultaneously.

[Means for solving problems]

In order to solve the above problems, the external storage device data reception control method of the present invention includes a controller that reads and sends data stored in the external storage device, and a plurality of works that receive data sent from this controller. In the multi-workstation system having stations, the workstation is provided with a data length counter that counts a number corresponding to the number of received data, and the received data is controlled by the data length counter.

[Effect]

Accordingly, in the present invention, data is read from a file in an external storage device in ascending order and sent to each workstation multiple times. Each workstation counts the length of captured data. Now, as shown in FIG. 2(a), the workstation WSI receives the first block 1 of the file in order, and the workstation WS
2 receives from block 3, and workstation WS3
is received from block 6, and so on, the reception start position fZ
The difference is that even if workstation WSI receives all up to block n and its counter indicates that the total number of data has been received, the counters of workstations WS2 and WS3 do not indicate that the total number of data has been received. Since there is no data, the station controller sends the data of file A from block 1 again. As a result, as shown in FIG. 2(b), when the workstation ws1 receives the unreceived data 1.2, the counter indicates that the total number of data has been received, so it does not take in any subsequent data. Workstation WS3 has unreceived data blocks 1 to 5.
When it receives, the counter will display that the total number of data has been received, so no further data will be taken in. Therefore,
The same data can be sent to multiple workstations without having to send the data as many times as the number of workstations that have requested data reception, as in the conventional case.

〔Example〕

An embodiment of the present invention will be described based on FIGS. 1 to 3.

FIG. 1 is a configuration diagram of an embodiment of the present invention, FIG. 2 is an explanatory diagram of the data transmission and reception state, and FIG. 3 is an explanatory diagram of the transmission data format.

In the figure, 1 is a station controller, 2 is an input/output control unit, 3 is a request/file identification unit, 4 is a file succession unit, 5 is an external storage device, 1o is a control unit, and 11 is an IP
12 is a counter, 13 is a memory, 14 is an AND circuit, and WSI-WS3- is a workstation.

Station controller 1 is Works Chee Shore W
External storage device 5 according to the request of S1-WS3-
read or write data to files,
It transmits and receives data to and from a host device (not shown), including the input/output control unit 2 and the workstations WS1 to W.
It is provided with a request/file identification section 3 for identifying a file for which a read request has been made from S3-, and a file succession section 4 for reading data from the external storage device 5.

The workstation WSI is, for example, a Pos terminal and has an intelligence function, and includes a control unit 10. IPL loader 1 that performs TPL loading
1. A counter 12 that counts the number of blocks of received data, a memory 13 that stores received programs, etc.
Equipped with 44 AND circuits. When the number of blocks of the program to be received at the time of IPL is n, the final count value of the counter 12 is initialized to n. Then, it is incremented by one every time l blocks are received, and a carry is output when n is counted. Therefore, even if file A is received from block 6 instead of from block 1 in FIG. 2(a), from block 6 to block n
Even if the counter 12 receives up to (n-6+1), it does not output a carry. When this file A is sent again from block 1, the counter 12
outputs a carry. Then, data of file A will not be imported any more.

Workstations WS2 and WS3- are also configured similarly to WSI.

In addition, at least one of the workstations WSI to WS3
When the station controller 1 is instructed to transfer IPL data, the station controller 1 sends out transmission data in the format shown in FIG. 4 from the input/output control section 2. At the beginning of this transmitted data, FF (hexadecimal) indicating that it can be captured by any workstation is written, and at the next header part H, a control signal is written, and the number of blocks of received data is written. (20 in case of file A) MA
Xll&l, segment number 5EGNII divided into units of 64, l+ for block number SE of transmission data,
(within the segment number), file name A, actual data DATA, etc. are entered. The workstation that sent the request looks at the file name of the data sent in this format, and if it is the file name of the request destination, it recognizes the number of blocks for that file from the MAX positive and sets its own counter 12. This MA
It will be set to X-block.

Next, the operation of the present invention will be explained.

(11 In Fig. 1, workstations WS1 to W
An IPL request to transmit file A is sent to station controller 1 from S3. At this time, as shown in FIG. 2, it is assumed that the IPL request of workstation WS1 is made first, followed by IPL requests of WS2 and WS3 in that order.

(2) When the station controller 1 receives the request from the workstation WS1 at the input/output control section 2, it transmits this to the request file identification section 3 to detect the file name of the request destination.

When the request file identification unit 3 recognizes that this is file A, it calculates the number of blocks and sends it to the input/output control unit 2, and causes the file succession unit 4 to read the requested file A. .

At this time, the file succession unit 4 stores file A in block 1.
2... and read in ascending order.

(3) The input/output control unit 2 determines the total number of blocks (MAXl) of the file A transmitted from the request/file identification unit 3.
lm) , based on the file name A, the segment number SEG11b sent from the file succession unit 4, the block number 5EQ11h, the data DATA of that block, etc., insert FF at the beginning part and a control signal in part H of the header. , creates transmission data in the form shown in FIG. 3, and sends it to the workstations wsi and WS2-. Based on this data, the IPL loader 11 in the workstation WSl initializes the counter 1z to n, which is the total number of blocks to the file (MAXNa), and turns on the AND circuit 14. First, data of block number 1 is stored in the memory 13. Then, the IPL loader 11 increments the counter 12 by 1. Next, the file successive section 4 reads block 2 of the file A. When this block 2 is sent out, the input/output control unit 2 changes the format shown in FIG. 3 to block number 2 and sends it out.

When the workstation WSI receives this data, the counter 12 is further incremented by 1 and counts to 2. In this way, the data of file A is sequentially stored in the memory 13 of workstation WSI.

(4) When the data of file A is being read out sequentially in this way, when an IPL request for file A is output from workstation WS2, workstation WS2 outputs the file that station controller l is currently sending. Data from A can be imported. Therefore, as shown in FIG. 2(a), data is imported from block 3 to the file. The counter of the workstation WS2 is initially initialized to n, but when the block 3.4. Similarly, workstation WS3
Also, as shown in FIG. 2 (Ca), the data of file A is stored starting from block 6.

(5) In this way, the data of file A is sent out sequentially and the last block n is sent out, and when this is stored in the workstation WSI, its counter 12 counts the initial setting value n, so it outputs a carry, As a result, the IPL loader does not import the data of file A. In addition, the control unit 10 also controls the T of file A.
Drop PL request. Therefore, station controller 1 recognizes that the IPL request for file A from workstation WSI has been dropped. However, since there are IPL requests for file A from workstations WS2 and WS3, file successive section 4 sequentially reads file A from block 1 again, and input/output control section 2 sends them out in the same manner.

(6) When block 2 is received by workstation WS2, the counter of workstation WS2 generates a carry, so its control unit
Drop PL request. When block 5 is received by workstation WS3, the counter of workstation WS3 generates a carry, so its control section drops the IPL request for file A. If all the IPL requests for file A are dropped in this way, the request/file identification unit 3 of the stage control controller 1 controls the file succession unit 4 to stop reading the file A, so that the file A data Sending is stopped when all of the data are stored in the workstations WSI to WS3.

If there is a read request for another file B from another workstation, the station controller 1 will now control the transmission of this file B.

〔Effect of the invention〕

In the present invention, when there are read requests for the same file from multiple workstations, the requests are read out sequentially and sent out with information + supply order added so that the multiple workstations can receive them simultaneously. The station can be configured to count the amount of data and stop receiving any more data when the required amount of data has been received, so the sending side does not have to read large amounts of data efficiently and send out data for each user. Since there is no transmission time, the transmission time can be significantly shortened. Moreover, the IPL time of O3 of the workstation can always be completed within a fixed time.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram of an embodiment of the present invention, Fig. 2 is an explanatory diagram of the data transmission and reception state, Fig. 3 is an explanatory diagram of the transmission data format, and Fig. 4 is a conventional external storage device data reception control system. It is an explanatory diagram. In the figure, 1 is a station controller, 2 is an input/output control unit, 3 is a request/file identification unit, 4 is a file succession unit, 5 is an external storage device, 10 is a control unit, and 11 is an IP
12 is a counter, 13 is a memory, 14 is an AND circuit, and WSI, WS2, and WS3 are work stations. Patent applicant Fujitsu Ltd. Agent Patent attorney Akira Yamatani Sakae Ivar w, +l WSJ Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] In a multi-workstation system that has a controller that reads and sends data stored in an external storage device and multiple workstations that receive data sent from this controller, the number corresponds to the number of data received by the workstation. 1. A data reception control method for external storage device, characterized in that a data length counter is provided to count the data length, and received data is controlled by the data length counter.