JPH03201122A - Data updating system for auxiliary storage device - Google Patents

Abstract

PURPOSE:To reduce the overhead of I/O by executing partial writing in a block of an auxiliary storage device by a single data updating channel program without dividing the operation 2<= I/O operations. CONSTITUTION:An I/O executing means 5 inputs the data updating channel program formed by a channel program forming means 4, outputs buffer information, accesses an operating system 7, and executes the program to update data. After ending said processing, the system 7 starts a buffer memory releasing means 6, which inputs the buffer memory information outputted from the means 5, accesses the system 7 and sends an address and a size to be memory information. The system 7 releases a buffer memory 102 allocated to a main storage device 10. Consequently, the overhead of I/O can be removed and the increment of cost of hardware can be suppressed.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention provides storage in an auxiliary storage device in which the unit of writing is fixed to a certain size and the storage area is made up of a plurality of units of writing. The present invention relates to a data update method for an auxiliary storage device that updates data that is currently being stored.

(Prior Art) In a directly accessible auxiliary storage device such as a magnetic disk device, a storage area is divided into a plurality of blocks that can be addressed by a program.

If the auxiliary storage device is composed of only the same devices, it is desirable that this block be large in order to increase the storage density, and it is desirable that it be a certain size in order to facilitate the control of the control device. , data is written to the auxiliary storage device in block units, and when software updates data stored in the storage device, the block in the storage area of the auxiliary storage device and the storage area where the data is updated are A mismatch may occur.

Therefore, the conventional data update method for auxiliary storage devices is to first move all blocks in the area where data is to be updated to the main storage device, update the data on the main storage device, and then transfer it to the main storage device. All blocks were returned to auxiliary storage.

C-Problem to be Solved by the Invention H) However, in the conventional data update method of the auxiliary storage device described above, it is necessary to first read out the entire block, update the required part, and write it back again. If this was done in software, the input/output would be performed twice, increasing overhead, and if done in hardware, the hardware cost would increase.

(Means for Solving the Problems) A data update method for an auxiliary storage device of the present invention updates the contents of data stored in an auxiliary storage device whose storage area is composed of a plurality of blocks of a certain size. A method for updating data in an auxiliary storage device comprising a channel program input means for inputting a channel program included in an application program, and analyzing the channel program input by the channel program input means to match the data update position in a storage area. channel program analysis means for calculating the size of a buffer memory for saving unupdated data of blocks whose data is only updated; and a buffer memory for allocating the buffer memory of the size calculated by the channel program analysis means to the main storage device. allocation means; channel program generation means for generating a data update channel program from the data update position information calculated by the channel program analysis means and the buffer memory address of the buffer memory allocated to the main storage device by the buffer memory allocation means; An input/output execution means for executing data update based on the data update channel program generated by the channel program generation means; and a buffer memory release means for releasing the buffer memory allocated to the main storage device by the buffer memory allocation means. be done.

(Example) Next, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a schematic block diagram showing an embodiment of the data update method of the auxiliary storage device of the present invention, and this embodiment has a channel program input terminal p1t that inputs a channel program 81 included in the application program 8; Analyze the channel program 81 input by the channel program input means 1 to determine the data update position in the storage area of the magnetic disk device 11 and the size of the buffer memory that will cause the unupdated data of the block whose data is only partially updated to be 'iAM'. A channel program analysis means 2 for calculating, a buffer memory allocation means 3 for allocating a buffer memory of the size calculated by the channel program analysis means F12 to the main storage device 10, and a buffer and data update position information calculated by the channel program analysis means 2. A channel program generation means 4 generates a data update channel program from the buffer memory address of the buffer memory allocated to the main storage device 10 by the memory allocation means 3, and a data update channel 10 generated by the channel program generation means Fi4.
:" It is composed of an input/output execution means 5 for executing the duram and a buffer memory release stage 6 for releasing the buffer memory allocated to the main storage device 10 by the buffer memory allocation means 3. FIG. Program input means 1
3 is a flowchart showing the processing of the channel program analysis means 2, 16th is a flowchart showing the processing of the buffer memory allocation means 3, and FIG. 5 is a flowchart showing the processing of the channel program generation means 4. 6 is a flowchart showing the processing of the input/output execution means 5, FIG. 7 is a flowchart showing the processing of the buffer memory release means 6, and FIG. 8 is a flowchart showing the processing of the input/output execution means 5. FIG. 9 is a diagram illustrating an access area, and FIG. 9 is a diagram illustrating a data update channel program. The operation of this embodiment will be explained below.

In FIG. 1, an example will be explained in which the application program 8 writes data to a certain area 111 on the magnetic disk device 11, which is an auxiliary storage device. The area 111 is the eighth
This is shown as an area from address SL to 82 in the figure and FIG. The storage area of the magnetic disk device 11 is divided into blocks of fixed length P bytes, and data is written in blocks. The area 111 that the application program 8 attempts to write to is L bytes from byte address S1 in the magnetic disk device ll, and the area 111
The data written to is L byte update data 101.

First, when the application program 8 calls the operating system 7 for data input/output, the operating system 7 starts the channel program input means 1.

The channel program input means 1 reads out the channel program 81 included in the application program 8.Step 1
1) Start up the channel program analysis means 2 (step 12).

The channel program analyzer a2 determines whether or not the data input/output is a write (step 21). If it is not a write, there is no writing to the block due to data update, so the channel program 81 of the application program 8 is executed by the operating system. 7 (step 22)
, When data input/output is writing, there is a possibility that partial writing to a block due to data update will occur, so the magnetic disk device 11 provided in advance from the outside.
The value of the write unit, that is, the number of bytes P of a block, is input (step 23).

Next, it is determined whether the access start position SL coincides with a block boundary (step 24). This determination is performed as follows. Referring to FIG. 9, the access start byte address SL is S+ = PXN + Dt ・” (1) However, since N is the integer part of 81 /P, if = 0, then S is of the Nth block. Since it matches the start address, it matches a block boundary, and if DI = O, S starts from the D1 byte in the Nth block, so it does not match a block boundary.The access start position S, If it does not match the block boundary, the access start position information for accessing the DI area in FIG. 1 (1=P
...(2) Byte length = D, ...(3
) Next, it is determined whether the access end position S2 coincides with a block boundary (step 24). This determination is performed as follows. Referring to FIG. 9, the byte address S1 at which the access ends is Ss = S r + L = (N0M) X P
D2... (4) Therefore, Dt = (N+M)xP-(S+1)...(5)
However, since M = (DI 10L)/integer part of P - (6), if D2 = 0, S2 matches the start address of the N10M block, so it matches the block boundary. Therefore, if D2=O, Sl ends at the (PDz)th byte in the N10Mth block, so it does not match the block boundary. If the access end position St does not coincide with the block boundary, access end position information for accessing the DI area in FIG. 9 is generated (step 27), and this access end position information is (4
) and (5), the access end byte address S 2 = S I 0 L (7> Byte length = Dt ... 0 obtained as (8)) Next, determine whether there is a partial write due to data update. (Step 28), DI.

Since partial writing does not occur only when both DIs are zero, the operating system 7 is requested to execute the channel program 81 (step 22).

If DI and Dt are both zero, output S..., DI82 and DI as partial write information.Step 29
), the buffer memory allocation means 3 inputs Dr and Dx outputted from the channel program analysis means 2 as the buffer memory size (step 31), calls the operating system 7, and assigns the buffer memory 102 of D t + D 2 bytes as the main buffer memory size. Assign to memory device ff1o (
Step 32〉0 Next, output the address X of the buffer memory 102 allocated to the main storage device 10.Step 33
), the channel program generation means 4 is activated (step 34).

The channel program generation means 4 first determines whether the access start position is a partial write (step 41).
), if DI is not zero, the access start position will be a partial write, so channel control Bct, C snow accesses DI in FIG.

Generate a starting block channel program consisting of Cs and C. , the seek address is S, ., the data length is DI, and the buffer memory address of the buffer memory 102 of the main storage device 10 is X.

Channel I11# word CI, C* is used to save an area in which data is not updated to the buffer memory 102 allocated to the main memory 10, and channel control words cs, C6 are saved from the buffer memory. Area 1 is used to write back to area D1 on the magnetic disk.Next, area 1 is used to write update data 101 by application program 8.
An intermediate block channel program consisting of a data control word C7 that accesses the area 11 is generated (step 43). Since this data control word C7 is accessed following the area 11, the channel program of the channel 10-gram 81 shown in FIG. 0 order generated by rewriting the command of control word 2 into a chain; Determine whether the access end position is a partial write (step 44); if DI is not zero, the access end position is a partial write. Therefore, the DI in Figure 9
A finished block channel program consisting of channel control words Cs, C4 and data control word Cm is generated (step 45), which accesses channel control words Cs, C4 and data control word C (step 45).

is the area Dl of the access start block boundary M! This is the channel control word or data control word to be accessed, the seek address is S2, the data length is DI, and the buffer address of buffer memory 02 is X0DI. The channel control words Cs and C4 are used to save an area of the size of DI in which data will not be updated to the buffer memory 02 allocated to the main storage device 10, and the data control word Cs is used to save the data in the area of the size of DI to the buffer memory 02 allocated to the main storage device 10, and the data control word Cs is transferred from the buffer memory back to the D1 area on the magnetic disk. Next, the input/output execution means 5 is activated (step 47).

The input/output execution means 5 is a channel program generator p14.
Input the data update channel program outputted by Step 51), output the buffer memory information consisting of the address and size of the buffer memory 02 of the main storage device 10 that is in use in Step 52), call the operating system 7 and update the data. The channel program is executed to update data (step 53).

When the data update channel program activated by the input/output execution means 5 ends, the operating system 7 activates the buffer memory release means 6.

The buffer memory release means 6 inputs the buffer memory information outputted by the input/output execution means 5 (step 61), calls the operating system 7, and sends the address X and size D++Dz, which are buffer memory information, to the operating system 7.

Then, the operating system 7 uses the main memory, 1
Free the buffer memory 102 allocated to 0.

(Effects of the Invention) As explained above, according to the present invention, partial writing to a part of a block of an axial storage device in which the storage area is composed of a plurality of blocks with write units of fixed length can be performed twice or more. Since it can be achieved with a single data update channel program without dividing it into outputs, input/output overhead can be eliminated and increases in hardware costs can be avoided.
The present invention has the above effects.

[Brief explanation of drawings]

FIG. 1 is a schematic block diagram showing one embodiment of the present invention, and FIG.
FIG. 3 is a flowchart showing the processing of the channel program input child p11, FIG. 3 is a flowchart showing the processing of the channel program analysis means 2, FIG. 4 is a flowchart showing the processing of the buffer memory allocation means 3, and FIG. 5 is a flowchart showing the processing of the channel program analysis means 3. Means 4
6 is a flowchart showing the processing of the input/output execution means 5, FIG. 7 is a flowchart showing the processing of the buffer memory release means 6, and FIG. 8 explains the access area by the application program 1. FIG. 9 is a diagram illustrating a partial write channel program. DESCRIPTION OF SYMBOLS 1... Channel program input means, 2... Channel program analysis means, 3... Buffer memory allocation means, 4... Channel program generation means, 5...
Input/output execution means, 6...buffer memory release means, 7
. . . Operating system, 8. Application program, 9.-cpu, 10. Main storage device, 11.
...Magnetic disk, 81...Channel program,
101... Update data, 102... Buffer memory, 111... Area.

Claims (1)

[Scope of Claim] In a data update method for an auxiliary storage device that updates the contents of data stored in an auxiliary storage device whose storage area is composed of a plurality of blocks of a certain size, the method is included in an application program. A channel program input means for inputting a channel program, and a buffer memory for analyzing the channel program inputted by the channel program input means and saving the data update position in the storage area and the unupdated data of the block whose data is only partially updated. channel program analysis means for calculating the size of the channel program analysis means; buffer memory allocation means for allocating the buffer memory of the size calculated by the channel program analysis means to the main storage device; and data update position information calculated by the channel program analysis means. Channel program generation means for generating a data update channel program from the buffer memory address of the buffer memory allocated to the main storage device by the buffer memory allocation means; A data update method for an auxiliary storage device, comprising: an input/output execution unit for executing the input/output execution unit; and a buffer memory release unit for releasing the buffer memory allocated to the main storage device by the buffer memory allocation unit.