JPH02211562A - Information processing system - Google Patents

Abstract

PURPOSE:To easily detect unjust memory breakdown by dividing a memory at a constant size, allocating allocation objective block every other part, and checking whether or not information is written outside the objective block at the time of returning the block. CONSTITUTION:In a system in which plural terminals dividedly use a page to be a memory allocation unit, when the terminal requires the memory during the execution of a program 1, it accesses a block allocating means 2. The means 2 checks whether or not the allocation objective block exists in a memory 6, when it does not exist, an initializing means 3 is accessed to secure the new memory, and then an allocating processing is executed. When the block is unnecessary, the terminal accesses a block returning means 4, the means 4 makes a memory breakdown checking means 5 check the presence/absence of the memory breakdown of the block other than the objective block, then the means 4 returns the block, and reports a result to the terminal. Thus the unjust memory breakdown is checked, and the adverse effect between the terminal can be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention is used for memory management in information processing. The present invention relates to a memory corruption detection method that can easily detect memory corruption when returning the memory.

〔overview〕

In a method of extracting information held in memory, making corrections, and returning it to that memory, allocation target blocks are placed every other block, and upon return, it is checked whether blocks that are not allocated have been changed. By checking this, it is possible to check for illegal memory destruction.

[Conventional technology]

The conventional system has an information processing device 1 as shown in FIG.
2 takes out information held in the memory 6 according to instructions from the work terminal 11, changes and corrects the information, and returns the corrected information to the memory 6. In other words, a page, which is a unit of hardware memory allocation, is divided and used by multiple jobs.

[Problem that the invention seeks to solve]

In systems such as this, where pages, which are the unit of memory allocation in hardware, are divided and used by multiple pieces of information, a bug in one job can destroy the memory used by other jobs. This has the disadvantage that it takes a lot of time to investigate the cause, since the effect is not limited to the job itself but affects other jobs, and the effect appears as a different phenomenon each time.

The present invention aims to eliminate such drawbacks and provides a method that can easily detect memory corruption.

[Means for solving problems]

The present invention provides an information processing system that includes means for retrieving information held in a memory according to a specification from a work terminal, and means for modifying the information and returning the modified information to the memory. When returning the information to the memory, block allocation means allocates blocks according to the chain of blocks to be allocated, and a block allocation means that divides a page, which is an allocation unit of 7%-ware, into blocks of a certain size, and divides every other divided block into blocks. an initial setting means for chaining blocks to be allocated in order to allocate them to a block, a block return means to incorporate blocks to be returned into the chain of blocks to be allocated at the time of return, and a block to be returned that does not exceed the size of the block to be returned at the time of return. The present invention is characterized by comprising a memory corruption check means for checking whether or not.

[Effect]

When returning memory, it checks whether the memory has been written to in excess of the allocated memory size, allocates blocks according to the chain of blocks to be allocated, and divides pages, which are the unit of hardware allocation, into blocks of a certain size. Split the blocks and chain the blocks to be allocated in order to allocate every other divided block. When returning a block, the block to be returned is included in the chain of blocks to be allocated, and it is checked whether writing has been performed exceeding the size of the block to be returned.

This makes it possible to check whether the memory has been improperly destroyed.

〔Example〕

Next, embodiments of the present invention will be described based on the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, and FIG. 7 is a block diagram showing the configuration of a system according to the embodiment of the present invention.

As shown in FIG. 7, the embodiment of the present invention is an information process that retrieves information held in the memory 6 according to a specification from the terminal 11, changes and corrects the information, and returns the corrected information to the memory 6. The present invention is further characterized by block allocation means 2 which allocates blocks according to the chain of blocks to be allocated when returning information to the memory, and which divides pages, which are hardware allocation units, into blocks of a fixed size. an initial setting means 3 for chaining blocks to be allocated in order to divide and allocate every other divided block; a block return means 4 for incorporating blocks to be returned into a chain of blocks to be allocated at the time of block return; A memory destruction check means 5 is provided for checking whether writing has been performed exceeding the size of the block to be returned.

FIG. 2 is a flowchart showing the processing flow of the block allocation means according to the embodiment of the present invention. The block allocation means 2 performs a free block search to check whether or not the block to be allocated exists in the chain of the block to be allocated, and when there is no free block, calls the initial setting means 3 to check the chain of the block to be allocated. Allocate the first block.

FIG. 3 is a flowchart showing the processing flow of the initial setting means according to the embodiment of the present invention. Initial setting means 3 allocates new memory, divides the allocated memory into a certain size, creates a chain of allocated blocks that connects every other block with a chain, and identifies blocks that are not incorporated into the chain. Initialize with the pattern.

FIG. 4 is a flowchart showing the processing flow of the block return means according to the embodiment of the present invention. The block return unit 4 calls the memory corruption check unit 5 and incorporates the block to be returned into the chain of blocks to be allocated.

FIG. 5 is a flowchart showing the processing flow of the memory corruption checking means according to the embodiment of the present invention. Memory corruption check method 5
checks whether the next block physically contiguous with the block to be returned (a block that has not been allocated) is equal to the set pattern, and if it is not equal, it recognizes memory corruption and indicates that the block has been destroyed. Sets the pattern set in the block initialization process in the block and reports the presence or absence of memory corruption.

Next, the operation of the embodiment of the present invention configured as described above will be explained with reference to the drawings.

A job that requires a memory block while executing the program 1 calls the block allocation means 2. As shown in FIG. 2, the block allocation means 2 searches for free blocks and checks whether a block to be allocated exists or not (step 22), and when there is no block to be allocated, performs an initial setting process call process. The initial setting means 3 is called (step 22).

As shown in FIG. 3, the initial setting means 3 performs memory allocation processing to secure new memory (step 31), performs chain creation processing for allocation target blocks to chain allocation target blocks (step 32), and blocks Initial settings are performed to set blocks that are not to be allocated to a specific pattern (step 33), and processing is transferred to the block allocation means 2. The block allocation means 2 performs the empty block allocation process shown in FIG. 2 (step 23). FIG. 6 shows the initialized state of the memory.

A job that no longer needs a memory block calls the block return means 4. The block return means 4 performs a memory corruption check process calling process and calls the memory corruption check means 5 as shown in FIG. 4 (step 41).

The memory corruption check means 5 executes the block corruption check process as shown in FIG. 5, and determines whether the block next to the block to be returned (the block that is not to be allocated) is as shown in FIG. Check whether it is equal to the value set in the block initialization process (step 33).Step 51) If there is memory corruption, perform block correction processing to recognize the memory corruption.Step 52) The pattern set in the block initialization process (step 33) is set in the block, and the presence or absence of memory corruption is reported to the block return means 4 (step 53).

The block return unit 4 incorporates the block to be returned into the chain of blocks to be allocated in the block return process (step 42) shown in FIG. 4, and reports the presence or absence of memory corruption to the calling job.

〔Effect of the invention〕

As explained above, according to the present invention, by arranging blocks to be allocated every other block and checking whether or not blocks that are not to be allocated have been changed when returning blocks, memory is unduly consumed. It has the effect of checking if it has been destroyed.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. FIG. 2 is a flowchart showing the processing flow of the block allocation means according to the embodiment of the present invention. FIG. 3 is a flowchart showing the processing flow of the initial setting means according to the embodiment of the present invention. FIG. 4 is a flowchart showing the processing flow of the block return means according to the embodiment of the present invention. FIG. 5 is a flowchart showing the processing flow of the memory corruption checking means according to the embodiment of the present invention. FIG. 6 is a diagram showing the state of the memory initialized by the initial setting means of the embodiment of the present invention. FIG. 7 is a block diagram showing the overall configuration of the system according to the present invention. 1...Program, 2...Block allocation means, 3.
... Initial setting means, 4... Block return means, 5...
・Memory corruption check means, 6...Memory, 10...
-Control device, 11...terminal, 12...information processing device.

Claims (1)

[Scope of Claims] 1. Information including means for retrieving information held in a memory according to a specification from a work terminal, and means for changing and correcting the information and returning the corrected information to the memory. In the processing system, when the information is returned to the memory, the block allocation means allocates the block according to the chain of blocks to be allocated; Initial setting means for chaining blocks to be allocated in order to allocate them every second; block return means for incorporating blocks to be returned into the chain of blocks to be allocated at the time of return; and means for writing beyond the size of the block to be returned at the time of return. An information processing system comprising: a memory corruption check means for checking whether or not the data has been corrupted.