JPH09330253A - Memory dump method and memory damp system applying the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a memory dump system applying memory dump method with which dump in a state of a fault occurence is enabled without destroying a prefix memory. SOLUTION: This memory dump system has the prefix memory to be used as a CPU personal work area in a real address space and a computer(MCU) 1 to start a memory dump program through a service processor(SVP) 2 when turning an operation system into the state of disabling system down such as fault occurence is provided as a main body. Then, the computer(MCU) 1 is provided with a CPU 3 and a memory(MEM) 4. In the case, the SVP 2 reads the prefix memory from the CPU 3 of the MCU 1 into the real address area of its own memory 4 when starting the memory dump program, automatically stores that prefix memory, saves/preserves it and dumps the prefix memory preserved at the time of memory dump to a magnetic tape 5 or a disk 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a memory dump method for starting a memory dump program when an operating system (OS) in a computer having a prefix memory falls into a state in which the system cannot be down due to a failure or the like, and a memory dump method therefor. Regarding the applied memory dump system.

[0002]

2. Description of the Related Art Conventionally, a computer capable of executing a memory dump has a real address space and a virtual address space, and also has a prefix memory used as a CPU individual work area in the real address space. In the memory dump system including this computer, the memory dump program is started when the operating system falls into a state in which the system cannot be down due to a failure such as a permanent loop or a system up alarm. The most necessary information when analyzing such a failure situation is the program state word (PSW) at the time of interruption, the register (PXR), and the prefix memory. Of these, the prefix memory contains the interrupt routine address, the interrupt source address, and the SV.
The table address of C instruction, basic information of memory management, etc. are stored. In such a prefix memory, failure cause information at the time of system failure is collected by duplicating and storing the system failure information program in the active prefix area and the alternate prefix area.

[0003]

In the case of the memory dump method in the above-mentioned memory dump system, since the prefix memory is not saved before starting the memory dump program, when the cause of the failure is sought from the dump contents, a failure occurs when a failure occurs. Since the prefix memory is not included, and when the memory dump program is started for this reason, some information stored in the prefix memory is destroyed. It has the drawback of disappearing. By the way, since the prefix memory changes significantly during the operation of the memory dump program, if the memory dump program terminates abnormally due to a failure of the output medium, etc. Since the prefix memory of has changed from the state at the time of failure, it does not help the failure analysis.

The present invention has been made to solve such a problem, and its technical problem is to provide a memory dump method capable of dumping in the state at the time of failure without destroying the prefix memory. And to provide a memory dump system to which it is applied.

[0005]

According to the present invention, a memory dump program is started when an operating system in a computer having a prefix memory used as a CPU individual work area in a real address space falls into a state where the system cannot be down. Memory dump method, in which the prefix memory is saved and saved in an unused area of the operating system in the real address space when the memory dump program is started, and the operation system is not used when the memory dump is started. And a dump stage for dumping the prefix memory saved in the area.

On the other hand, according to the present invention, there is a real address space and a virtual address space, and the real address space is C
In a memory dump system including a computer having a prefix memory used as a PU individual work area and having a memory dump program started by a service processor when the operating system falls into a state where the system cannot be down, the service processor is A memory dump system can be obtained in which a prefix memory is read from a CPU of a computer in a real address area of its own memory when a program is started, and automatically stored and saved for saving.

Further, according to the present invention, in the above-mentioned memory dump system, at least one of a storage medium and a recording medium for dumping the prefix memory is included, and the service processor stores the prefix memory saved at the time of the memory dump. A memory dump system for dumping to at least one of a medium and a recording medium is obtained.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION A memory dump method of the present invention and a memory dump system to which the same is applied will be described below in detail with reference to the drawings.

First, the outline of the memory dump method of the present invention will be briefly described. This memory dump method is used when a memory dump program is started when an operating system in a computer having a prefix memory used as a CPU individual work area in a real address space falls into a state where the system cannot be down due to a failure or the like. When the memory dump program starts, the prefix memory is saved in the unused area of the operating system in the real address space, and the prefix memory saving step and the prefix memory saved in the unused area of the operating system when the memory dump is started And a dump stage for dumping.

By going through these steps, even when the memory dump is initially started up or when the memory dump becomes abnormal due to a storage or recording medium failure or the like and is restarted,
Since the prefix memory is saved in another memory, it is possible to dump in the state at the time of failure without destroying the prefix memory.

FIG. 1 is a block diagram showing a basic configuration of a memory dump system according to an embodiment to which such a memory dump method is applied and a flow of operation processing of the memory dump.

This memory dump system has a real address space and a virtual address space, a prefix memory used as a CPU individual work area in the real address space, and a state in which the operation system cannot be brought down due to a failure or the like. The computer (MCU) 1 includes a computer (MCU) 1 whose memory dump program is started by the service processor (SVP) 2 when it falls into the state of (1). Further, here, a disk (DK) 6 as a storage medium for dumping the prefix memory and a magnetic tape (MT) 5 as a recording medium are provided.

The service processor 2 here reads the prefix memory from the CPU 3 of the computer 1 in the real address area of its own memory 4 at the time of starting the memory dump program, automatically stores it and saves it, and saves it at the time of memory dump. The prefix memory is dumped to the magnetic tape 5 or the disk 6.

In the case of the memory dump system having such a configuration, the prefix memory is saved and stored in the memory 4 by the service processor 2 not only when the normal memory dump program is started, but also when the memory dump system is restarted after the abnormal end. Memory 4 acquired at this time
Contains the prefix area at the time of failure.

Regarding this memory dump system, FIG.
The flow of processing at the time of normal execution of the memory dump will be described with reference to the following. In the computer 1, the operating system cannot be brought down due to a failure such as a permanent loop or a system up alarm in the operating system. When the operator has instructed the service processor 2 to stop the execution of the CPU 3 in order to obtain a memory dump when it falls, the service processor 2 performs an operation to stop the CPU 3 via the computer 1 as shown as operation S1. . At this time, if the prefix memory is not stored in the memory area of the service processor 2, the service processor 2 reads the prefix memory from the CPU 3 as shown in operation S2. This is a function for avoiding destroying the prefix memory at the time of failure by reading the prefix memory again when the memory dump becomes abnormal due to an output medium failure or the like and is restarted.

After this, the service processor 2 performs the operation S3.
The read prefix memory is stored at the real addresses X'00000000 'to X'00002000' of the memory 4, as shown in FIG. The area of the memory 4 is directly transferred to the CPU 3 by the function of prefix address conversion when converting a logical address to a real address.
It is an area that cannot be referred to / updated from, and cannot be used by the operating system, so it is always an unused area.

After that, in order to activate the memory dump program, the program status word (PS
W) is set to the top address of the memory dump program, and the CPU 3 is executed. The memory dump program first writes the space in which the prefix at the time of failure is written to the magnetic tape 5 or the disk 6. However, since the area of the memory 4 here cannot be referred from the CPU 3,
Write a channel program as described below, and directly write the contents of the prefix memory saved by the service processor 2 from the channel to the magnetic tape 5 without passing through the CPU 3.
Or write to disk 6.

After dumping the saved prefix memory, the memory 4 always dumps the memory contents directly to the magnetic tape 5 or the disk 6 in accordance with the memory dump program, as indicated by operation S4. When the dump ends normally, the prefix memory saved in the service processor 2 is no longer necessary because the prefix memory is already saved in the magnetic tape 5 or the disk 6. In addition, the memory dump program communicates the normal termination of the dump to the service processor 2 so that the service processor 2 can save the prefix memory again when the next dump is started, and the service processor which has received the communication. After confirming that No. 2 erased the saved prefix memory, the memory dump program ends.

FIG. 2 exemplifies a channel program of the memory (MEM) 4 for writing the prefix memory directly on the magnetic tape (MT) 5 or the disk (DK) 6.

In this channel program, CCW1, C
SEEK is performed by CW2, SEARCH is performed by CCW3 and CCW4, and the block in which the prefix memory is written is designated. xxxx is the SEE position storage real memory address, and yyyy is the SEARCH position storage real memory address. CCW5, CCW6, C
CW7 and CCW8 are real address X'00000000 '
Command for transferring the prefix memory saved from X'00002000 'to the disk (DK) 6.

[0021]

As described above, according to the memory dump method and the memory dump system to which the present invention is applied, the operation system cannot be brought down due to a permanent loop, a system up alarm or the like in the operation system. The memory dump program that is started when a failure occurs The prefix memory is automatically saved to the service processor when the program is started, and the prefix memory saved at the time of memory dump is dumped. It will be possible to refer to and easily identify the cause of failure.

[Brief description of drawings]

FIG. 1 is a block diagram showing a basic configuration of a memory dump system according to an embodiment to which a memory dump method of the present invention is applied and a flow of operation processing of the memory dump.

FIG. 2 illustrates a channel program for directly writing a saved prefix memory in a memory included in the memory dump system shown in FIG. 1 to a magnetic tape or a disk.

[Explanation of symbols]

 1 Computer (MCU) 2 Service Processor (SVP) 3 CPU 4 Memory (MEM) 5 Magnetic Tape (MT) 6 Disk (DK)

Claims (3)

[Claims] 1. A memory dump method for starting a memory dump program when an operating system in a computer having a prefix memory used as a CPU individual work area in a real address space falls into a state where the system cannot be down. A prefix memory saving step of saving the prefix memory in the unused area of the operating system in the real address space when the memory dump program is started,
And a dump step of dumping the prefix memory saved in an unused area of the operation system when the memory dump is started. 2. A service processor having a real address space and a virtual address space, and having a prefix memory used as a CPU individual work area in the real address space, when the operating system falls into a state where the system cannot be down. In the memory dump system including a computer in which the memory dump program is started by the service processor, the service processor automatically reads the prefix memory from the CPU of the computer in the real address area of its own memory when the memory dump program is started. A memory dump system that stores and saves data. 3. The memory dump system according to claim 2, comprising at least one of a storage medium and a recording medium for dumping the prefix memory,
The memory dump system, wherein the service processor dumps the prefix memory saved at the time of memory dump to at least one of the storage medium and the recording medium.