Abstract: When collecting information about management of a storage of a disk subsystem, loads imposed on a host computer and a network are alleviated to improve the throughput of a computer system having the storage. The disk subsystem includes a CPU and a main memory and information on a disk is collected in response to a request from a management computer. An information collection program is operated on the disk subsystem, whereby, volume management information can be edited on the disk subsystem and utilized by the management computer.

Abstract: According to the present invention, as regards a computer system that uses virtual storage management, because content of auxiliary storage utilized by paging is used, dump information can be obtained by outputting only a part of the content of the auxiliary storage at the time of occurrence of an abnormal system condition. As a result, time required to restart the computer system and business can be shortened. What is more, because it is not necessary to add a special external storage for obtaining dump information, computer resources can be utilized more efficiently.

Abstract: Dump information acquiring and system recovery methods for a computer system using a virtual memory. The computer system has a plurality of external storage units normally used as a paging device unit for holding the contents of the virtual memory to be paged out. When fault occurs, a program for acquiring dump information outputs the contents of the main storage to a dump file. The identifier of the external storage unit set to definition information defining the external storage unit is changed from the identifier of the external storage unit to the identifier of another external storage unit. Thereafter, the computer system is restarted. The contents of the virtual memory held in the paging device unit at the time of fault output to the dump file.

Abstract: In a computer system with a plurality of levels of cache storage, a cache control method prevents data duplication among the levels of cache storage to increase cache storage utilization. A high-level cache staging unit stages reads data from a disk unit, stages the data to a high-level cache, and instructs to destage the data, which has been read, from a low-level cache. A high-level cache destaging unit writes data to be destaged to the disk unit, instructs to stage the data, which has been written, to the low-level cache, and destages the data from the high-level cache. A low-level cache staging unit stages a data, which is written by the high-level cache destaging unit, to the low-level cache. A low-level cache destaging unit destages a data, which is instructed by the high-level cache staging unit, from the low-level cache.

Abstract: When collecting information about management of a storage of a disk subsystem, loads imposed on a host computer and a network are alleviated to improve the throughput of a computer system having the storage. The disk subsystem includes a CPU and a main memory and information on a disk is collected in response to a request from a management computer. An information collection program is operated on the disk subsystem, whereby, volume management information can be edited on the disk subsystem and utilized by the management computer.

Abstract: Dump information acquiring and system recovery methods for a computer system using a virtual memory. The computer system has a plurality of external storage units normally used as a paging device unit for holding the contents of the virtual memory to be paged out. When fault occurs, a program for acquiring dump information outputs the contents of the main storage to a dump file. The identifier of the external storage unit set to definition information defining the external storage unit is changed from the identifier of the external storage unit to the identifier of another external storage unit. Thereafter, the computer system is restarted. The contents of the virtual memory held in the paging device unit at the time of fault output to the dump file.

Abstract: A dump information acquiring method and a system recovery method for a computer system using a virtual memory, the methods being used when fault occurs in the computer system. The computer system has a plurality of external storage units used as a paging device unit for holding the contents of the virtual memory to be paged out from a main memory. During the normal operation, an external storage unit selected from the plurality of external storage units is used as the paging device unit. When fault occurs, a program for acquiring dump information operates to output the contents of the main storage at the time of the fault occurrence to a dump file. The identifier of the external storage unit set to definition information for defining the external storage unit used as the paging device unit is changed from the identifier of the external storage unit used as the page device unit to the identifier of another external storage unit. Thereafter, the computer system is restarted.

Abstract: In a computer system with a plurality of levels of cache storage, a cache control method prevents data duplication among the levels of cache storage to increase cache storage utilization. A high-level cache staging unit stages reads data from a disk unit, stages the data to a high-level cache, and instructs to destage the data, which has been read, from a low-level cache. A high-level cache destaging unit writes data to be destaged to the disk unit, instructs to stage the data, which has been written, to the low-level cache, and destages the data from the high-level cache. A low-level cache staging unit stages a data, which is written by the high-level cache destaging unit, to the low-level cache. A low-level cache destaging unit destages a data, which is instructed by the high-level cache staging unit, from the low-level cache.

Abstract: In this invention, a main storage is divided into an area that should be initialized and an area that should not be initialized at the time when the system is restarted. Part of the main storage area that should not be initialized is allocated to a table for managing a use situation of the main storage and a use situation of an address space. After the restart, for a request for main storage allocation to the virtual space whose contents should be taken over, part of the main storage area that should not be initialized is allocated to a virtual space and part of the main storage area that should not be initialized is also allocated to an address translation table corresponding to the virtual space. For a request for main storage allocation to the virtual space other than the above-mentioned request, part of the main storage area that should be initialized is allocated thereto. At the time of the restart, only areas that should be initialized are subjected to the initialization.

Abstract: According to the present invention, as regards a computer system that uses virtual storage management, because content of auxiliary storage utilized by paging is used, dump information can be obtained by outputting only a part of the content of the auxiliary storage at the time of occurrence of an abnormal system condition. As a result, time required to restart the computer system and business can be shortened. What is more, because it is not necessary to add a special external storage for obtaining dump information, computer resources can be utilized more efficiently.